Disappearing Oil

[aimee0]

I recently purchased a 1994 Geo Metro 3cyl 5 speed. It uses about 1 quart of oil every 500 miles. I have seen oil around the air filter(in the breather). The engine doesn't smoke or knock. I was hoping it could be as simple as a PCV valve. Any ideas on what could be causing the oil to disappear???

Also the little thing still gets 49 miles per gallon on the highway....

[geozukigti]

It's probably burning oil on the highway. They tend to do that when the engines are getting worn out. You may never see smoke, but it's burning a ton of oil when it's revved up on the highway. Piston rings are most likely worn out.

[aimee0]

geozukigit,

Would it still have good power with rings worn out? Car has only 100,600 miles on it as well. There is some oil in the breather, what would be causing this???

[geozukigti]

It will still feel ok if the piston rings are slightly out of tolerance. Oil in the filter housing is mostly caused by a combination of a bad PVC, and blow-by in the cylinders. If compression is leaking past the piston rings, it's gonna come out the PCV. If enough pressure is going by the rings, it will be pushing so much air out of the PCV, it won't ever close. So then oil will start to come out and soak the filter and airbox. Do a compression test to be sure. Take all the plugs out, screw the compression tester to one of the cylinders, and crank the car for 5-10 seconds with the throttle wide open. Read the PSI, and then check the next cylinder. Now, put about a cap-full(oil bottle cap) of oil into each cylinder and do the test again on all of the cylinders. If the PSI goes up, it's bad rings. If it stays the same, your valves are leaking compression. Stock compression is 185psi. Your valve seals could also be leaking oil. Does your car ever blow a small cloud of smoke out of the tailpipe when you start it in the morning?

[aimee0]

I haven't noticed any smoke when I leave in the morning. I'll have the compression test done and let you know how it turns out. It will probably be several days before I can post the results. Thanks for your help.

*** 06/08/2005
I replaced the PCV valve and there doesn't seem to be any oil in the breather any more. However, its still using oil pretty bad.

[aimee0]

Originally Posted by aimee0

I haven't noticed any smoke when I leave in the morning. I'll have the compression test done and let you know how it turns out. It will probably be several days before I can post the results. Thanks for your help.

*** 06/08/2005
I replaced the PCV valve and there doesn't seem to be any oil in the breather any more. However, its still using oil pretty bad.

***07/18/2005
I have completed the compression test.
Cyl #1 145psi
Cyl #2 85psi
Cyl #3 150psi

after putting in a cap of oil
Cyl #1 150psi
Cyl #2 90psi
Cyl #3 210psi

I think I have all sorts of engine problems. I am getting rebuilt from a local mechanic in the NE AL area for $425. New rings, valves, rebuilt head, timing belt etc...

[geozukigti]

Your engine should be pronounced dead on the scene with that compression! Heh. That's an excellent price on a fully re-manned engine. Your car will run awesome!

[Infinitrium]

The 93 4 door hatch Geo I had last year had almost identical compression, cold dry numbers were 145,145,90. I still got mid 30's in town, mid 40's on the highway at 68-70 mph.

[aimee0]

geozukigit,

I thought it was a good price as well. This mechanic works mainly on metros as a hobby. He doesn't do this for his main income. I live in a little town called Sylvania AL and we have a Metro specialist . I was very surprised. He told me it would be two weeks before he could get to it. I'll let you guys know how well it went???

[hodunwun]

That's one of the beautiful things about metros ie how cheap the can be run. FYI, crate suzuki 1 ltr engines from Japan can be had for $375 out here in Washington. That's with 40 grand on them. Tested and Certified. I buy metros at a charity auction and refurbish them. Now, however, there are no more available at the auction sites. Wonder why????

[aimee0]

I have driven about 1K miles on the new engine. It runs great. I can pass, even at 70 mph. Definetly recommend an engine rebuild.

[ubernerd]

Thanks for that info.
I have over 300K miles on my Metro (98) and i think i will be needing a new or used engine... but it has been using the same amount of oil since i bought it... it mostly leaks out thru bad gaskets (crank pulley seal, valve cover gasket, oil pan gasket).
As an alternative, does anyone know a good place to get good quality ring kits? I'm not sure wether to redo or replace.

[GoogleThis]

When was the oil changed last?

I know on mine when I got it, it burned 2 quarts in the 600 miles before I could change the oil. Since I changed it, I haven't lost a drop in over 1000 miles.

[elionwyr]

Question:

I'm also having the disappearing oil issue and it sounds very similiar to what was described in this thread.

Humour me. How bad is it to drive an engine with bad pistons?

[geozukigti]

Bad pistons.... The car wouldn't run at all. Bad piston RINGS, the car would be sluggish, burn oil, the oil would be nasty at oil change time, bad MPG, smoke from the exhaust..