Noticed my motor was 1 quart low after not quite 2800 miles since oil change. Not burning it or leaking it-engine dry underneath (including rear main, which after being rear-ended at freeway speed amazed me). Talking with some folks about it and one guy says my valve seats may be worn and the engine is "bypassing oil". I don't see or smell any smoke out the tail pipe at idle, but sometimes some "whispy" white smoke (although it's not really smoke, and it kinda floats out which makes me think it is not from the engine but maybe the glass pack?) comes out the pipe. Anyone have any ideas? Before the wreck the pinto rarely needed oil. I will continue to monitor it but find it hard to believe that my valve seats are on their way out already.
Didn't Martha sit for quite awhile before her resurrection? If that is the case, then it's possible that the valve seals are weak. The primary symptom of this is a puff of blue smoke out the exhaust at startup (but you knew this didn't you?) They also cause slight oil consumption. Nothing remarkable, but really more irratating. If it's using a quart between changes, that's more than acceptable, it's actually repectable. Especially for a 30+ year old engine.
If you're SURE it's not the seals, then look the engine over carefully. If it's leaking you'll see it, no matter where it's coming from.
By the way, if it's "bypassing" then you'd have low oil pressure & no oil loss. Bypassing indicates that the oil is going around the galleys & bearings, not out of the motor. This would indicate a severely worn, or damaged engine. & Martha doesn't sound like she's hurt that bad.
Crazy,
Yes she did sit for 4 years and I didn't start her at all during that time but did put a wrench on the crank and turn the engine over by hand. I suppose the valve seats are weak. She doesn't blow any smoke at all at start up (except for black smoke if you rev her up while sitting-just little puffs of black smoke and it is gas I'm sure because she is running rich. You can smell the gas and when you wipe the inside of the tailpipe it's sooty). However, my man says that it puffs blue smoke when I shift-I assumed that it was gas, although I know blue smoke is oil-I'm in denial- because I don't smell any oil and it is only when I am shifting that he can see it. I have never seen any blue smoke come out and he says it is just a tiny bit. Positive she is not leaking oil. Looked her over real good. I had never heard of bypassing oil and that is why I wanted to solicit input from my fellow pintoers. Martha's engine has high miles but lots of life left. I always took real good care of her and have never had a problem with this engine. It's clean and strong. Maybe the engine is just burning the oil when I shift??? Has anyone run into this situation before? Thanks for your information crazyhorse, I appreciate it very much.
My '88 Mustang 5.0 burned a quart of oil every 3 thou even when brand new. When the check oil light came on I knew is was a quart low and time to change the oil.
This brings up a related question, something I've always wondered: Does a catalytic converter burn up oil smoke before it gets out the exhaust pipe?
I.e., if your car is burning oil, is it going to go through the catalytic converter and come out blue, or will the catalytic converter 'mask' the problem by burning up the blue smoke so the exhaust still looks clean?
I guess ol' Martha just likes the oil. No performance issues, no smoke, no smells. It must be that she just needs the lube. I have to get used to her again. My 75 F250 pickup has a zillion miles on the engine, 3 low compression cylinders and I hardly ever have to put oil in it-but then again, I don't drive it 6 hour round trip to the doctor!! Thanks for your input. I feel better. I can't comment on the catalytic converter as I am not very familiar with them.