CRG Discussion Forum

Camaro Research Group Discussion => Maintenance => Topic started by: Rufcar on November 19, 2016, 09:31:13 PM

Title: 69 RF brake lock up?
Post by: Rufcar on November 19, 2016, 09:31:13 PM
Ever since I have this car (3yrs) and have re-restored this car almost entirely the RF disc brake locks up. I 1st removed the additional distribution valve someone added when they installed the new power front discs and that worked somewhat better. I have taken everything apart and if I press more then just a bit the RF locks right up. Any ideas? Tkx
Title: Re: 69 RF brake lock up?
Post by: 1968RSZ28 on November 19, 2016, 11:23:12 PM
Brake hose?

Paul
Title: Re: 69 RF brake lock up?
Post by: 1969Z27 on November 20, 2016, 02:14:52 AM
Should have only one distribution valve.


http://www.camaros.org/brakevalve.shtml
Title: Re: 69 RF brake lock up?
Post by: RAfbody on November 20, 2016, 04:31:04 AM
Brake hose?

Paul

I agree. Check the rubber hose going to the caliper. It could be weak and collapsing not allowing the fluid to return and release the piston(s).
Title: Re: 69 RF brake lock up?
Post by: Rufcar on November 20, 2016, 04:25:47 PM
I did check the hoses 1st and they looked fine as they are stainless and only a couple years old. I did take them apart!
Title: Re: 69 RF brake lock up?
Post by: jvb6648 on November 21, 2016, 12:00:38 AM
What about the LF, blocked line, collapsed hose or frozen caliper. These conditions would send all the fluid to RF.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on November 21, 2016, 04:33:26 AM
Im going to tear into it tomorrow and I will report back Tkx.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on November 28, 2016, 08:25:57 PM
I replaced the front brake hose and bleed the system again and the right wheel still locks up as before?
Title: Re: 69 RF brake lock up?
Post by: Sauron327 on November 28, 2016, 09:22:42 PM
Incorrect intermediate rod length will result in one or both calipers to lock up.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on November 28, 2016, 11:00:28 PM
Tkx Ill ck that next.
Title: Re: 69 RF brake lock up?
Post by: Sauron327 on November 28, 2016, 11:46:29 PM
Just pump the brakes until it locks up, then loosen the MC to booster bolts. If it frees up, therein lies your problem.
Title: Re: 69 RF brake lock up?
Post by: L78 steve on November 29, 2016, 12:49:18 AM
Also try pumping the brakes till it locks up and loosen the bleeder. Any pressure in caliper?
Title: Re: 69 RF brake lock up?
Post by: Rufcar on November 29, 2016, 01:23:50 AM
Don't need to pump brakes locks up as soon as you touch the brakes a bit over a light push.
Title: Re: 69 RF brake lock up?
Post by: Stingr69 on November 29, 2016, 02:37:42 PM
jack up front of car.  apply and release brakes. try to rotate right front wheel and see if it rotates freely.  If not, crack caliper bleeder screw open to release any pressure and try to rotate wheel again.  If it will now rotate freely, you have extra residual pressure in the line going to that caliper.

if it still does not want to rotate freely, your caliper is sticking.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 01, 2016, 08:51:05 PM
I did everything you guys recommended except test pressures and changed out both hoses and bleed. right side locks up. Removed calipers blew out pistons checked for problems and put right side pads on left and left side on right bleed out system, right side still locks up. Right now everything is new except the distribution block and that's coming tomorrow. Hopefully that will solve the problem but I have my doubts! Jim
Title: Re: 69 RF brake lock up?
Post by: JKZ27 on December 02, 2016, 02:10:00 AM
Hey Jim, are you saying the wheel locks up when driving to the point the tire skids or it begins to smoke the pads? Or, does it lock up on jack stands and won't release? Either way, what do you do to get it to release?
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 02, 2016, 07:48:15 PM
While driving, even at 1 mph if you brake more then just a light touch the right wheel will lock up. I have been down shifting for 3 years and then just use an extremely light touch to stop the car.  Anything more than that the right wheel locks up. This afternoon I just received my distribution block. I will try and install tomorrow. If that does not work I'm at a complete loss as its the only part I did not replace.  Jim
Title: Re: 69 RF brake lock up?
Post by: 1969Z27 on December 02, 2016, 09:53:16 PM
Is your mc correct for your car? Does it have the correct piston diameter? MC could be defective? Trash in mc or lines?
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 03, 2016, 05:10:12 PM
MC was brand new last yr and was exactly the same as the one that was on and yes it matches factory. I just now changed out the distribution block and will hopefully bleed today.  Tkx jim
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 03, 2016, 07:41:46 PM
update: Today I changed out the distribution block and bleed the system. Tested car right side still locks up. I switched lines same ting. I ran new lines, Same thing, right side still locks up? The only thing I can see is the right side has a GM  stamped caliper single piston and the left side has no markings , single piston. Maybe the previous owner bought a mismatched set? Im going to but 2 new front calipers, should they be single piston or double? It is the only thing I have not changed. Any ideas or suggestions? Tkx JIm F
Title: Re: 69 RF brake lock up?
Post by: 1968RSZ28 on December 03, 2016, 07:49:12 PM
Im going to but 2 new front calipers, should they be single piston or double?

Jim,

The '69 Camaro came from the factory with single-piston disc brake calipers.  The 4-piston disc brake calipers were used only in '67 and '68.

Paul
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 03, 2016, 08:03:52 PM
That's what I thought too. Im going to order a matched set as its the only thing left. Tkx
Title: Re: 69 RF brake lock up?
Post by: KurtS on December 05, 2016, 01:45:46 AM
Please clarify the issue. It only locks up when applying the brakes, correct? Whenever your foot is off the brake, the wheel spins freely?
So, if the front is jacked up and you pump the brakes, afterwards it spins free? You've confirmed that?

Sounds like the LH front line is plugged in some form from the distribution block to the caliper.
Both fronts are easy to bleed?
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 05, 2016, 03:48:41 AM
Kurt yes to your 1st paragraph. I ran a new temporary line to the LF and the RF still locked up. To be clear it only locks up when driving at any speed when you touch the brake pedal a tad more then very light to slow down. I have replaced everything now except the calipers. I did not think I had too as they were brand new when I bought the car 3 years ago. Yes they always locked up but then continued to get worse over the past 3 years. Upon close inspection it definitely appears the right piston moves faster than the left. Yes I have taken both calipers off cleaned the pistons, applied light air pressure and the both work on the bench correctly I now believe, upon close inspection, they are not identical and that's could be the problem. Tomorrow I will order a new set from "groundup" install them and see if that solves the problem as its the only things left that I can think off.. Jim
Title: Re: 69 RF brake lock up?
Post by: JKZ27 on December 05, 2016, 11:46:27 AM
 Jim,

Is this a factory disc car or a conversion, can you tell?
Make sure it has all the correct and necessary components including the hold off valve and maybe a proportioning valve.
And, make sure it is plumbed correctly, especially if a previous owner did a bunch of work. If you are not sure post some pictures of your set up or reference some photos of original cars. I hate to see anyone replace a bunch of parts when they're not sure what's wrong. Do the rear brakes work at all?
Title: Re: 69 RF brake lock up?
Post by: Sauron327 on December 05, 2016, 12:57:29 PM
Jim,

Is this a factory disc car or a conversion, can you tell?
Make sure it has all the correct and necessary components including the hold off valve and maybe a proportioning valve.
And, make sure it is plumbed correctly, especially if a previous owner did a bunch of work. If you are not sure post some pictures of your set up or reference some photos of original cars. I hate to see anyone replace a bunch of parts when they're not sure what's wrong. Do the rear brakes work at all?

Based on the OP's info, I don't think this is a stock system. In his first post it states an "additional distribution valve" was removed, whatever that was. The factory metering/hold-off valve stops fluid flow to the front brakes until the system sees 30-40 PSI. Without that valve or if it is malfunctioning, the front brakes can lock up prematurely.

I buy GM calipers locally much cheaper than any restoration vendor. They nail you on parts like this.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 05, 2016, 07:58:55 PM
Sauron the old metering valve was removed. The problem from the day I bought the car was under some braking conditions the right front brake would lock up. IN the 3 years of ownership and a full re restoration of the car I bought. It has always done that  and it has done it less without the metering valve. I did not install the disc brakes and there's really no way to know if it came with them from the factory because so many thing have been changed. Tomorrow I get the new calipers and then we will see if that helps. Attached is the set up before I installed another engine last yr. Tkx
Title: Re: 69 RF brake lock up?
Post by: Stingr69 on December 05, 2016, 08:25:56 PM
Crazy idea....right front caliper is hooked up to one of the rear brake cylinder lines and the residual pressure valve is keeping pressure applied.  Trace the lines?  Test - Opening then closing the right front caliper bleeder screw would relieve the pressure in the caliper and the wheel would spin freely again. 
Title: Re: 69 RF brake lock up?
Post by: JKZ27 on December 05, 2016, 08:33:19 PM
Crazy idea....right front caliper is hooked up to one of the rear brake cylinder lines and the residual pressure valve is keeping pressure applied.  Trace the lines?  Test - Opening then closing the right front caliper bleeder screw would relieve the pressure in the caliper and the wheel would spin freely again. 

Sort of what I was getting at. Brake lines look like they're tied in a knot in your photo. Also, I can't tell if that's a 2nd gen combination valve under the master cyl.
Whatever type of system is on there, trace the lines, and make sure they connect where they should.
Title: Re: 69 RF brake lock up?
Post by: Sauron327 on December 05, 2016, 10:21:41 PM
Crazy idea....right front caliper is hooked up to one of the rear brake cylinder lines and the residual pressure valve is keeping pressure applied.  Trace the lines?  Test - Opening then closing the right front caliper bleeder screw would relieve the pressure in the caliper and the wheel would spin freely again. 
Photo is unclear but looks like a combination valve like JK says, which is not original on first gens. Original 67-69 system is here: http://www.camaros.org/brakevalve.shtml The combination valve shown in that link is a later version, original combo valves were cast and more rounded. You said you replaced the distribution block which would indicate it is not a combo valve. Distribution blocks have no valving function per se. Read the link. If it is not a bad or stuck caliper, something is exerting excessive pressure on the system.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 05, 2016, 10:55:55 PM
The new distribution block is exactly the same as the cast one I took out the other day. Interestingly I searched 69 Camaro engine compartment images and in over the 100 I looked at none of them had the metering valve! Yes I know its supposed to be there originally but it made no difference when I had the valve! In fact the front locked up even more! Once I replace the 2 front calipers I will report back.
Yes I did trace all the lines. Jim
Title: Re: 69 RF brake lock up?
Post by: 1969Z27 on December 05, 2016, 11:33:02 PM
Jim. Here's an interesting read on disc converting.


http://www.pozziracing.com/brakes.htm#Converting_Drums_to_Discs
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 06, 2016, 04:44:39 AM
Great info I saved to follow steps. Tkx. Ill let everyone know how I make out. Jim
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 09, 2016, 08:39:38 PM
Today I installed the Calipers and bleed the system right side still locks up with easy braking? That means I have replaced everything the master cyl, the distribution block, the hoses. Ran new temporary front brake lines and the Right side still locks up. $300+ new parts and nothing made any difference. I am at a total loss. Any ideas?  Tkx Jim F
Title: Re: 69 RF brake lock up?
Post by: 69Z28-RS on December 09, 2016, 09:44:44 PM
*Something* is different for certain...

Have you actually replaced *everything* in the brake system..  Except for the rotors?  For completeness I'd measure the thickness of both rotors... and if they are the same thickness, then use some coarse sandpaper and *scuff/sand* both sides of each rotor.   

Do the rotor surfaces, OR the pads have *oil* on either of them??
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 09, 2016, 10:20:06 PM
I microed the rotors and they are exactly the same. I now believe it needs the 1969 disc brake proportioning valve as there is none on this system. I bought this car like this and did not change the set up. So I now believe this set needs that valve, don't you?
Title: Re: 69 RF brake lock up?
Post by: 69Z28-RS on December 09, 2016, 11:40:39 PM
The proportioning valve goes in the line which runs to the rear brakes ONLY..  so I fail to see how that could cause the RF brake to lock up before the LF??   If that was the issue, I'd think the REAR brakes would lock up early...

Note:  I think most of us are responding to your issue and questions as if you have a 'stock' front disk / rear drum system.   A stock system would include the *metering valve* which is installed between the MC front port and the *distribution block*.  Do you have those parts installed in your system, and are the *STOCK*, or are they aftermarket?   I think someone suggested earlier that you might have a 'combination valve' installed RATHER than the distribution block.  The later years combination valves are much different, and if that's what you have in your system, is likely what is causing your problem.   Go read this report... and try to *duplicate* the factory system if you can.
Note:  I have some extra stock '69 Camaro disk/drum parts if you can't find what you need elsewhere.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 09, 2016, 11:47:57 PM
I have been trying to post a pic and its taken me time to resize it so you can see what Im dealing with. Tkx
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 09, 2016, 11:56:38 PM
I have the factory distribution block and the new replacement is exactly the same. I have NO metering valve. There was one on the car originally and it was removed by someone who believed it improved that lock up problem as it was than worse then now. I now believe it was faulty and did not work correctly. I commented incorrectly when I called it the proportioning valve. I believe the metering valve is what I now need. If you agree what exactly can I order as all suppliers are calling that the proportioning valve?
Jim
Title: Re: 69 RF brake lock up?
Post by: 69Z28-RS on December 10, 2016, 04:34:49 AM
If it were my car, I'd find all original 69 parts and rebuild them to factory specs.. and install per the factory...  (I'm old, and prejudiced, but I still believe that the hundreds of engineers utilized by GM did a bit better than the one or two shade tree mechanics employed by most 'aftermarket' suppliers...  :) )

Have you read JohnZ's report on brake valves that I referenced??  it explains the purpose of the 'Metering Valve'.. to delay fluid flow to the front disk brakes until the pressure reaches 30-40 psi to the rear brakes. 
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 10, 2016, 12:52:32 PM
Yes I read Johns article and several more. Like I stated I inherited this problem and trying to make it right. The only item I can see that is not original type equipment is the metering valve. In all the photos, manuals and parts books I have read there are 3 choices, The 71-77 Pro valve the 69 pro valve and the 67-68 valve Some call them Pro. valves others metering. Most appear to use the 68 or 69 valve. I believe since my car was one of the first hundred made in CA. it had the 68 valve, then later was changed to the 69 valve. My car was someone's dragster for many years and thus many changes took place.  FYI Im 67 so I agree with you!
I blew up Johns pic and found the needed valve on line and ordered it complete with bracket and rubber boot. It will be here next week Ill replumb and report back. Tkx Jim
Title: Re: 69 RF brake lock up?
Post by: 69Z28-RS on December 10, 2016, 06:28:59 PM
you posted a photo which did not show a metering valve in place.....  The metering valve would be located with the distribution block under the MC.   A proportioning valve ONLY affects the rear brakes and is mounted on the frame rail in the line running to the rear brakes.

Again, I would suggest you DUPLICATE the factory setup with all factory parts; the proportioning valve seems to be OPTIONAL.   The Metering Valve is NOT optional with the factory setup.

Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 10, 2016, 06:40:19 PM
I found the original metering valve today, cleaned it installed it plumbed it. The right front no longer locks up yea. But now the right rear does.
Title: Re: 69 RF brake lock up?
Post by: 69Z28-RS on December 10, 2016, 06:50:02 PM
The only difference between the Right Rear and the Left Rear ... is the side of the car they are on.  The pressure is the SAME to both..  so address that problem by concentrating on the two rear brakes.. look for 'grease' on the shoes or drums.. clean thoroughly or replace the pads; solve any fluid leaks first.  Check the springs, brake cylinders, etc.. and Adjust both evenly..  Your problem should be gone.. :)
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 10, 2016, 07:10:25 PM
It appears they adjust with the drum off as there is no opening on the rear to adjust?
Title: Re: 69 RF brake lock up?
Post by: 69Z28-RS on December 10, 2016, 07:24:42 PM
If it's a factory backing plate, there will be an opening, but it may have a dust seal pressed into place...  The hole should be directly behind the adjuster wheel.  look for the rubber plug and remove it...
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 10, 2016, 09:56:22 PM
Ok up date! Rear Right cyl. leaking. Replaced and cleaned. Brake shoes adjust internally there is NO seal, probably because its a 70 or 71 Nova rear! Who knew? I ran the serial number on the axel. Cleaned both sides. Adjusted by putting drum on and off using adjuster. Car stops perfectly now! YEA! Tkx for all your advice.

For the record here is my 400hp camaro
Title: Re: 69 RF brake lock up?
Post by: JKZ27 on December 10, 2016, 10:44:00 PM
Fixed!!!  :D
Good for you!
Title: Re: 69 RF brake lock up?
Post by: Sauron327 on December 10, 2016, 11:09:05 PM
I can only assume since one wheel cylinder was leaking the other is tired, as well as the rear flex line. if that collapses, your rears will lock up again.

Paint your grille surround orange the way it is supposed to be originally. If you so desire of course.

Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 10, 2016, 11:25:46 PM
Sauron327 Tkx the other cyl is new. Not much stock on this car in many years. That's why I bought and built it the way I wanted, though I did use all GM parts that were available in 69. I built one similar in 1970 with same side exhaust. If it was original id keep it that way. Tkx
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 11, 2016, 02:39:54 PM
Here is the pic of the old metering valve and new plumbing. Tkx again for all the advice and what makes this forum great!  Merry xmas. Now off to finish up my 70 Chevelle project! Jim F
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 12, 2016, 09:47:27 PM
Took her out today around the property and it seems the RF is locking up again except I need to brake harder to do that. I think it may be the old metering valve I installed. I did clean it up and blow it out and it seems to work with 35lbs of air pressure. Your thoughts?
Title: Re: 69 RF brake lock up?
Post by: z28z11 on December 13, 2016, 02:20:39 PM
Look up the thread(s) on the site for the metering valve rebuild protocol. You can order the kit and rebuild it yourself, pretty simple and inexpensive procedure. Both proportioning and metering units should be up to snuff - you can do both -

Regards,
Steve
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 13, 2016, 03:37:02 PM
Tkx steve will do. Jim
Title: Re: 69 RF brake lock up?
Post by: 1969Z27 on December 13, 2016, 11:58:17 PM
Seems like you're unsure which wheel is locking up? I'd get a helper to watch from outside of car to verify which wheel is locking.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 14, 2016, 03:16:10 AM
I did it's def. Rf. Again.
Title: Re: 69 RF brake lock up?
Post by: 1969Z27 on December 16, 2016, 12:28:15 AM
Hi Jim. In post #50. Is that some kind of adapter in master cylinder that the front line is screwed into?
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 16, 2016, 12:44:46 AM
Nope it's mstr cyl to metering valve. Then rear of metering valve to distribution block as per pic in crg factory pic.
Title: Re: 69 RF brake lock up?
Post by: Sauron327 on December 16, 2016, 02:06:57 AM
Hi Jim. In post #50. Is that some kind of adapter in master cylinder that the front line is screwed into?
To me it looks like adapters used with incorrect lines. I've used them before in other applications when using universal brake lines. Complete adapter lines are also now available for repairs. Since all the correct pre-bent factory lines are available for these cars, there is no need for adapters. They don't affect the braking, they just do not look original.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 16, 2016, 03:02:25 AM
Sauron, I agree. It,was all I had as I just wanted to see if the system worked.  Hopefully tomorrow my new meter valve Will be,here as I was not able to cancel the order.
Title: Re: 69 RF brake lock up?
Post by: Sauron327 on December 16, 2016, 03:11:24 AM
Sauron, I agree. It,was all I had as I just wanted to see if the system worked.  Hopefully tomorrow my new meter valve Will be,here as I was not able to cancel the order.
No worries. One of my cars has adapters. Not every car needs to be a non-driving trailer queen.

How did you verify the intermediate rod length and clevis rod adjustment?
Title: Re: 69 RF brake lock up?
Post by: Kelley W King on December 16, 2016, 03:09:47 PM
I think I would look to see if the right and left have some differences. Maybe the calipers do not have the same clearance? Maybe the pads are not the same thickness? Maybe the rotors are not the same thickness? If all else fails swap the pads left to right, and maybe the rotors. But I would do one thing at the time so if it fixes it you will know for sure what is was. My corvette with drums did it only when cold and it turned out to be one auto adjuster was working and the other was not.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 16, 2016, 04:52:05 PM
Kelly in earlier posts I list that I changed everything and checked the rotors. The metering valve was missing and I install an old one. That's why I am installing a new one today.
Title: Re: 69 RF brake lock up?
Post by: 69Z28-RS on December 16, 2016, 05:08:00 PM
Kelly in earlier posts I list that I changed everything and checked the rotors. The metering valve was missing and I install an old one. That's why I am installing a new one today.

Where did you find a NEW (original) metering block??
Did you ever verify your distribution block was a GM original part, and disassemble/clean it??
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 16, 2016, 06:32:05 PM
I removed the distribution block when I installed the exact repo and blew it out and it seemed fine but I install the new one. I will know more once I bleed the system with the the new rebuilt metering valve.
Title: Re: 69 RF brake lock up?
Post by: Dave Siltman on December 17, 2016, 03:44:49 PM
Maybe it's me, and I'm probably older than a lot of the young whippersnappers here, but here are my thoughts: Rufcar, you have a fair amount of money invested in a '69 Camaro that is sure to appreciate in value. PROTECT yourself and your investment! That bunch of mangled brake lines looks like a day-old bowl of spaghetti! Instead of chasing the rabbit that you apparently can't catch, buy a kit from Inline Tube, Ground Up, or the Right Stuff and stop aggravating yourself! The kits, while technically not 100% concours correct, appear relatively like original (get the correct kit with the '69 hold-off valve) and WILL STOP YOUR CAR without you WHITEKNUCKLING THE STEERING WHEEL!!! As another member posted earlier, and I agree,  GM spent tons of money and employed many engineers perfecting that disc front/drum rear system. If it worked in 1969, you can make it work in 2016 by simply replicating the system! I get that you wanna save money, but skimping on brakes isn't the place to do it! What happens if you are out exercising those 400 ponies and a kid jumps out in front of you, or somebody texting in the intersection up ahead doesn't see the light change? I may have some used-but-still-usable parts in my stash, but when it comes to safety my friend, I blueprint every item in the steering and braking all of my cars. Good luck, Sir!!!
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 17, 2016, 05:31:07 PM
http://www.camaros.org/images/brvalve/bv_mcylpipes.jpg
 This is the picture you guys gave me in the earlier posts and I copied it. What didn't I do that is not exactly like this pic other then those 2 reducing fittings on the MC? Remember I inherited this problem when I purchased the car and have changed out everything to match that factory pic. I was doing Rolls and Bentley restorations many years before I started to again do muscle cars and RR has over 90,000 parts per car and extremely complicated brake systems. Yes Im over 67 years old too! Yes I have way over 40K in this car without my labor and I am never trying to save money always trying to do it right and I thought I was as I have followed everyone on here's advice. Once I get to bleeding the new parts I will report back.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 17, 2016, 06:39:03 PM
Today bleed system with new metering valve and right wheel locks up 1st! All front parts are new and so are both rear cylrs. I have done everything to spec and I have gained nothing. I thought I had it after I Installed the 40 yr old metering valve but the rear cyl went out, repaired those and then the RF  front locked up again. Got a new metering valve and now Im back to the beginning where RF locks up on easy braking. I am now at a loss as I have everything to the factory picture and parts. 
Title: Re: 69 RF brake lock up?
Post by: 69Z28-RS on December 17, 2016, 10:13:42 PM
Sometimes it helps to have a new pair of eyes looking at the problem, especially when it gets to be as frustrating as this must be for you.  Do you have any closeby automotive friends you could ask to come over and help you assess the problem?  ie..  Just step back and think at a high level about what all you've done??
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 17, 2016, 11:03:38 PM
I actually have had 2 stop by 1 was a gm mechanic for a dealer for over 40 years the other works on mainly Jap cars and both are stumped. I may change out all the front steel lines and see if that helps. Today I re read all the articles on 1st gen brakes to see if I missed anything. I looked up Ground up 396 Mstr Cyl and Vac booster kits and they are plumbed differently then the picture on the CRG brake page as they have the Metering valve line to the  LF side of the dist. block instead of the front center!  I have mine plumbed exactly like the CRG pic. I have been stumped on complicated things before and I am sure I will resolve this. Even though I am replacing a bunch of newer parts all will be evenly new when Im done replacing the rest. The car is in one of my heated garages for the winter so I have all the time to find the problem.
It really is sort of simple and that is, something is giving me more pressure to the right front wheel or less pressure to the LF wheel. Humm now I wonder what that is, then problem solved!
Title: Re: 69 RF brake lock up?
Post by: 69Z28-RS on December 17, 2016, 11:14:46 PM
If you are using ANY aftermarket parts, then all bets may be off re what we suggest to you here regarding the original system.  The Distribution block in the 69 Camaros was ONLY a distribution block, whereas over the years since then, mfg have gone to a 'combination' valve, which actually does various valving functions as well... Mixing systems of two different designs could be causing what you are experiencing...
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 17, 2016, 11:23:09 PM
I appreciate that and I will continue to search out the cause. Tkx for all your help. Jim
Title: Re: 69 RF brake lock up?
Post by: Dave Siltman on December 18, 2016, 01:52:38 AM
My guess is that there is a kink in one of the steel lines. In one of the latest posts, you said something about replacing the front steel lines; are you now telling us that the current front lines are old? Have you examined all of them CLOSELY and looked for any kinks? If a previous owner installed headers, there is a good chance one or more of those lines were bent, either intentionally or unintentionally. Many headers make contact with brake lines or junction blocks making an "adjustment" necessary. Shadetree mechanics are not fun to follow!
Please keep us posted on all updates or discoveries.
Title: Re: 69 RF brake lock up?
Post by: 67 RS Ragtop on December 18, 2016, 03:14:11 AM
Just wondering (maybe I missed it) what was the hydraulic pressures at both front calipers, while under light application? In my past life I used a set of gauges and actually verified pressures right to left, or front to back, etc., on problem vehicles (formerly a Factory rep for a truck manufacturer). This may be be a way to confirm the "cause" of your ongoing issue.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 18, 2016, 04:28:16 AM
Dave I did not replace the front lines but I did run a new temporary line to the left front wheel and the right still locked up. A bent line to the right should make the left front lock up yes?
67 RS I was thinking the same thing today. I just have to make a gauge up as I did check all out local suppliers and they have none. Any suggestions on a gauge I can use and plumb in? I am also not sure of total pressures. I read the list on our site here and some pressure go over 1000 psi under braking?  I also did not see any specific gauges on line for sale only ones used in an ABS application.
Title: Re: 69 RF brake lock up?
Post by: JKZ27 on December 18, 2016, 02:51:39 PM
http://shop.advanceautoparts.com/p/otc-brake-pressure-test-kit-otc7488a/17632264-P

This should work for testing hydraulic pressures, ABS or not. Try to find one to rent.
Title: Re: 69 RF brake lock up?
Post by: jvb6648 on December 19, 2016, 04:36:48 AM
You plumbed your lines from a picture, the inlet port should be next to the switch, if the inlet port orifice is larger and that port now goes to the  RF you are sending more fluid that caliper. Check the 3 orifice sizes with a drill bit. If one is larger that's the inlet. Set it up as the assy manual. 
Title: Re: 69 RF brake lock up?
Post by: Charley on December 19, 2016, 02:59:45 PM
Also really look at your right front wheel bearings.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 19, 2016, 03:17:28 PM
Jim It is plumbed exactly as the assembly manual and the picture on the CRG brake restoration page. Charley, I will recheck those bearing but they only have 6K mi on them and there's zero play in the wheel.
I ordered a brake pressure test gauge kit as none of the 3 auto parts suppliers near by had or could get them? Who knew as there on line info says they have them! Im in no hurry I have all winter. I am going to swap out the rotors and see if that helps at all. Tkx. Jim
Title: Re: 69 RF brake lock up?
Post by: jvb6648 on December 19, 2016, 03:55:10 PM
Ok, mines a 68, maybe they changed in 69. Still those orifices are probably the only thing you haven't checked, if they are different sizes and aren't in the correct port it may be your problem. The caption next to the photo of the distribution valve says it's showing the inlet port. You must have pulled out most of your hair by now but hang in there, everyone who has posted here want to see this issue resolved as much as you do.
Title: Re: 69 RF brake lock up?
Post by: Kelley W King on December 19, 2016, 04:52:17 PM
I would still swap parts from left to right. No cost just time. I think it time to eliminate parts that are not you problem. Something else is make the right caliper is letting the pads retrack when releaseing the pedal.
Title: Re: 69 RF brake lock up?
Post by: BillOhio on December 19, 2016, 05:29:29 PM
If he swaps calipers side to side the bleeders will be down and all kids of issues arise
Title: Re: 69 RF brake lock up?
Post by: Kelley W King on December 19, 2016, 05:48:40 PM
I would try the pads 1st and then the rotors.
Title: Re: 69 RF brake lock up?
Post by: 69Z28-RS on December 19, 2016, 06:01:01 PM
Rather than buy new rotors, or pads, that you might not need, I'd suggest giving both a good 'sanding' with a coarse (80 grit) paper and flat block, cross hatching appropriately to see it you have an issue with glazing of pads/rotors.   Someone suggested making sure your bearings are good first, which is also a good step... to make sure the rotors spin free, smoooth, and easy... :)
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 19, 2016, 06:20:28 PM
Listen I love you guys and all your advice
but before posting you really should read the previous posts! I have swap'd sides. I have replaced pads, calipers, lines, master cly, distribution block metering valve and flex hoses.
After replacing everything and thinking on this it cant be the metering valve because the system will work properly without it. Its only needed on slippery roads. It cant be the distribution block as all 3 orifices in the front are the same (unless blocked) It cant be a blocked left line pushing more to the right because I ran a new left line and it didn't help. Its not the rear any more since I replaced those cylnds. The only thing that actually makes the pressure work is the master cyl. It is possible the rod is not working properly and effecting the way it moves over both the outlet holes. I may purchase a new entire unit as my booster is older then the rest and that way I can have an entirely new system. I don't care if I now have a lot of good used parts as I can sell them or use them on my Chevelle project. Today a friend of mine who is a retired GM mechanic of 40+ years looked at the project and thought the same thing. In face no matter how you plumb the 3 front holes in the distribution block it will still work with 1 in and 2 out evenly as again all openings are the exact same. The repo set has it plumbed differently then the factory and it works! I will get this it is challenging and interesting too. Jim
Title: Re: 69 RF brake lock up?
Post by: jvb6648 on December 20, 2016, 02:09:18 AM
Jim,
Bear with me on this. I have a 68 with disc/drum, I didn't post without first examining my distribution valve. Let me preface this by saying that I am a retired heavy equipment mechanic and know enough about hydraulics to be really dangerous. Gauging the orifices I found that my inlet is 1 drill size larger than the outlets. If you buy a mc booster and valve assembly the inlet to the distribution valve will be next to the switch and it is for 67 to 69. This is the inlet for a reason. The only thing common to the both front brakes is the distribution valve. The only thing that will affect the front brake operation is the fluid entering that valve, nothing else upstream matters to the front brake operation. All your components are new. Now I ask you to double check the AIM and the plumbing, at this point it can't hurt to reconfigure, you've tried everything else. Again the inlet port, even if the 3 orifices are the same, try it, you have nothing to loose but more brake fluid. You must have used 5 gallons by now. If I'm not sure about something I'll back off but if I think I'm right I can be like a junk yard dog. I really believe that if you buy a new mc booster valve set up and reconfigure the tubing to what you have now that nothing will change. I'll bet you a dinner on that. You can try this too if you like. Take one of your other distribution valves and drill the orifice to the LF one size larger. That will cause a restriction to the RF. I'm going to bow out now that I've put in my 2 cents worth, maybe a nickel. Jim maybe take a break and enjoy the holidays and get back to it next year.
You asked for help, Be careful what you wish for. All the best, Merry Christmas, Jim
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 20, 2016, 04:03:10 AM
Jim its worth a try and there is no such thing as too much advice only not enough. I will try that plumbing arrangement my only question is why are all the original systems plumbed like mine and only the replacements plumbed differently as they all use the same distribution block? Tkx Jim
Title: Re: 69 RF brake lock up?
Post by: jvb6648 on December 20, 2016, 05:01:18 AM
I don't know Jim. I went by the drawings in my 68 AIM and if the 67,8 & 9 were the same system I felt the same drawing would apply to your car. I was going to post the drawing but I couldn't down size it. I could PM it to if you want. I don't know why they would have changed the plumbing either. If enough stuff gets thrown at the wall hopefully something will stick.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 20, 2016, 06:19:51 PM
Jim I re plumbed the system today as per all new sets ups (yes I used bushing to test) The right wheel still locks up under light braking! Pic attached.
I  also checked the original Dist. block and the right side hole is exactly one drill size larger than the center and right side holes! But still locks up. I need to rethink your suggestion on drilling the  Left wheel hole larger so the RF wont lock up. Humm That should allow more fluid to go to the left wheel and allow less fluid to the right thus helping that wheel not lock up! That does make sense so that will be tomorrows project. Tkx Jim F
Title: Re: 69 RF brake lock up?
Post by: 1969Z27 on December 20, 2016, 11:18:09 PM
Jim
Not sure how you verified booster to master cylinder pushrod length? Appears there are two different lengths and two different master cylinders with different depth pockets. The longer pushrod used with the shorter depth pocket mc will not allow piston to fully return to its stop.


http://www.camaros.net/forums/16-brakes-suspension-steering/158228-master-cylinder-push-rod-length.html
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 21, 2016, 12:08:09 AM
That is a possibility.  Someone suggested I losses the MC a bit and see if that helps. I did that didn't help.
Title: Re: 69 RF brake lock up?
Post by: jvb6648 on December 21, 2016, 02:30:42 AM
You lost me. You mentioned the right side twice. If the large orifice was the inlet and it still locks up then I'm back to square one. Use one of the old blocks and if you can set it up as the 69s are go for it. My only concern is that you treated the symptom and not the disease.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 21, 2016, 02:41:22 AM
I'll elaborate,  the block has 3 holes which I cked.one large 2 smaller It came to me with one small to one side  one small to supply one large to rightwheel, though I didn't know that until today.  I re plumbed it one large to supply 2 small hole each to one wheel. Still locked up rf wheel.
I'm looking into an in line reducing type valve.
Title: Re: 69 RF brake lock up?
Post by: Dave Siltman on December 21, 2016, 11:35:07 AM
Is that last picture your car.....I'm so confused! If so, why all the fittings at the end of the lines where they connect to the valve? And, is the m/c new? Old? Rebuilt/refurbished? There is a missing link here and/or an old part that hasn't been addressed. In my mind, there is no reason this can't be rectified by duplicating the factory set-up. What in this system isn't new???
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 21, 2016, 12:56:55 PM
Dave in earlier post I explained every detail with current pic and factory pics I have replaced everything except the booster and the 2 main twisted supply lines. I blew those out I even ran temporary line to both to test. I explained in the previous post those reducers were temporary just to test. I changed the plumbing 3 times I did use factory specs I rebuilt the rears too because 1 leaked. The car always stops and the RF always locks up 1st and then releases. Nothing has changed in 3 years and 6k mi and this is the 2nd time Im doing everything. I have had several 40yr experience mechanics stop at my shop and advice from many on line and nothing works. I try something new every few days I even tried a different distb. block with larger holes to the RF. Im at a total loss.
Title: Re: 69 RF brake lock up?
Post by: Dave Siltman on December 21, 2016, 03:12:53 PM
Does the r/f lock up with no weight on it? If the car is off the ground will the problem occur? I'm wondering if the issue isn't brake related but suspension. Earlier in the thread, Charley made mention of a wheel bearing and nobody really followed up on it. I'm asking about the lock-up or "dart" while driving because if it doesn't occur in a static state, possibly the r/f steering and/or suspension pieces could have irregularities. I'm also wondering if the subframe is "tweaked" with a difference in wheelbase from the left side. If the lock-up does occur while on stands or a lift, then this theory would all but be overruled.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 21, 2016, 04:04:22 PM
Dave I spun the wheels on my lift and rf still locks up. Thus a.m I re plumbed yet again and ran the left front to the largest hole and rf to the smallest hole in the distb.block and it rf still locks up. FYI my garage is 100 ft long. I back off the lift to the door drive aprox. 59 ft and just push on the brakes to stop as normal rf always locks up and releases once foot is lifted a bit. I have now plumbed to every combination,  replaced everything except booster and hard lines to wheels. Nothing helps. I may need to order a complete booster mc kit and start over. I also may try an line reducer valve.
Title: Re: 69 RF brake lock up?
Post by: 69Z28-RS on December 21, 2016, 04:10:02 PM
Personally, I think you have a 'combination valve' installed rather than a 'stock distribution block'... they appear to be alike on the outside I believe, but several have commented that the 'new one' you installed appears to be aftermarket (and I agree).   Where did you purchase that part?  I'm unaware of any seller of the original distribution blocks...  ?
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 21, 2016, 04:57:41 PM
I bought it from Groundup 396. I checked both the old original and new replacement and both are cast and the only differences I can see are all 3 front end holes are all 1 drill size larger then the original . That also is 1 large and 2 small holes. The one to the left of the brake switch is the larger in both cases and the front center and engine side are both small. I have plumbed both all 3 possible ways and made no difference.
Title: Re: 69 RF brake lock up?
Post by: 1969Z27 on December 23, 2016, 12:35:20 AM
Jim,
 Have you checked the bake pedal pushrod clearance? There should be a little brake pedal movement before pushrod engages booster. Also have you checked which hole is pedal pushrod in? Pushrod should be attached to the lower hole for power assist brakes.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 23, 2016, 01:47:14 AM
Yes that was one of the 1st things I ckd its,all to spec.
Title: Re: 69 RF brake lock up?
Post by: Charley on December 23, 2016, 02:03:41 AM
I would be looking outside the box for something goofy that you would not think could have a effect. Ball joints, worn spindle, etc.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 23, 2016, 07:24:35 PM
Charley I am. Tkx Jim
Title: Re: 69 RF brake lock up?
Post by: Mike S on December 23, 2016, 07:42:37 PM
 I've been following this thread with interest. This is more interesting than watching the presidential elections.  ;)
Question: When you checked on the lift to see when it locks up, are the rear wheel brakes engaged too whereby the drums are locked? I'm wondering if maybe it is the left front brake not grabbing the rotor making it appear the right front is locking.

Just a thought (and grasping at straws!)

Mike
Title: Re: 69 RF brake lock up?
Post by: Dave Siltman on December 23, 2016, 08:53:17 PM
I initially thought the same thing.....what if the left front brake isn't working making it FEEL like the right one was overworking, but I think we're past that.
Title: Re: 69 RF brake lock up?
Post by: jvb6648 on December 23, 2016, 09:07:27 PM
Jim, Do you have access to a couple of scales, maybe a highway patrol or trooper friend who works truck inspections. You mentioned that this was a drag car for a while. If the body is twisted it could make the R/F light and make less work for that brake causing the lock up.
Jim
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 23, 2016, 11:24:01 PM
With just about everything replaced Im taking time to re
think what my next step is. I will let everyone know how I make out in the up coming weeks. Happy holidays to all!
Title: Re: 69 RF brake lock up?
Post by: Dave Siltman on December 27, 2016, 01:14:17 AM
Did you ever measure the wheelbase from side to side? Back in the '80s we "staggered" the front wheels in my Chevelle drag car to get about an inch and a half more rollout in the starting beams. If you slammed the brakes and weren't ready for it, the car would dart to the right because that front wheel was set back farther than the left. I'd try measuring the centerline from side to side and then get the car in the air and get it "squared". If for nothing else, it might eliminate something else from the equation.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on December 27, 2016, 08:24:33 PM
Dave I didn't actually measure the front but I have set up on a 4 wheel alignment machine. It was a dag car years ago but I figured the 4 wheel adj would catch that? 
After I wrote that paragraph I took the old girl out for a drive and after my last plumbing which was to put the left wheel into the larger hole of the distribution block on fender side and the RF to the engine side and smaller hole and the MC to the front center hole the car was much better. I drove on back roads and braked a lot and as long as I didn't HIT the brakes but only pushed on them the car was fine. Though even at slow speeds, like approaching a light if I pushed a bit harder it would lock up and release. The way it is now seems to work better then it ever did though not perfect. Since it is a 4 speed with huge torque and compression the car always slowed easily. I can def live with it like this or until I find the answer. Tkx Guys! Jim
Title: Re: 69 RF brake lock up?
Post by: 1969Z27 on January 29, 2017, 05:19:50 PM
Hi Jim. Have you made any progress? I was having similar problem with my 1997 GMC truck and thought I'd share how I fixed it.
One rear wheel cylinder was leaking. So I replaced both. Brakes worked fine until the humidity got really high or during rainy spells.
That's when barely touching the pedal right rear would lock up. After the humidity and storms passed it would go back to working fine.
I thought it might have something to do with the brake fluid that had been absorbed into the brake shoe. I switched the shoes from one side
to other side. Sure enough during the next rain the left rear would lock up barely touching the pedal. Replaced both sides with new shoes.
Haven't had any issues since.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on February 04, 2017, 03:37:46 PM
69z27, I did have a rear leak in new cylinders and changed that one re adjusted both right front still locks up. I sort of gave up as I changed everything and it made no difference.  I have been driving it that way now for close to 5k mi. I know how to stop without locking by just slowing down gently. 
Title: Re: 69 RF brake lock up?
Post by: myblue67 on July 12, 2017, 12:24:41 AM
Did you reach any conclusions? Similar problem. A new master cylinder fixed the problem for about three months...now returned. Hard to believe it is a MC again.
Title: Re: 69 RF brake lock up?
Post by: Rufcar on November 01, 2017, 06:24:22 PM
Sorry I have not been on all summer. I was completing my 70 Chevelle full restoration, also did a 71 Rolls coupe and just now finished a 89 Jeep YJ. I drove the Camaro approx. 1000 mi this summer with the brake problem. I have replaced and tested every brake component and in the end nothing helped! RF still locks up under light pressure. I even gave the car to another 40 yr experienced mechanic who swapped and tested everything and accomplished nothing. Spoke to several experienced muscle car specialist around the US and to date its still exactly the same. So for now It will stay like it is as I can drive around it and have for 4 years now. Over the winter I may go it once again. Tkx Jim F