1983 Jeep CJ7 Oil blowby/crankcase ventilation

DAMMONS

MEMBER
1983 JEEP CJ7
6 CYL
4WD
MANUAL
15,600 MILES

I installed a reman engine on the CJ7 due to excessive oil blowby and all cylinder compression was down. I still have blowby but compression is good. All smog had been removed when I bought it and it initially had a PCV valve line routed to the carb and a breather cap with a vent line going into the rear of the intake manifold. I removed the PCV valve and plugged the hole and routed the vent line from the breather into the intake. It cured the oil leaks but it drinks oil at the rate of a qt. Every 150 miles and smokes some between shifts. It has an aftermarket Weber 2bbl installed on it. Is there some other way to get the proper ventilation to stop the blowby without having the intake vacuum suck the oil out of the top end? Thanks.

1 Reply

2CARPRO JACK

MECHANIC
11,533 POSTS

You need to put the pcv back to the way it was stock. The way you have it, the intake vacuum is sucking oil right out of the engine. With the breather back to stock, how many miles on the new engine? Takes them a while to break in sometimes. Be patient and keep track of the mileage to see where you are at as far as break in goes.