master cylinder problem

[MCluvsacj5]

I have a small problem with my 1974 cj5. On the bottom of the master cylinder there is a small threaded
hole with a plug in it. I cannot get this hole to stop leaking. I have tried plumbers tape thread lock etc
This is the 3rd mc. I have installed, the last one was a brand new unit & still it leaks. Anyone know what
this hole is for & how I can cure this problem.

 

[superj]

i had never even looked at the mc for the 76 cj5 we had. i wonder if it had that hole also? it didn't leak though so i really had no reason to check it out. but, i do not know what the hole is for other then maybe a weep hole?

 

[superj]

nevermind, cannot be since its threaded.

no idea. i am going to google

 

[superj]

https://books.google.com/books?id=r...ded hole on bottom of master cylinder&f=false

 

[superj]

google says that is a drip hole to alert you if the seals are bad in the piston area