Where to by correct master cylinder?

[DAVEN1256]

I want to buy a new master cylinder for my '68. I have power front disc brakes. My original master cylinder is long gone. I would like to have one with the correct casting number and definitely the double bleeder valves on it.

The correct casting number for my car would be 5460364. I have looked at online at every company I know to look at and the only one is see who has that is HBC for $195. There are several companies that offer one with the casting number 5468309 which is correct for '69.....with prices ranging from $60 to $104.

First off, I can't see my way clear to pay almost $200 for a master cylinder so three questions.

Does anyone know of a cheaper source for a 5460346 master cylinder?

If I go for the cheaper incorrect 5468309, is there a difference in quality between suppliers. I don't know if there are many different manufacturers or if maybe every supplier gets theirs from the same one.

Are there noticeable physical differences between the 5460346 and 5468309?

Thanks.....Dave

[ko-lek-tor]

Advance Autoparts and maybe others (national chains), have rebuilt ones for $20-25. I'll check the one I have again just to be sure. It's laying on the floor over in the corner of the shop. Pretty sure it had the casting you want. I took the guts out of it to rebuild my 309.

[Stingr69]

Many "rebuilt" master cylinders these days will be newer service replacements without bleeder screws.  Still worth a look.

If you buy a correctly dated and cast number core and restore it you might save a little money but not a bunch. They need to be sleeved and have new parts installed.  Some internal parts do not come in the kit and are not available anywhere else, and you will need those so....

Compare finding and buying a correct casting number, date coded core then having it sleeved.  Add the cost for buying a non-correct "rebuilt" unit at the parts store and scavenging the internals to use in your re-sleeved core.  Maybe doing it yourself is not so cheap in the end?


My take on it - if you still have the correct core - do it yourself.  If not, it will be expensive no matter which way you go.

-Mark.

[cook_dw]

Ahhh those were the days..  Back 15-20 years ago when I was finishing high school and through college I worked at auto parts stores and when I would hit a new store or town I had a list of part numbers I would pull from their inventory and look them over..  I got lucky more than once on masters and water pumps but never could score on distributors..  Helped get extra cash when going to swap meets..   

This is one of the last of my stash that I kept for backups..  And no it isnt for sale..

[DAVEN1256]

Thanks for all the replies so far.

Advance Autoparts and maybe others (national chains), have rebuilt ones for $20-25.

Are you saying you can find master cylinders with correct casting numbers and double bleeders at the auto parts stores? I have heard of people finding parts like that at those stores but only buy chance.

I would like to get something out of the box that is ready to go rather than fixing a used core but I'll definitely consider that.

Having the correct casting number would be nice but it is not an absolute necessity......I do however, definitely want to have the correct original shape with the double bleeder valves. .........So then I ask myself, is it better to have the wrong casting number (the 5468309 for '69) or one with no casting number at all. Right Stuff, NPD, and D&R Classic all offer the correct shape with the bleeders and no casting number. I guess it's just up to me to make up my mind on that.

Going back to one of my original questions, no matter who you buy a new one from, is the quality about the same? I don't know if there are a lot of manufacturers out there or if most of the parts houses get them from the same place.

Of all the new master cylinders I have looked at online, none of them say anything about already being stainless steel sleeved. I would assume that are not. Can anyone comment on that?

Thanks.....Dave

[ko-lek-tor]

Ok. My memory was not as good as I thought. There are no bleeders. The cap alone is worth buying this part,IMO.

[bertfam]

There were lots of applications for the 5460346 master cylinder. not just the Camaro. Among them was the 68-74 Corvette, with the only difference in this case being no RPV (residual pressure valve) installed in the Corvette (4 wheel disc brakes instead of rear drums, so no RPV required).

Places like Paragon and CORVETTE CENTRAL sell the 5460346 casting master cylinder for the Corvette for around $130, so that might be an option for you. You WOULD have to add the RPV to the master cylinder though (and of course the "WT" stamp).

Paragon only sells it with the Corvette "PG" stamp, but Corvette Central sells it with or without the stamp (my above link is for the one without the stamp).

Since it's the same casting number, you would think some smart cookie would start making the 67/68 Camaro application, but NOOOOOOOO!!

Ed

[DAVEN1256]

The RPV you speak of, are you referring to the external hold off valve separate from the master cylinder or something inside of the master cylinder itself?

Dave

[bertfam]

No, the RPV is in the master cylinder. HERE'S THE CRG REPORT showing the RPV and the explanation.

Ed

[DAVEN1256]

I had no idea about the RPV internal valve. I learned something today.

So a 5460346 casting master cylinder for a Corvette is not correct for a Camaro because the RPV for the rear brakes would not be there.

What is involved in putting one of these valves into a Corvette master cylinder to make it suitable for use in a Camaro. I seems like more of a project than I would want to get into but maybe not.

Dave

[69Z28-RS]

I went to ebay looking for a RPV for a Delco MC, but only found a bunch of aftermarket RPV's.   Interestingly, they have RPV wtih 10 psi residual pressure for disk brakes, and with 2 psi residual pressure for drum brakes.  Looking at this, it seems the 'spring' shown in the CRG brake report basically 'goes with' the RPV?  ie..  if no rpv, then is the spring necessary??  Is there a source for the stock Delco RPV if you needed to add one to a MC without them?

[bertfam]

I don't know of any GM part number SPECIFICALLY stating "Residual Pressure Valve", so it may not have been able to have been ordered separately. You can see from the exploded diagram below that the RPV isn't even shown! However, there's a "Repair Unit" (Group 4.649) for the Camaro as P/N 5462708 (1967 with disc brakes) or P/N 5468449 (1968 with disc brakes), but it doesn't say what's included in the kit!

There are two "Valve assemblies" listed in the P&A. The first is under Group 4.657 and it's P/N 5462642, ("VALVE ASSY, MAIN CYLINDER CHECK"), and it's used on ALL 67-69 cars ("as required"). The second is under Group 4.658 and it's P/N 5462684, ("VALVE ASSY, POWER BRAKE CYLINDER"), and it's used on the 67-68 Camaro and the 68-69 Nova. But again, no REAL description what either these valves are for! If I were to guess, I'd say the RPV is probably P/N 5462642, but that's just a WAG.

Napa might be able to get the RPV, but to be honest, I've never researched this very much.

Ed

[69Z28-RS]

I never have either, Ed.  It was curiousity that pushed me to check ebay and then make the post...  I have a couple of extra Chevy/Corvette Delco MC's (509/DC and 309/US) that I probably should sell, but wouldn't want to misrepresent...

(Anytime I realize I'm totally ignorant on a subject, I like to try to 'fill in some of the hole'...

[JKZ27]

The check valves appear to be included in NAPA's master cyl kit  UP501 or UP472, FWIW.

[TRLAND]

I could not find the RPVs either when I needed them in a replacement MC a few years back.  I had to buy one of the NAPA MC rebuild kits that John mentions above. So ~$30 for 2 little rubber valves(!) but I also used the brass ports from the kit too even though I didn't damage the old ones when I removed them.

Dave: They are not hard to install. Pull the brass port out by threading a drywall screw into the port and pulling straight out using a claw hammer.  You can get fancy and use a finer thread screw and some washers as a puller so as not to damage the brass port but if you do the ones from the kit can replace those.  Then just put the spring, RPV, and brass fitting back in the port and carefully tap it in place with a socket. Done.

Gary: The spring is only to hold the rubber valve against the back of the brass port. So, no valve, no spring. The springs are included in the NAPA rebuild kits.