TWINRAY

If's it not one thing, it's another. I bought one of the new resto PG master cylinders. I can't believe the thing seeps/leaks at the lid. I tried other gaskets and even put rubber under the gasket to get a tighter seal but it'll still eventially drip onto the rag joint. This hasn't happened to anyone else, has it?

Mike Ward

Did you install the correct OEM gasket/diaphragm? Are the spring clips tight and difficult to remove (as they should be)?

TWINRAY

Hi Mike,
Actually the clips shut easier than they should have (I know sometimes they shut so hard you need a screwdriver to pry them off) so I switched to the gasket that was on my old MC and there was no difference. I even switched clips and there was no difference. I then cut a oval section of old motorcycle innertube to fit under the gasket - now it shuts tight but still doesn't seal effectively. I just don't get it.

toddalin

My rebuilt did the same.

Drain it, take it off, seal the ports (including internal), get some fine sand paper, turn it upside down, and sand it smooth on a flat surface to get rid of the warpage and imperfections along the lip. Then flush it good.

Worked for me.

my 76 ray

I don't think that's going to help if the clips aren't tight. I had the same thing and I cut two small sections of 1/4 inch brake line and slipped them over the clips. Now there is enough pressure and it seals. If I ever come up with a better solution I'll change it but for now I'm not losing brake fluid.

chevymans 77

I ran into this on mine years back,

the rolled edge of the lid was tight on the outer surface of the master cylinder and would not let it sit down and seal of the sealing surface. I ended up working the rolled edge out a little to let the lid sit down to seal.

Set the lid on the master cylinder and see if you can move it around or if its tight and you have to force it down over the edge of the master cylinder.

If you have to force it on you will need to work the rolled edge of the lid.

Neal

TWINRAY

Thanks Neal - with my added rubber under the gasket, the fit is solid and secure with no movement.
Regards, Fred

TWINRAY

I was thinking about the top lip not being perfectly smooth. Taking it off and sanding smooth, while an option, would be a last resort - thanks for the info - glad to see I'm not alone on this

TWINRAY

Thanks - I will try this and see what happens. When I get around to placing an order somewhere, I'll probably try another gasket.

7T1vette

Stamped cover might not be flat; bails may be too loose....bend them to hold the cap on tighter.

TWINRAY

even though I did bend them before, I guess I didn't bend them the right way. I put them in a vice, got a 3 lb. mallet, and hit the top section in the middle to bend it downward. I took a short spin this am. and all was dry when I returned home. Hopefully this will cure the seepage