1939 Dodge D11 6 Master Cylinder

[Guest BlueBare1]

I'm having trouble with the packing of the MASTER CYLINDER. The New Old Stock Master Cylinder I've obtained from Andy Bernbraum Auto Parts surley required a new kit but the problem is that after seventy years the packing will not hold (leaks). Is that someway to fix this problem where it would work under pressure?

[Pete K.]

If it's a NOS part, indeed the rubber is gone by now. I'm surprised Andy didn't mention about a rebuild kit for it when you purchased it from him. He is very knowledgeable. There is no "packing, per se. The rubber cups are the sealing points on the piston, whereas you have what I think is a Lockheed double piston type master cylinder for your car. One should always coat the new parts going in with a liberal amount of brake fluid first. You also should have a .001" - .005" clearance between the "bare" piston & bore of the master cyl. This can be checked with a blade type feeler gauge. Anyway, call Andy.

[Guest toybox99615]

The best long term fix I know of is to have the cylinder bored and a sleeve inserted. I've used White Post Restorations for a lot of master cylinders and wheel cylinders services. They give a lifetime warranty on the work. Over the years I've probably sent or referred a dozen jobs to their shop. A couple of which were very unique cylinders from a tug boat shaft brake. They have always treated me fairly and expediently.