jet911

Looking for input - I had some work recently done on my 86 911. I have never had this issue before. When I started the car, it blew a bunch of smoke out (white). You could smell oil burning and after a few minutes, the cabin began filling with smoke. I brought this to the attention of the wrench who did the work. He did not know what would cause this, but stated that there must be some oil in the heat exchangers. He told me to take it for a run to heat up the car and the oil would burn off. Did so. Drove hard for 40 miles and had no more smoke. Got home let the car sit for about a half hour and started it again. It blew white smoke again and you could smell oil burning. Once again the cabin started filling with smoke. I do have one small oil leak that I know of, and it is on the left side and appears to be from the valve cover (this was part of the work I had them do, i.e., valve adjustment). I'm at a loss with Porsches and am getting to the point of possibly selling the car as it has not given me the joy they seem to give others. I've had nothing but issues since I purchased the car 2 1/2 years ago and $5k later in repairs. I always wanted a Pcar, saved for 3 years, looked and looked, found what I wanted, had a PPI done prior to purchasing the car - I was told it was in very good condition - however since then nothing but problems, frustration and a much thinner wallet. Does anyone have any idea why and how oil could get into the heat exchangers, when I only get a very small drip? Thanks in advance for any help and sorry about the long post!

Regards,
Jim
'86 911

Carreratek

Sounds like you need some good help.. What work was done to the car before the smoke. I have seen this happen before but usually on large jobs such as clutches, or engine r+r. let me know.

Mr Michael B

Jim,

Oil can easily drip off the valve cover area & right smack dab on the exchanger. At that point the oil gets real thin from the additional heat & can find its way INTO the cabin heat area of the exchanger via the round ports in the heat exchangers that are there for the exhaust pipes/tubing to pass through.

This is common.

Now what I think happened in your case is that while the wrench attempted his work in that area (valve adjust), he let a bit much overflow of oil out of the cam towers seep into the exchangers & through said ports. It takes very little oil to make the smoke you speak of, and it takes lots of time for that oil to burn off. I know what your going through, but as long as the oil drip has been fixed, this will pass.

If you want, you can disconnect the heat system rubber connection piece & flush out the exchanger with soapy water. That will steam clean the inside (once you drive) & help reduce the burn-off time.

jet911

Carreratek & Michael B.,
Thanks for the replies.

Carreratek - I had the transmission rebuild along with a new clutch, valve adjustment, and tune-up (new wires, plugs, rotor & dist. cap). The tranny rebuild has been nothing short of a total nightmare. I chose this wrench based on recommendations from PCA members, that he is a factory trained P mechanic and that he always has several P-cars in his shop. They have had the tranny/engine in and out five - that's right - five times over the last four months. I'm still not very happy with the job. There are noises now present that were not there before in the engine/transmission areas which are more pronounced when sitting in the car with the doors shut. Now when down shifting from 5th to 4th and 4th to 3rd, there are "clicking" type noises coming from, as best as I can tell, right under the shift stick. It never made those clicking noises before. Anyway, I'm about ready to just live with that part. The smoking problem never existed before. Even during the first four tranny/engine pulls, it did not smoke, only after this last removal and replacement of the engine/tranny.

The wrench has offered to keep monitoring the status for a year and has also offered to steam clean the exchangers.

Michael B. - Thanks for the info, I assumed that the heat exchangers were air/oil tight, not allowing contaminated air or oil to penetrate the system unless there were areas on the exchangers that had rusted and opened holes or cracks where oil could seep into the system. The car has only 78k miles on it. I inspected the exchangers and could find no rusted areas.

Advice?

Thanks again,
Jim
'86 911

Mr Michael B

Jim,

Naaa, they are not air tight. Sorry.

Oil gets in there pretty easy if you have a leak.

Sad you have so much trouble. 911's are great cars.

BoyT-911

Jet911,
The passenger side heat exchanger is notorious for this kind of problem. For smoke to get into the cabin, the source/oil must have accumulated from inside the heat exchanger.

Place some clean paper towels on top of your heat exchangers and allow to sit for several hours or overnight. You'll have some idea where oil drips are coming to your H.E. Just my $0.02.....

Ron_H

You did not say what year/model 911 you have, or I missed that.

At any rate, there was a time when living with oil leaks on the heat exchangers was part of the "mystique" Now the fix seems to be to install turbo rocker arm covers on the lower cam towers. They are reinforced and won't warp. A relatively inexpensive fix, in my opinion. Maybe that will do it. Look for some used, as new ones were about $85 last time I checked. <img src="graemlins/wave.gif" border="0" alt="[byebye]" />

Andreas Langhoff

Hi Jim,

the oil could come from a leaking rocker shaft. Oil usually goes through only when the engine is heated up. A fix could be putting the RSR seals shaft seals in.

Good luck

Andreas

cmoss

Sorry to hear about your problems. The need for a good mechanic is one thing that does not get mentioned enough. Try to find someone who works pretty much exclusively on P-cars.

Also note that these cars are--for the most part--old high performance vehicles. They will never (well almost) be as reliable as a Toyota (new or old!). These cars can become real money pits. $5K in a couple of years isn't all that bad... But then I've lost all sense of reason and perspective on this topic.

I think these cars are best thought of as hobbies.

gregg911

Don't get discouraged!!!

I had a persistant leak that seemed to migrate into my passenger side heat exchanger in my 80SC, and I wouldn't drive the car because after driving it for 10 or 15 minutes and parking it, some loser would walk up to me and say something like "your car is smoking, is it on fire or something?". It drove me nuts, the car just sat for months.

Having a slight case of OCD, very determined and being one to work on my own car, I cleaned the engine with a garden sprayer and some Castrol cleaner, drove it to dry it out. Then put blue paper towels all around on the ground and on top of the heat exchanger, I tracked the leak down to a drip in the valve cover and a slow leak at the seals around the oil return tubes. The drip at the valve cover would drip directly onto the heat exchanger and the leak at the seals would migrate around and eventually fall onto the heat exchangers.

I replaced the valve covers with turbo valve covers and gaskets ($100.00) and the oil return tubes were replaced with the collapsible type ($100.00). Once completed, the drips are gone and I'm happy again.

The cars are old, the seals are old. My knees and shoulders don't work as well as they used to either, but I deal with it. 911's are an obsession, sorry you have the disease, don't sell your car, deal with it.

Good Luck