holy "SMOKES" in my 1979 SC - advise please

[FinallyGotOne]

so I just don't fully get what the heck is going on with my 911. I 'm almost to the point of leaving it up at the shop to diagnose.

I drove it the other day quite mellow. And it drove quite well. When I pulled up to the stop lights no issues all is just peachy.
The next day I was in a hurry and drove her harder. Hard on 1st then second gear. and higher revs in 2nd gear mostly. Then when I pull up to the same stop light as I'm idling there - smoke billows al around my left and right side. Not a heavy black smoke, a lighter grayish smoke. as I revved it more smoke came out. then nothing the rest of the 5 mile drive home.

I am thinking this is oil cooler related. I am curious though why harder driving makes it smoke any more than normal driving. what do you all think.??

It smokes at start up too for a bit. But isnt smoke from wornout rings bluish not grayish black?

Maybe I'll post a video and see if that helps you all to diagnose.

[crustychief]

Maybe the oil level is a tad high?

[FinallyGotOne]

i'll check thattonight, good idea.

[Mattlock18]

My 83 did the same thing a few years back. Everytime I came to a stop it looked like I had a James Bond smoke screen going. I ended up having to replace the oil cooler.

[FinallyGotOne]

eeks. think thats a $1,000 repair, unless anyone has better info on a 79??

[pete3799]

Had the same problem.....leaking oil cooler dripping on the heat exchanger.
Climb under it and see what's leaking.
Used oil cooler (175.00 IIRC) fixed it.

[Bear911]

Is the smoke coming out of the exhaust or burning off the heat exchanger? I had a similar issue a while back, turned out to be the idiot oil switch, spraying oil everywhere and dripping on the exchanger. Cheap fix in my case, but a PITA to get to (no engine drop required though)

If it isn't coming out the exhaust, it's time to get a torch and some small vanity mirrors and go leak huntin'.

Good luck!

[Paulporsche]

Any burnt oil smell? Could you have a leak onto an exhaust element? Leaking oil pressure switch?

How long since you last drove it? Could you have condensation in the exhaust?

How about your mixture?

[motogman]

Agree with other posts that leak is a likely cause.

When you drive gently it doesn't heat up enough in the short distance to the light to start to burn off. When you push it it does get hot enough.

After the first light it is still burning off but if you are not stopped only the people behind you notice...

[Plecostomus]

Is your emergency brake off?

[FinallyGotOne]

Okay, so I drove her again today, Pretty much stayed around 2-3K RPM the 20 minute drive to work. Much stop and go. Never smoked one bit. Drove perfect. enjoyable. Outside temp was also a bit cooler.

A week or so ago when I had the rear bumper cover off I sprayed brake cleener under the left side valve covers and heat excahngers. and everywhere I could get to. I did not focus as much on the passenger side though, but did try and clean off the oil reserve case on that side while I could get to it easy before putting on bumper. that was caked with oil.

I may need to get one more can of that stuff and hit my passenger side exhaust.

Really hard to see where it is coming from as it always seems to come around and waft past the front of my car. My plan is to drive it hard on the way home and hit a parking lot to try and figure it out. But maybe the good news is that it isn't coming from the exhaust pipe eh?

[FinallyGotOne]

911 Possibly Internal Oil Cooler Leak? - YouTube

Video of smoke. The video does not really catch the smoke that well. but you can see that it is burning off the bottom of the exhaust - is this where a internal oil cooler would leak down to? I will try and get a better video. I still need to get that brake cleener on it and clean it up so I can see how fast it gets smoking again/.

[sailchef]

If you look at the left side of this engine you'll see it is all wet from oil. The breather gasket and oil pressure seal were the main culprits along with a couple leeky cooler seals. Its leaking all over the exhaust/heat exchangers. I had the same cloud of smoke at every stop light like you have described.



The oil from the breather also ran down on top of the cooler and clogged it up pretty good. It then ran down onto the exhaust.

This is my oil cooler before cleaning the cooling fins.




After cleaning and installing new seals.



I would put it up on a lift to start, and take a look around at the underside of the engine. It might be leeking more than you think. Pulling the motor and changing seals and gaskets is realitively cheap if you do it yourself.

Try reading this

Pelican Technical Article: 911 Oil Leak Fixes

[FinallyGotOne]

Do you have your 911 back together now? i did address leaks last time we had the engine out. But I don't really have the means to pull the engine myself. So It would have to go to the shop for that. I may save up some money to get this done. i am not totally sure about this whole internal oil cooler?? I did not know you could access it and clean it off... Think your right, seems we'll need to get it up on the lift/ Thanks for the pix!

[FinallyGotOne]

OK, so finally decided to take this car to the shop to get advice on the leaks. When we had it up on the lift and gunned the throttle, there were drops of oil that would come out consistently right below the oil cooler. I was told it is either a seal or a plug or something but gotta drop the engine. I'm hesitant to do this now as I am unsure how to proceed with the oil cooler. they are over a grand new, only $300 used, but the used one can be problematic in no time. Seems the way to do it is with a new one which means quite a bit more money. Wish I knew how to drop my engine and just put this thing on myself. I'd save a thousand bucks!
In the meantime I'm just watching the oil level. I backed the 911 back up on yellow ramps and went through a can of engine degreaser and brake cleener and wiped down every bit of oil I could see. On my way in to work- still smoked a little. i know that drip is dropping right on my right side exhaust cover and thus smoking off. Wish I could at least redirect the drip to the ground, at least it would not smoke any more.

[gtc]

does heat exchanger need to be removed to change engine oil cooler seals?

That said, if you have the time and space to do an engine drop, as well as the desire to get your hands really freaking dirty, I am sure there are some pelicans in your area that could assist you.
Waynes book and the Bentley manuals also do a good job of explaining how to drop the engine. Except for the actual lowering, it's pretty much a one person job.

Also, you can send out your old oil cooler for testing and cleaning in case you think the shop is trying to hose you by making you buy a new cooler.

[FinallyGotOne]

No I know my shop isn't trying to screw me. I Love my shop, they have saved me a laot of money and even have done things for me for no charge! It's just that decision to get new vs, saving a lot and buying used. I also wonder if there is a different soluition to that oil cooler? I also was thinking to run a thicker oil in there to prevent maybe a bit of the leaking so much. like a 5-30. would that be a good idea?

[Eagledriver]

You don't have to pull the engine to change the cooler. You only need to drain the oil, disconnect the oil line, pull the side engine tin, and pull to cooler shroud off the top. Then the cooler comes out by removing 3 nuts. Need 3 new seals (1 big, 2 small). Takes about 2 hours for an amature.

-Andy