Crank case breather box leak-- ugh. Fresh oil change as the culprit?

[billschroeder5842]

I think I have a crank case breather box leak. I looked under the car a couple of days ago and found about "two drops" worth of oil on the floor. I crawled under the car today and after some light wiping from oil over spray at the back right of the engine, i see the breather box "vent tube" had some oil on it.

I read the sticky on LT5 oil leaks and see that the plenum has to be pulled to get at the six bolts and some clamps for retightening.

Before I jump into a plenum pull, I have a question: I had the oil changed about a month back and about 250 miles before I noticed the leak. Would the breather box leak if the oil was slightly over filled? I've never has a problem before and I have heard (rumored?) that LT5s tend to "burn off" a fresh oil change before "settling in" after 3/4ish of a quart is lost.

Wishful thinking or do I "nut up" and pull the plenum?

[Hib Halverson]

When I owned "Barney", my '95, during the whole 20 years I had the car, I had only one oil leak problem and it was that darn crank case breather. Over a period of time the fasteners loosened enough that there was no more clamping pressure o the gasket.

Pulled the intake. Tightened the bolts to spec.
Problem solved.

[billschroeder5842]

Thanks Hib. I've never done "the pull" yet so I'm reading stickies, shop manual and You tube.

Question..... everything I've read say to disconnect the fuel lines, but my (untrained eye) can't see a connection to the plenum pull. I'll follow the directions of course, but cant see the connection?

Oh, I'm "reasonably handy"... how much time should I allocate for a first time plenum pull? Is this an afternoon project or plan a couple of evenings after work? Looks about 2.5-3 hours-ish, but then again friends and beer will be involved....

[billschroeder5842]

Well, I started and completed the plenum pull this afternoon. As Hib suggested, the crank case breather had three of the bolts that were seriously loose.

Big thanks to Steve Schroeder (Cross Flags Performance) who took my call and talked me through some of the "do's and don'ts of the plenum pull and had me check a few extra details-- he was a big help.

Also, my buddy Wayne (who has a 90 ZR1) just happened to have an extra OEM type gasket from Jerry's (How lucky can you get?!) and came over to give me a much needed hand and adult supervision.

It took us both about 2:30 minutes from start to finish. It was pretty straight forward and the engine started and ran as normal. I'll keep an eye out for leaks but so far so good!

[Ccmano]

Good work! Torque those injector housing bolts while your in there. Probably an even more neglected item than the breather box bolts.
H

[jss06c6]

ZR-1 merit badge for you two! Well done Bill.. you could have finished in 4 hours if you had skipped the cold suds!! [emoji41][emoji41]

Sent from my SM-G950U using ZR-1 Net Registry mobile app

[Hib Halverson]

Bill...way to go dude! You're now a member of the PPS (plenum pull society).