71 Master cylinder rebuild--what's the trick?

[Mike E.]

I'm trying to help with the rebuild of an original 71 m-cylinder. Having trouble getting the rubber cups to fit down the bore. I can get the first one started, but then it hangs up in the groove for the snap ring. I've not had problems with all the C-1's I've done, but this one seems to be smarter than I am ( relatively easy feat). What's the old guard's trick?
What am I missing?
Thanks!

[Joe L.]

Re: 71 Master cylinder rebuild--what's the trick?

I'm trying to help with the rebuild of an original 71 m-cylinder. Having trouble getting the rubber cups to fit down the bore. I can get the first one started, but then it hangs up in the groove for the snap ring. I've not had problems with all the C-1's I've done, but this one seems to be smarter than I am ( relatively easy feat). What's the old guard's trick?
What am I missing?
Thanks!

Mike----


Has this master cylinder been sleeved? Sometimes, the master cylinder "sleevers" leave no chamfer on the end of the sleeve. This can cause the problem you describe.

[Michael G.]

Re: 71 Master cylinder rebuild--what's the trick?

Mike,
You might try to roll a tube from "paper thin" good quality plastic sheeting. Have it overlap slightly (not several times). insert into cylinder, just enough to get you past the groove, lube plungers lightly and insert into tube. Once fully inserted, extract plastic slowly. Good luck. Mike