oil change mineral to synthetic

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Mon 29 Sep 2003 14:01
oil change mineral to synthetic - prelude
I have changed from mineral to semi sythetic on our H reg corolla 2e engine. Now have lots blue smoke from the exhaust.

Any thoughts?

garage has said valve stem seals are too old to cope with chemical change and need replacing.

Did I do wrong?

Thanks
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Mon 29 Sep 2003 14:21
oil change mineral to synthetic - Vagelis
Your engine may be too old to cope with ultra-thin synthetic oil.

I'd say no harm, just change back to mineral.

Vagelis.
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Tue 30 Sep 2003 11:37
oil change mineral to synthetic - Ian D
Did you stick to the same viscosity (eg 10W40), if not part of the problem could be due to perhaps a lower viscosity (thinner ) oil creeping past the seals.
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Tue 30 Sep 2003 12:08
oil change mineral to synthetic - rg
Synthetic oil will find it's way past seals of all kinds.

You may have a new "footprint" on your drive soon...

I would go back to mineral as you are not gaining much in terms of protection with an engine of that age. Better to burn something cheaper!

HTH

rg
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Tue 30 Sep 2003 18:17
oil change mineral to synthetic - Dizzy {P}
Confusion here. The subject is "... synthetic" but the body of the original message says "semi synthetic"

I would agree that there is not much to be gained by changing to fully-synthetic on this car, and it could lead to oil leaks, but semi-synthetic *might* be a different matter. Which is it?

Incidentally, rg, I don't agree that "Synthetic oil will find its way past seals of all kinds". My 1992 BMW ran with synthetic oil and there wasn't a trace of an oil leak at 120,000 miles, not even a smear.
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Tue 30 Sep 2003 19:58
oil change mineral to synthetic - z
Synthetic is very good at leaking, but can be defeated. I used Mobil 1 in a Mitsubishi Sapporo, the cam cover gasket would always seep, although I could get temporary relief with gasket adhesives. I now use Mobil 1 in a Honda Civic with 125k miles on it, doesn't seem to leak at all although it does seem to use some oil at a very slow rate.
Do you have any of the various newer oil formulations advertised for elderly engines available in your area? They are supposed to be endowed with extra doses of seal swellers and other additives to benefit the rickety old machine. Alternately, cans of just seal swellant oil additive are available; although I personally wouldn't recommend this particular combination of worn engine, synthetic oil, and seal swellant as some kind of optimum setup.
(Parenthetical aside; the one time I tried a can of that stuff, the next time I tried to remove my personally hand-tightened by myself 3 months previous, normally simple to remove oil filter, it was so tight that I broke the weld in my oil filter wrench, and ended up delivering the car to a garage to deal with it. They eventually got it loose; there was no crossthreading or anything else wrong, it was just good and stuck. I feel the two unusual events (use of seal sweller, unremovable oil filter) are most likely correlated. So, I presume the stuff at least does make worn leaky rubber seals swell up effectively, as advertised. Unwanted side effects may result, however.)
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