[Furytom]

Hi,
i got a problem with my 1996 F250 engine. I changed the oil on it on the weekend and was very badly surprised that there was only about 2 to 3qts of oil in it. The oil was only 3000 miles old (about half a year). I do not use the Truck on a regular base so its sitting around for a week or two until I drive it.
The engine has 185000 miles on it. Its running good and strong for the age and there is no smoke coming out of the exhaust. Its not leaking anywhere.
But the oil is going somewhere since it gets filled with 6qts. Now Im aware that a old engine like mine needs some oil but 3qts over 3000 miles seems to me quite excessive. What do you guys think? Were should I start investigating? Piston Rings? Head gasket?

Thanks!

[oldbogie]

Originally Posted by Furytom

Hi,
i got a problem with my 1996 F250 engine. I changed the oil on it on the weekend and was very badly surprised that there was only about 2 to 3qts of oil in it. The oil was only 3000 miles old (about half a year). I do not use the Truck on a regular base so its sitting around for a week or two until I drive it.
The engine has 185000 miles on it. Its running good and strong for the age and there is no smoke coming out of the exhaust. Its not leaking anywhere.
But the oil is going somewhere since it gets filled with 6qts. Now Im aware that a old engine like mine needs some oil but 3qts over 3000 miles seems to me quite excessive. What do you guys think? Were should I start investigating? Piston Rings? Head gasket?

Thanks!

To determine if it's smoking out the exhaust you need someone to follow behind to look. A smoke trail you can't see in the rear view mirror can easily be a quart every 1000 miles. By the time oil smoke is heavy enough to be seen in the rear view, the engine is in desperate shape.

Bogie

[Furytom]

Thanks Bogie,
I will do that today! Lets say it does smoke.
Were do I start fixing?

Tomi

[oldbogie]

Originally Posted by Furytom

Thanks Bogie,
I will do that today! Lets say it does smoke.
Were do I start fixing?

Tomi

The wonderful thing about engines is they work in strange ways, what I'll isay s often true, but not always.

Oil smoke emitted on start up and coasting with a closed throttle is usually (but not always) the result of oil being pulled down the valve guides (usually, but not always the intakes). This happens when intake manifold vacuum is high and the stem to guide clearance excessive and/or the stem seals are shot. The latter is a high probability as these things are rubber that gets hard and cracks with age.

Oil smoke coming on acceleration is usually a sign that the rings are not sealing. Cause of this is wear, corrosion, breakage, or deposits from the oil and combustion products of the rings and/or cylinder walls and/or ring lands of the piston that prevents the rings from making a seal between the combustion chamber and crankcase. A bottom end rebuild would be called for. When this is really bad it smokes when ever running.

The assumption I'm making is that if you're looking for a missing quart every thousand miles, if it isn't going out the exhaust it's going on the ground. But since you haven't said anything about puddles of oil, I assuming it's going out the tail pipe.

The Positive Crankcase Ventilation can also be a problem, when engines get old, the valve sometimes fails. The oil separator, usually inside a valve cover, gets sludged up and just passes oil instead of vapors on to the PCV valve. This is easy to look at and cheap to just replace before you dig deeper. A compression test or better yet a leakdown test can give pretty good clues to the condition of the rings and also will tell you if the valves make a seal. This test puts compressed air into a cylinder (by cylinder) the escaping air tells you how much by measurement in time to loose pressure and where 'cause you can hear where it's leaking.

Bogie

[Furytom]

Thanks so much Bogie!
Your the MAN!
That answers all my questions. A leak down test will be my start and then I can go from there.

Tomi