Messages

The seats get deformed to provide a seal when the brake line fitting is tightened. All of those seats can be removed, but I don't know if they are all the same size or if other replacements are available.

Scott,
I was looking the other day and if you search by https://www.musclecarresearch.com/parts/Chevrolet/Camaro/1969, it doesn't show the distribution block.
Thanks!!

Yes, I know. I haven't consistently added applications to that part of the catalog because I don't always know for sure exactly which valves (and associated rebuild kits) are appropriate for specific cars. Rather than guessing, and potentially selling someone the wrong item, I leave it off.

Scott, I hope you don't mind me referencing your technical article above.  Is that the right one for rebuilding the distribution block discussed here?

Not at all! Yes, that's the disassembly article. The rebuild is described here: https://www.musclecarresearch.com/gm-pd-valve-rebuild

I am rebuilding my brake distribution block. I got out the brass fitting and the spring out from the one end but am not sure how to get the piston out now. Tapping the block on a hard surface didn't budge it. I put a paper clip in the opposite end and pushed and that didn't budge it either. I know it's not's possible but looking at the end of the piston in the bore, it looks larger than the bore size.

Any advice on this. I don't want to mess something up trying to get it out.

Push with something sturdier than a paper clip, like a drill bit or finishing nail. You may need to tap on the bit or nail with a hammer.

After looking at the rebuild kit and the picture of the switch terminal on the MCR website, I thought I was good to go.  That I could rebuild my distribution block and get a new switch terminal since I broke mine.

But the more I looked at the MCR site, I am thinking the picture of the switch terminal is just there for reference. I can't seem to find it for sale on the site.......Maybe I'm not looking hard enough.

Does anyone know if MCR has these or if they are available any place else? It's great that I can rebuild the block but without a switch terminal, it's still no good.

Thanks.....Dave

Sorry, I don't sell the terminals. You might need to cannibalize one from another used valve.

I now have a reproduction of the rubber dust cap that came with this valve:

https://www.musclecarresearch.com/cap-1

$10 plus shipping.

I now have a reproduction of the rubber dust cap that came with this valve:

https://www.musclecarresearch.com/cap-1

$10 plus shipping.

I could use some help identifying a pair of original brake pressure differential switches. I've attached a pair of pictures that I hope will better explain my question.

Which of these (if either) is a 3983040 brake pressure differential switch as used on a 1970 Camaro? The only difference I can see is that the cleaner one includes a plugged fluid port in a place where the dirty one is solid. The internal parts are identical. I have two like the dirty one that I bought as advertised for a 1970 Monte Carlo (which the parts catalog seems to group with Chevelles) and a 1970 Camaro. So, what are these? What other cars were they used on?

Thanks for any insights...

Thanks for the plug, Mike!

I just posted an article that describes how to rebuild the 1970 GM 1233464 metering valve using a new seal kit that I produce. Here's the article:

https://www.musclecarresearch.com/gm-1233464-rebuild

Please let me know if any part of the process is unclear or could be explained better. The rebuild kit is available for $12 plus shipping per kit:

https://www.musclecarresearch.com/gm-metering-seal-kit-2

Orders can be placed directly from my web site. Just add the item to your shopping cart and click through the "Checkout" links. Payment methods accepted include PayPal, credit cards, checks, and money orders.

Please note that the kit DOES NOT include a replacement for the Bendix rubber dust cap. I'm still exploring my options to see if it can be done economically.

I couldn't find the thread on the rebuilding of the pressure regulator valve (I don't think there is one yet) but I have found this by Scott Hollenbeck (username here is sah62)
https://www.musclecarresearch.com/kh-multi-prop-valve-autopsy

I know of one Wagner proportioning valve used on Fords that can cause the rear brakes to drag if the internal piston doesn't move freely. I've never heard of that happening with this K-H valve, but I imagine it's possible. As noted above, removing the internal piston to bypass the proportioning function will confirm if the valve is the problem or not.

Thanks! Does it list specific models? My Chevy parts manual says all 1970 with front disk brakes. My Olds manual says 1970 F85, but strangely enough it doesn't mention the Cutlass or other models. I don't have manuals for Buick and Pontiac.

Thanks to a little help from someone at Brake & Equipment Warehouse in Minneapolis I finally figured out how to disassemble the 1970 1233464 metering valve. I just posted an article describing the process:

https://www.musclecarresearch.com/gm-1233464-autopsy

I'm working on a seal kit so it can be rebuilt. Does anyone know of any other cars that used this valve in addition to the Chevy and Olds applications?

Has anyone ever seen one of these valves that didn't use a u-cup seal where the end of the spool valve rod comes through the valve body? I recently heard from someone who found such a valve on a '69 Malibu. The body wasn't machined for a seal - picture attached.

You're welcome, Mike! With respect to reproducing the finish, take a look at this article on my site:

https://www.musclecarresearch.com/rust-removal

Products like Evapo-Rust seem to leave a grey phosphate-like coating on treated parts. I haven't tried soaking parts that aren't very rusty (like the fitting in your pics above), but it might be worth experimenting to see if you can reproduce the finish that way. If it doesn't work you can buy manganese phosphate concentrate from companies like Palmetto Enterprises:

http://www.palmettoenterprises.net/Palmetto_Enterprises/-Welcome-.html