ginch

Hey guys,
I've owned my 964 for 6 months now. Absolutely love it. My question is about smoke at startup. My car 93 C2 with 48K, smokes for about 30 seconds when starting cold. It never smokes while driving or idling nor does it smoke when starting hot. I guess its not that big of a deal other than it being somewhat embarrasing. When I bought the car, I was told by several Porsche people that a little smoke at start up was normal for these cars. How does that explain those that don't smoke at startup however....abnormal?

Anyways, is this a big deal or should I just deal with it? Is the only fix for this condition a top end rebuild?

Thanks in advance for all replies!

Derek

demonfish

valve guides?

my 3.2 did, the 3.6 doesnt....

ginch

Sorry for my ignorance however does replacing the valve guides constitute a top end rebuild?
Derek

demonfish

to be honest, i wouldnt worry, maybe get a leakdown test if you want to check, that will tell you the wear on the engine...

my 3.2 is still going strong, and making good power.

ginch

Thanks man! Yeah, the car runs great and seems to have good power. I'm just curious how many of you have smokey 964's at cold startups!
Derek

Vifa

Have a smokey 964 at cold startup? I do!

Mine is a 964 Turbo as good as new because of the mileage is only 20.000 km. So I guess if mine smokes at startup now, it also did 16 years ago when it was complety new. Anyway, don't worry about this, it is normal. And I can promise you my car smokes a lot more than your car. So again, this is normal and don't worry about it!

Nine11

No smoke when starting cold or hot. I don't know if it's normal or came from the factory with this 'feature'.

74carreraturbo

Mine is a 91 with 84K and if I leave it for 2-3 weeks and start it up I get a tiny puff of smoke for 2-3 seconds and then it's gone... Never comes back unless i let the car sit for a really long period of time. Not sure why some would and some wouldnt ???


Rob

crg53

I used to get smoke on cold starts after extended no use, now what I do is, when I get home from a good run, let the car idle for a couple of minutes before you shot it down, gives you a chance to check the oil level, and no more smoke on cold starts. Give it a try.

911URGE

Ditto. Mine has 150k miles and only does this when sitting for 2-3 weeks.

ginch - Are you sure you dont have or had an oil overfill condition? Ive read that overfill conditions can lead to oil coating the intake system and then pooling into the cylinders causing the smoke at start. Of course oil can pool when sitting for long periods of time.

springer3

No smoke, even after sitting for long periods. 64 K miles.

ginch

Thanks for the replies fellas. The car has definately not been overfilled so unfortunately thats not the issue. I guess maybe the Valve guides are worn. Seems premature though doesn't it on a 48K mile car? Also, as asked before, does changing the vavle guides require a full top end rebuild?
Derek

altarchsa

+1 Ilko on valve guides, or seals

With so few miles, might the car have sat for long periods when the O.E. composite valve seal material could have dried out and shrunk?

Either valve giude or seal replacement = top end rebuild. At least top end diassembly/reassembly, which common sense turns into a rebuild. "Gotta take it apart to get to it", although I've heard of some Gerry-rigged schemes where air pressure in the cylinder is used to hold the valve against the seat while the spring is removed for a seal-only replacement. However, if you've got a problem, I think you'll want to get in there to evaluate the situation.

Only reason I would be concerned is that, from what I understand, valves are cooled by their contact with the guides, which dissipates heat through the head. Worn guides can result in overheating of the valve stems and failure. I had a valve break and it is not pretty. I tried to upload the phot of the destroyed cylinder and head, with the valve head jammed edgeways into the valve port, but couldn't get it to work.

I think it is possible, from an experienced mechanic feeling the play between the valve and guide by rocking the valve back and forth, to estimate the wear. I would recommend a valve adjustment with a request that the mechanic check the guides in this manner, if your mechanic agrees to this test. I think it is possible??? to check this with the rocker foot backed off and the valve springs loaded.

Hope I'm not making too much of this.

Good luck.

altarchsa

Sorry, that was demonfish's reply, not Ilko's, that I quoted.