[Pops @ Tri-5.com]

Need to replace the M/C on the '55 that I just picked up.....As you may be able to see in the photo, it is leaking past the secondary cup.....Anyone know where this one may have come from?

 

[acardon]

It looks like the A/C Delco part # 18M293 from a 83 Malibu station wagon. You might want to take it apart and measure the bore. Rock Auto listing....http://www.rockauto.com/catalog/x,carcode,1055461,parttype,1836

 

[Pops @ Tri-5.com]

Sure looks like it Don....Now I'm thinking that the PO put a front disc brake M/C and proportioning valve on a car with drum brakes all the way around :confused0006:

 

[Pops @ Tri-5.com]

Here's a shot of the proportioning valve:

 

[Pops @ Tri-5.com]

Maybe it would be possible to replace the M/C with this one: http://www.classicchevy.com/chevy-dual-brake-master-cylinder-with-power-drum-brakes-1955-1972.html

And the proportioning valve with this one: http://www.classicchevy.com/chevy-disc-and-drum-brake-proportioning-valve-1955-1981.html

 

[acardon]

Those should work fine. That also looks like the valve that was on the 83 Malibu that I inherited from my dad. I parted it out. I kept his 41 Dodge though. Future project. ......

 

[Pops @ Tri-5.com]

That '41 looks like a good project Don :tu