vacuum woes

[jerseyben]

I am trying to pin down the cause of "blow by" from the oil cap on my AMC 258 i6 / 4.2l . Its a 1980 CJ5 with the AMC 258 i6 / 4.2l , metal valve cover, weber carb, power brakes. There is 1 vacuum source at the manifold with a T going to the PCV valve and to the brake booster. All of the emissions stuff is long gone.

The valve cover has 3 holes: 1 is for the oil cap as installed. 1 just after the cap and is for the pcv valve as installed. The last hole is for a breather tube as installed.

The pcv valve has 2 openings at the "T". One T is big (3/8") and the other T is smaller (1/4").

Currently, I have the big T hooked up to vacuum to the manifold. The small T is blocked off. Then, the breather is not hooked up to anything and is basically just an open tube going nowhere.

There is a 3/8" intake tube on the upper part of the Weber that does not pull any vacuum and is blocked off.

PLEASE HELP. I know this setup is wrong, please help me make it right working with what I've got.

 

[73CJ]

Any chance you can post a photo?

Blow by is blow by and the usual cause is gases getting past the rings.

 

[Purple77CJ7]

Pictures would help. A vacuum line teed from pcv and brake booster does not sound good. There should be a dedicated line from manifold vacuum to the brake booster, and a separate line from the pcv to the carb.