Oil burning off in engine compartment

[brian bramble]

Hello Porsche people,

I've posted before regarding my 75 911s, that had an engine fire some 13 years ago.

Now I have her running again but still have plenty of bugs to work out.

The bug that's bugging me the most right now is the oil burning off the engine and exhaust and heat ex's. I've had her out trying to run a fuel additive through her as well as burning off the accumulated oil. There is still some sputtering in the lower rpm's but seams to be getting better. I've driven 2 times each for about 15-20 minutes. I get nervous with smoke burn off , as another fire would break my heart. Question is , should I keep driving to burn off the residue . I would hate to mess up the paint by the smoke burning off as well. I'm pretty sure the leak is from valve covers . Should I try to re-torque (if so , how much ) or should I start replacing gaskets all over ?

[EC900]

Hopefully the engine wasn't overfilled with oil.
If it’s cover gaskets leaking, I’d replace them, of course check if covers are flat and not warped by placing them on a granite countertop.
And since they’re off may as well check valve adjustment and proper oil change fill.

Sure, in meantime you can try to torque covers and see if it alleviates the problem. Some say 6nm but others say 10-15nm depends on gasket type. See what yours are at before replacing will get you in a ballpark.
Keeping in mind a combination of things may be leaking so cleaning off the engine grime before it really bakes in will be needed. Clean engine = cool engine.

A common problem during long storage, oil seeped into the cylinders via worn valve guides you’ll see substantial smoke coming out of the tailpipe. This type of oil burn off lasts anywhere from 5 -15 mins. Theres nothing to worry about get it up to 190° to clean the injectors and any accumulated moisture in the oil, but a much longer drive, 20 miles or so, highway speed better.
So yes drive, it’s the only way to get rid of oil residue maybe sitting inside the HE’s. Annoying and stinky but necessary. You may want to disconnect the hoses to the heat flappers so burning oil fumes don’t enter the cabin. They’re not airtight.

[stownsen914]

Take a good look for engine oil leaks. You could also give it a good cleaning with engine cleaner and a good spray with the garden hose if there is residual oil. Having it clean can help find new leaks in case you have one.

And yes, oil in cylinders from sitting can smoke for quite a while (it can even get into the muffler in some cases and smoke even longer), that would be out the exhaust of course. You don't mention smoke coming out the tailpipe.

[Duc Hunter]

My 3.6 recently was restarted after a year in the body shop, and work on the oiling system etc. No leaks, and smoke was coming off the headers etc even after several 20 min idling sessions while checking the oiling and oil cooling system. Mind you there was not a lot of smoke like a mosquito fogger, but it was there. All gone now.