Author Topic: 69 RF brake lock up?  (Read 9429 times)

JKZ27

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Re: 69 RF brake lock up?
« Reply #75 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.
John
69 RS/SS Cortez Silver, L48 MC1
68 RS Ash/Ivy Gold 327EFI M20

jvb6648

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Re: 69 RF brake lock up?
« Reply #76 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. 
Jim
68 Z/28

Charley

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Re: 69 RF brake lock up?
« Reply #77 on: December 19, 2016, 02:59:45 PM »
Also really look at your right front wheel bearings.

Rufcar

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Re: 69 RF brake lock up?
« Reply #78 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

jvb6648

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Re: 69 RF brake lock up?
« Reply #79 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.
Jim
68 Z/28

Kelley W King

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Re: 69 RF brake lock up?
« Reply #80 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.
69 Z28 RS Scuncio Hi Performance
69 SS L78
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BillOhio

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Re: 69 RF brake lock up?
« Reply #81 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
1969 Z28, Burgandy, numbers matching, 12,900 miles
1967 Plymouth GTX Hemi, 4 speed, dana
1961 Chrysler 300G convertible

Kelley W King

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Re: 69 RF brake lock up?
« Reply #82 on: December 19, 2016, 05:48:40 PM »
I would try the pads 1st and then the rotors.
69 Z28 RS Scuncio Hi Performance
69 SS L78
67 SS Chevelle
64 Corvette
66 GTO Tiger Gold
77 Trans Am Special Edition

69Z28-RS

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Re: 69 RF brake lock up?
« Reply #83 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... :)
Gary W / 09C 69Z28-RS, 72 B 720 cowl console rosewood tint
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Rufcar

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Re: 69 RF brake lock up?
« Reply #84 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

jvb6648

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Re: 69 RF brake lock up?
« Reply #85 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
Jim
68 Z/28

Rufcar

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Re: 69 RF brake lock up?
« Reply #86 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

jvb6648

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Re: 69 RF brake lock up?
« Reply #87 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.
Jim
68 Z/28

Rufcar

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Re: 69 RF brake lock up?
« Reply #88 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
« Last Edit: December 20, 2016, 08:14:14 PM by Rufcar »

1969Z27

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Re: 69 RF brake lock up?
« Reply #89 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
Russ 
68 RS L22/M20
69 SS L48/MC1