'High mileage' oil?

[RETed]

High mileage engines (not just rotary) usually smoke due to higher-than-spec tolerances on seals and o-rings.
This is your "wear & tear".

These "high mileage" oils tout they are better cause they have specific additives.
Bunch of bullshit.
There is no (good) additive that can magically "seal-up" and engine to minimize or prevent smoking due to excessive blow-by from worn seals.
Be careful of "stop leak" products that claim this - you will usually hurt your engine rather than help it in the end.

Old-school trick is just to run thicker viscosity oil...
If you're not running 20W50 by now, try it...
Smoking will noticably decrease.
No magic in that - thicker oil will not leak as much past seals versus thinner viscosity oil.

At over 200,000 miles, your engine is probably in it's golden years...
I put money the oil control o-rings are degrading pretty badly by now.
Easy test for this is to rev the engine in neutral to about 4k RPM - I bet you get copious amounts of smoke out the exhaust in about 10 - 20 seconds?
If this is the case, nothing short of a rebuild (to replace those o-rings) will fix this smoking problem.
No special "high mileage" oil will help this problem.
A stop-leak product might stop the smoking, but you'll probably end up ruining the engine anyways.

This is where diligent maintenance could extend the life of the engine.
Do religious oil changes at a minimum 5,000 mile interval with quality motor oil.
Do engine cooling system flushes every other year.
Do not overheat the engine.
With just those 3 simple rules, you can get a 13B to run 200,000 miles...maybe even up to 300,000 miles without cracking her open.


-Ted