Hi all! I'm hoping you folks can help me out. I just bought a 89 xj with an interesting intake setup and I just finished driving it back about 400 miles fromj where I picked it up. Along the way i noticed that it was leaking oil into the air filter at the rate of about 1qt per 50 miles. It was a real mess! The previous owner said it had to do with too much vacuum being created by the Airmax installed on the system and he had built this contraption to collect it (basically some kind of box from a dune-buggy that would collect the oil and funnel it into a tube attached to an empty oil bottle) but it wasn't really collecting much oil.

I have heard that it may have to do with CCV of PCV but I'm not really sure what this is as I'm a bit of a noob to jeeps. I've attached some photos of the setup he made as well as a few other related photos. I'm kinda dseperate to get this fixed cuz this'll be my daily driver. Thanks for your help!

 

♠The PVC valve is the rear valve on the valve cover. It will make your jeep run rough when it gets clogged. The CCV is the first valve on your valve cover.This has a small hose that connects to air filter case. The ccv will leak the oil into your air filter once it is bad
But i dont know anything about that setup or where the hose has been re-routed

 

the lager front hose/tube is the fresh air intake,the smaller is the vacum line on the rear of the valve cover.Make sure that the rear line isn't plugged,if the crank case builds to much pressure it wiil push excess oil out the intake tube.

 

nice looking setup tho

 

Any other ideas... input?

 

Blow-by will also cause oil to be pushed into the air cleaner. Broken ring is the usual suspect.

 

My 89 had a LOT of positive crankcase pressure, most likely from worn rings, and it pushed enough oil into the air box that it'd run out the bottom and all over the exhaust when I stopped on an off ramp. Smell was terrible, and always had a case of oil in the back to top it off, and enough fire extinguishers on hand 'just in case'.
Cleaned the baffles in the valve cover, which didn't do much but stop the oil leaks around the cover, even capped the vacuum line and put filtered breathers on the valve cover, which just let the oil run all over the top of the motor.
After fighting the oil situation, and busted coolant expansion bottles for about six months, I found a fresh motor, and the oil problems went away. I sold it before I got round to making a closed coolant system.
Run a compression and vacuum check on your motor, and try to determine what kind of shape the motor's in. Hate to say it, but you're likely in for some major work, because the oil problem is just a symptom.

 

Well, I did some looking around this morning and discovered, much to my disappointment, that there is in fact a large amount of blow by coming from the motor. With the vacuum hose from the valve cover removed, I saw a steady stream of blow by-exiting the engine via this port. BUMMER! I am gonna be installing a new motor from S&J engines from Spokane. Gonna be kinda costly but I guess that's what it takes.

I also saw that the previous owner has installed an enclosed radiator system as well. aI have heard that this can sometimes cause vapor lock after draining if not primed correctly. Anyone know about this?

 

87 to 90 jeeps come stock with the closed cooling system,just make sure you burp it real good.

 

most likely the CCV is the culprit [edit: i don't know what the heck it is] but i just wanted to comment and say that under the hood that thing is looking very clean with lots of new (looking) parts

 

If you truly want to know whether you need an engine, do a "leak down test".

Anyway, my big plan...before a mechanic simply tightened up my torque converter bolts and my "piston slap" disappeared, was to leak-down test it. Now I don't care...it runs fine and makes good power.

But for your engine, nothing will educate you like a leak-down and they are easy to do if you have a helper to bump the starter for you to get the pistons to TDC. That is the hard part...after that the tester itself is very simple.

With a leak-down you can tell whether it is rings, intake valve or exhaust valve or blown head gasket all from one simple test. Then you'll know what to do next. Maybe it won't include a new engine. Maybe a short block, maybe a head gasket, who knows. Leak-down is like an x-ray.