Oil Consumption

[SPD TRP]

Been working out of town for a while now, the last couple of trips I have noticed quite a bit of oil consumption, maybe a quart in 200 miles. Not smoking or leaking anywhere. Wondering if seals in turbo are about out.

Maybe someone else has experienced this and shed a little light on it.

Thanks
Wayne

 

[MDCmotorsports]

Mine does the same thing. Not showing up on the ground, in the exhaust, or on the plugs.

I just check it every day and continue.

 

[SPD TRP]

Yeah man, I hear ya, but I sure would like to know where it is going.

 

[TONY!]

… the last couple of trips I have noticed quite a bit of oil consumption, maybe a quart in 200 miles. Not smoking or leaking anywhere. Wondering if seals in turbo are about out.

Maybe someone else has experienced this and shed a little light on it…

Well, if I just bought a car like that and wanted to assess it and its oil seals, I would do some of the following procedures and think of the following questions:


As far as burning it:

Valve stem seals: Does it smoke on start up? If so it is your valve stem seals.

Rings: If you do a compression test and or a leak down test, you can get an idea of what shape your rings are in. From that, you can sort of gauge the sealing of that area.

Turbo seals: I once hear this mechanic tell me that if your turbo is damp on the outside, then that means that one of oil seals is bad. Possibly if your turbo’s seals are bad, you will get quite a bit of carbon build up on your pistons. I think that is the reason why my pistons had an excessive amount of carbon on them, from oil entering the cylinders.



As far as leaking it:

There are two types of oil leaks: the ones that drip, and the ones that don’t. You can have an oil leak that runs down the engine and sort of evaporates. If you have multiple leaks like this, collectively running down a large surface area, you will loose a bit of oil and won’t even see it on the ground.

Valve covers: Having a leak like that in the valve covers would be that way. The leak would have to run the height of the engine before it reaches the ground.

Cam position sensor: On my car it was very black and gunky in that area. The CPS has an O-ring that shrinks after so many years and heat cycles. A leak in an area like that (high and around other parts) would get everything damp and evaporate rather than leak—if it is a small leak and not gushing out.

The front cam seals: They are also very high and would run in the timing case and get many things wet and evaporate before reaching the ground.

There are also other places/seals that can also contribute to oil loss, but I just named the ones that I suspect the most for "invisible" leaking.


On an old car with drying out rubber gaskets—and so many of them—it can all add up to quite a bit of oil loss without even dripping on the ground.


Those are my thoughts and theory on the matter so far and what I have come up with.

 

[SPD TRP]

Its not the valve stem seals because I changed them when I changed the head gasket and sealed with ARP studs. Changed timing belt, CPS O ring, both cam seals, as well as cam cover seals. If I had a leak, even if it didn't reach the ground, there would be evidence on the motor or other components.

When I take off the accordian pipe, there is always a little puddle of oil resting on the inside of the turbo where the pipe fastens.

Just wondering if anyone had any ideas.

I appreciate your response.

Thanks

Wayne

 

[isnms]

Rings: If you do a compression test and or a leak down test, you can get an idea of what shape your rings are in. From that, you can sort of gauge the sealing of that area.

do a leakdown test

 

[MDCmotorsports]

Wayne:
That sounds to me like a bad front turbo seal or a wild PCV system.

 

[SPD TRP]

Wayne:
That sounds to me like a bad front turbo seal or a wild PCV system.

Kinda of what I thought, but I don't get any smoke on decel.

With the turbo car before this one, when the turbo seals went out, it would smoke like crazy on decel. I wonder if my intercooler is filling up with oil.

Probly take it off tomorrow and check it.

Thanks
Wayne

 

[TONY!]

The way I see it is like this, when you lose oil on a consistent basis, it can only be two things: you are leaking it externally (either the type that drips to the ground or the type that runs all over and evaporates because of the hot engine) or you are burning it--it is that simple.

I had the same situation in my car, although I hate to admit it.
I attribute my oil lose due to oil seal from which I could see the oil all around when I took it apart.

I once read in a manual that a car's oil level can drop if it has been used for short trips for a period of time (where it accumulates moisture), then driven for a long highway trip. Supposedly the long trip drive would burn off the moisture making it appear as if the oil level has dropped. (I am 80% sure I read that in the Supra owner’s manual [not the TSRM]).

If you are losing your oil to the intercooler, there is only so much that can store. I really don't think that all that oil is going to the intercooler and staying there.

How much a car goes through oil is a sure sign of its age and condition. If you don't consume oil, that is an excellent sign. Knowing that, I was very concerned and did wonder for a long time where the hell that oil was going.

I don't want to appear to be contradictory or argumentative, but this is an interesting and important topic to me and maybe others as well. I wouldn't have come back for a moot point. If I were to ever build an engine and lose oil on a consistent basis, I would be upset, just as I would be if I bought a car and found that it went through oil as well.

Maybe it would be interesting to do a poll and ask how many quarts are consumed for each 1000 miles of driving.

 

[Spiv]

Right along the same lines, (not to hijack, but...) I think I'm losing a little through the CPS o-ring, as well as a turbo seal. I'm also seeing a little on the ground and on the front crossmember, looks like it's coming from the front crank pully. This stuff started not too long ago, could it all be related, and what kind of time/money would I be into for fixing whatever the crank pully one is?