Switch to full style
From Tune Ups to Oil Changes, maintenance related
Post a reply

St165 Valvecover breather orifice pcv etc

Fri Nov 01, 2019 2:38 pm

Hello,
What is the modification for the oil baffle in the valve cover?. I dont vent enough and it's putting oil in the pipe.
I was going to put an air water seperator inline with a drain back to the damn pan. I just rebuilt the motor, didnt test any numbers yet. With the oil cap off theres an obvious pulse coming out.
Members don't see the above ad. Register now

Re: St165 Valvecover breather orifice pcv etc

Sat Nov 02, 2019 12:55 pm

On the surface, it sounds like you are getting too much bypass from the rings to the crankcase. Rebuilt engines that haven't been broken in yet will do this. Engines improperly rebuilt will also do this. I would tend to recommend you find out why your engine has excessive bypass and deal with that, rather than accept the excessive bypass and try to resolve the oil carryover caused by it.

Re: St165 Valvecover breather orifice pcv etc

Sun Nov 03, 2019 1:17 pm

Yes I understand. I did read on here that someone had to drill the louvre out on the baffle under the cover.... who has done this? They studied the engineering and found that vent was insufficient. I will check compression later in the week. I used the ATS break in method. I measured the bores. I used the Chinese pistons because the engine builder here said they're fine he uses em all the time. Cold starts like a champ. Does fine until 5000 rpm.
Post a reply