excessive crankcase pressure

[htchbck]

'93 festiva with a '95 Aspire motor (I was told, but not positive, it was in the car when I got it, but its definitely from an Aspire).

First day I drove Green Car when I got to work, I looked under the hood real quick cause there was a bit of smoke. Found a lot of oil on the pass side of the engine, up on the hood and everything. No big deal, seen it before, front crank seal and the pulley slings it. Well, it was still a little dark out, so I'd overlooked the fact that the oil dipstick was out about 2 inches. I noticed it at lunchtime. Then I cranked it up and there was more than enough pressure to blast the stick out at about half throttle. I'm guessing its due to blowby from the rings? If I put my finger over the dipstick tube and could feel the pressure building, but it wasn't ever enough to push light finger pressure away. I need to do a compression test, but my tester is at work and I'm not there today. However, even though the engine burns and spits oil, it runs great! I already replaced the PCV valve, and that made no difference whatsoever. I want to start driving it more, but the pressure and blasting oil everywhere is pretty annoying

Am I on the right track suspecting rings? I've had a couple cars with bad rings, and they've burned way more oil and never had this serious of crankcase pressure. Is it possible that the head gasket is cracked between one of the cylinders and an oil passage? Ive never dealt with anything like that before, but it seems possible it could produce these results... Guess I need to get up to work and find that compression tester lol.

[WmWatt]

No smoke out the exhaust? Burning oil usually creates smoke?

[blkfordsedan]

Same exact thing my B3 was/is doing. Never smokes out the exhaust and runs great....but blows a quart of oil out the VC breather every 200 miles. I also thought about the possibility of the head gasket leaking into an oil return passage. My only other thought was worn, broken or stuck compression rings but the oil control rings are still OK. I know I have low compression, because if I park on even a slight incline and put it in first gear, it will roll backwards and pick up speed, LOL. A a bad head gasket leak into the oil return passage would only effect one cylinder or two at the most and shouldn't be enough to allow it to do that. I ended up just plugging the PCV system and running a hose from the VC nipple into an Ebay catch can thats vented to atmosphere. I managed to get another couple thousand miles out of it, but it would fill the 950mL catch can with oil in about 200 miles. Best thing to do is perform a compression check like you said.
Either way, you'll probably end up doing a rebuild. I'm in the middle of a budget rebuild on a B6 SOHC right now...hope to have it done before the snow flys! When I get it done, I plan on tearing down the B3 just to see what the problem was.

[juryrigger007]

Check your compression. I had the exact same problem (dipstick blowing out, and oil collecting in the intake, before the throttle body.) My problem: a completely destroyed piston.
Surprisingly, I drove this, for quite some time. I had scored a parts car, with a good engine, and never bothered to look at the compression, until after I had swapped the B3 into the car. D'oh!

lesson learned...

Cheers

[juryrigger007]

Tried to attach photos...on first post. OOps!

[htchbck]

Yikes, hope its not like those pictures... Might just head down to the pull-a-part on saturday to yank a B6 out of a wrecked 323 I saw down there, if I don't see any particularly good looking B8 (wasn't last time I was there). I'll compression test in tomorrow anyway though. Would make sense if it was just one piston, why it might still run ok, though this thing is running great. Little smoke out the exhaust, but not much.

I'll post the results of compression test once thats done. May just hook my adapter (adapter is here, gauge itself is at work lol) up to the air compressor and put it on each cylinder, and see if any one of them makes the dipstick shoot out. I bet it will lol. May save a little money now and pull the offending piston and replace it with one from my parts B3.

[htchbck]

Found my old gauge out in the shed... looks like I may have found a problem...

#1: 185
#2: 115
#3: 90
#4: 180

Guess I'm going to the pullapart this weekend. Lol. Can't believe its running as well as it is though. If it hadn't been for the oil blasting out I never would have known there was a problem. I'll probably tear it down after I'm done with the swap and report back my findings.

[FestYboy]

$10 says its a head gasket....

[htchbck]

Ya know, ya could be right. It just occurred to me that the PO said that after swapping in the Aspire motor, they changed the head because "the aspire head didn't work in the festiva". I guess they didn't know you can just swap the intake and exhaust onto the Aspire head. I wonder if they either didn't properly torque the HG, or may have tried to reuse the old one (which I doubt, since there was the remains of an almost complete HG set in the trunk, minus the HG). But incorrect torque or a head that wasn't properly cleaned could cause it. Likely replacing the motor with something a little bigger in the future anyway, but I'll probably go ahead and yank the head in the morning and report back.

I guess seeing those pics of jury rigger's piston just had me jumpy lol. Shoulda recognized the two very low in the middle as a sign Thanks once again FestYboy for setting me straight! Might buy me some time while I look for a good motor for Chuck instead of throwing one at this car straight away.

[FestYboy]

hey man i just call it how i see it! i'm here for you :p

[Zanzer]

Just to mess with Arty...I'm gonna say piston LOL :p

Seriously though, it could be either.

I have a block that I took out of an 89 that had the same problem and #3 piston looks a lot like the pic Juryrigger posted. It had more oil on the outside of the engine than on the inside.

[htchbck]

Well, here's the two pics from where I pulled the head... crappy camera phone sorry in advance lol.



Definitely an Aspire head, rollers and all. And very clean at that.



Couldn't tell any difference between the cylinders themselves, none looked scarred up or anything, and with each piston at the top of its travel, none would move around really inside their bores like I've seen on some with really worn rings. And the fact that there was decent compression on both ends sounds like probably not general problem with worn rings. Head itself looked fine, as did the head gasket, but both top and bottom of the gasket was oil soaked in the same spots as the block. Maybe it wasn't torqued right? Didn't seem to be any oil in the coolant though, or vice versa. I'm getting an HG today anyway, to reinstall everything and see if it helps. $20 is a lot cheaper and takes less time than finding and installing a whole new engine lol.

Wouldn't the bore likely show some damage though, if the piston had exploded like in jury's pic?

[georgeb]

Put a teaspoon of oil on top of each piston and see how fast it dissappears. Before you pulled the head you should have done this through the spark plug hole to see if compression goes up, meaning ring issues.

[FestYboy]

htchbck; before installing the HG get some copper spray and USE IT. clean and dry all mating surfaces and apply copper spray to both sides of the gasket with a full coat (it may take 2 passes per side to get it even). torque head to 70 ftlb on the final pass with a GOOD torque wrench.

[htchbck]

Thanks Arty, I know how to do the HG, but I'm suspecting that whoever did this last HG job didn't lol.