DISAPPEARING OIL!

billybreathes

I own a 1991 Subaru Justy with 90k. Lately, I've
been noticing that the oil level is down almost
every week. I thought the car was burning oil, but
then I drove it only a little for a few days, and
it was 1/2 quart low again. I see no oil in the
driveway, and the engine is relatively clean. I
just don't understand where the oil is going.

Could it be possible that oil only leaks when I
drive the car, then when it sits, there is no leak?
Could the oil be forced out under pressure while
I drive? If so, where should I look for this?

burdawg

It has to be going somewhere. If it's not burning oil it must be leaking. Try letting it run for awhile in the driveway or a parking spot and look underneath to see if any leaks are apparent. It's not common to have a leak that doesn't drip for awhile after you shut it off, but it's possible. While it's running and warmed up, try revving the engine to see if blue smoke comes out of the tailpipe. Then shut it off and let it sit for about 1/2 hour. Start it and watch for blue smoke from the tailpipe when it starts.
These are simple things but may help to determine the cause. If you see a leak then the need for repairs is obvious.
If blue smoke comes out of the tailpipe when the car is warmed up and running, then it MAY indicate oil bypassing the rings or possibly a bad PCV valve.
If blue smoke comes out when you start it after sitting a short time, it MAY indicate oil leaking past the valve guides/seals.
Be advised though that in my opinion, a Justy with 90K miles may be close to the end of it's mechanical life, and may not be worth the repairs if needed.

billybreathes

I'll try what you said, but I've never seen any smoke coming out of the back, even when revved. I am curious though, why did you say that a Justy wouldn't last too much longer than 90k? I've always thought Subarus are built to last, and the car runs really great except the oil burning. I am curious to know if you said that because it's only a 3 cylinder?

burdawg

The only reason I said that it may be near the end of it's reasonable life is because that 3 cyl. must really be running overstressed, i.e. putting out a lot of power for a small engine. I'm not sure, just an opinion. Good luck with solving your problem.

billybreathes

the car only pulls around 1750 lbs, so I assume the 3 cylinder is strong enough. It would be the same as a 4 cylinder pulling around 2500 lbs. It's a peppy little car. My mechanic also told me that 3 cylinders only last about 90-100k. Then a variety of people on here said that a 3 cylinder should last equally as long as any other engine. It's all about the power to weight ratio (or so I'm told).

dhoff

...can last as long as any other motor if they are taken care of. My dad used to own a 1988 Chevrolet Sprint with a 3 cylinder engine. When he sold it it had over 160,000 miles on it with absolutely no engine problems.

Dave

vandad

I had a similar problem with a Dodge Caravan. The
oil was leaking *somewhere* but there was never a puddle under the car and it wasn't making blue smoke (burning oil.) I CAREFULLY went over the engine with a strong light with the engine running looking for wet/oily spots. I discovered that a gasket had a gap that was letting oil escape when under pressure. The gasket was vertical, on the side of the engine and the gap was on the top side. So, the oil didn't leak when the car was stopped. It might have splashed near the gap when the car was idling, but not enough to leak out. But, it must have really squirted when the car was driving. I cleaned the area with degreaser and pipe cleaners. (Brake parts cleaner evaporates away oil really well and leaves a nice dry surface.) I saturated a piece of string with gasket sealant. (RTV) I loosened the bolts just a bit and stuffed the gooey string into the gap. (not further in than the gasket, though...) Once the RTV set I tightened the bolts down on the string to squeeze it all together for good. It's been about a year and the leak hasn't recurred.

guitarzan

If it hasn't been mentioned, take a look at the engine coolant, and see if there is oil in it. This could indicate a bad head gasket.