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70 RR Master Cylinder - Bolt on cap or lock lever??

short stack

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Pulled the master cylinder off the 70 RR today and it is full of mud. Looking through the catalogs and I see both bolt on type lid and wire lever. Which one do you recommend?

The one I removed was screw on lid. Front disc, rear drum, NO power booster.


thanks!

short stack
 
Either one will work, just depends on your taste or if going for a "factory" look.
 
I like the bolt on less chance of a leak I got mine from Advance Auto brand new for around 30 bucks life time warranty
 
I always thought the one that has a center bolt with both reservoirs the same size is for drum/drum, those with the cap/wire bail and two different size reservoirs are disc/drum.
 
I always thought the one that has a center bolt with both reservoirs the same size is for drum/drum, those with the cap/wire bail and two different size reservoirs are disc/drum.


Need the experts to step and school me. This master cylinder is definitely two different size reservoirs. small front, larger in rear. Front Disc brakes BUT NO POWER BOOSTER.

What do I have here? What m/c do I need to buy?

thanks,
ss

btw - that screw on cap is a serious PITA...
 
Manual Disc/Drum Master 1970 Plymouth w/bail:



http://www.rockauto.com/catalog/x,carcode,1240535,parttype,1836


mc2.jpg



MC.jpg



Personally never had a problem with a bail lid leaking, but to each their own.


Good luck which ever route you go.
 
B-body was not available with manual disc, power only.
The bolt on lid cylinder is for drum brakes, both power and manual.
The one that Propwash showed above is for power disc.
 
If your master cylinder was full of 'mud' and you have the time and money it might be good a good time to flush entire line or replace if it. This will allow you to switch to paint friendly DOT 5 fluid which is not hydroscopic.The stainless lines from fine lines {http://finelinesinc.com/catalog/index.php?cPath=277) are great, just be sure to seat properly and use thread sealer if you go stainless, they also supply plug and play stock type lines. Both styles are exact factory copies including all bends and coil armor. The proportioning valve is an easy rebuild and usually holds a lot of rust/contaminants at bottom of valve, rebuild kits are available for $15 here- https://www.musclecarresearch.com/content/new-mopar-brake-valve-kit-and-rebuild-instructions.
 
B-body was not available with manual disc, power only.
The bolt on lid cylinder is for drum brakes, both power and manual.
The one that Propwash showed above is for power disc.


OK, so now Im more confused than ever. I just got done removing the firewall plate that the m/c mounts on. It looks 100% original and doesnt appear to have ever been messed with - No booster was ever on here. BUT, I see nothing that makes me think front disc brakes were added.

BOTTOM LINE - Can I run front disc brakes without a booster?

thanks

short stack
 
Yes you can run manual disc but you need the master with the larger reservoirs like Propwash showed.
I'd bet my bother in-laws left nut that disc have been added. Do you have the fender tag or Build sheet? If so what is the B code.
 
Yes you can run manual disc but you need the master with the larger reservoirs like Propwash showed.
I'd bet my bother in-laws left nut that disc have been added. Do you have the fender tag or Build sheet? If so what is the B code.


Yes, have fender tag. What is B code?

ss
 
Absolutely....Use a 1-1/32 bore master cylinder (for correct pedal travel and feel) 15/16 bore rear wheel cylinders for manual front disc/rear drum.
 
What are the numbers that are stamped or cast on the bottom of the MC do you have a pic? What size drum brakes are on the rear 10 or 11 inch? Your front disc brakes could have been added somewhere along the line and where not on there from the factory because it sounds like your MC is original
 
The one that Propwash showed above is for power disc.


Are you sure Mark? If you look at the line item for the part, it refers to manual brakes on the listing, as well as quick cross referencing of the part# against other MFG's of the master, states it as manual disc/drum master as well. Google search of A1 Cardone 101523 and checking out other sites also list it is a disc/drum master for manual brakes.

brakess.jpg


MC.jpg


I think you're thinking of A1 Cardone 191475, which is a disc/drum master for power brakes. It looks pretty much identical and is the master cylinder I have on my '69 roadrunner with power disc/drum brakes.

Pretty much irrelevant though, because you are 100% right....Manual Disc/drum brake combo's did not come as an option till 1972. That's not to say he can't make manual disc/drum brakes work with 101523 in his '70. Like you mentioned, larger reservoir, should get him there.

Good luck whatever route you go.......be it stock type parts or more of premium aftermarket parts

brakess.jpg MC.jpg
 
Pretty sure that manual disc were not available on B/E/C ever. Was on A-body. Have 2 71 Darts with factory manual disc that have this master.
 

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One of my superbirds came with a bolt on cap mastercylinder and was power disc. The brakes worked great. It sat from 72 until i bought it in the 80's so i'm sure it hadn't been touched.
 
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