how to diagnose smoke on start up?

[porsche83]

recently purchased a 83 sc that had the engine recently gone thru (tensioner upgrade,3.2 kit,complete rebuild maybe 40,000 miles ago .smokes alot on start up and no other time,

[911s55]

What's alot, and how long does it last?
Most of our cars have that symptom.

David

[James Brown]

mine does but it smells like burning gas, sometimes a lot not so much if I let the engine idle a few minutes before shutting it down. if it goes away soon after start, that's normal for a car with higher mileage. If it still smokes at normal operating temp and/or on hard acceleration, it might need new valve guides or P/C rings.

[Wavey]

Let it idle for 30-60 seconds before shutting down. You can watch the oil level gauge move up as the oil is pumped out of the crankcase and into the tank. You should get a lot less or no smoke on startup if you always do this.

[jevvy]

Check you plugs for an oily one, you might have a blocked injector or faulty spark on one cylinder making it run weak and oily.

[911st]

If it is cool where you are you can get a fair amount of steam from condensate and it can look like smoke.

It is normal for a pancake motor to puff a little smoke on start up which you might smell for a bit.

If you are blowing a lot of blue smoke, I would check the plugs as noted as you will be burning a lot of oil with acceleration and on throttle lift also.

[oliver88]

Check the oil level...most liklely too much oil. a little smokey start up is normal however.

[ahdoman]

I've even noticed a difference with oil type. My car will smoke a bit more on startup if I use synthetic. Regular Brad Penn and no smoke on start.

[Wavey]

Weird - exactly the opposite of my experience. Brad Penn smoked way more than M1 in my car.

[JJ 911SC]

Originally Posted by ahdoman

I've even noticed a difference with oil type. My car will smoke a bit more on startup if I use synthetic. Regular Brad Penn and no smoke on start.

When I got the car, 4 months ago, following the PO oil change with 20/50 synthetic, it use to leak like a sieve... but not much smoking on start-up.

I did the top up with Brad Pen and the leak stop but the White Smoke at start-up seem to have increase.

When it smoke there is also water drops coming out of the mufflers pipes kind of indicating that it's condensation from somewhere.

[RWebb]

smoke color?

how many days sitting when it smokes on startup?

[stlrj]

Originally Posted by porsche83

recently purchased a 83 sc that had the engine recently gone thru (tensioner upgrade,3.2 kit,complete rebuild maybe 40,000 miles ago .smokes alot on start up and no other time,

Was this a recent development or has it been doing this all along?

[James Brown]

wow water out the tailpipe, that sounds like a head gasket!! any antifreeze in that water??

[stlrj]

Does it smell like oil and linger in the air before dissipating? Condensation does not smell nor does it linger like oil.

[berettafan]

shoot a vid for us.

wavey that idle thing is pretty interesting, never heard that before. would this practice possibly cause the moving parts to be slower to get oil at startup?

[Wavey]

Originally Posted by berettafan

wavey that idle thing is pretty interesting, never heard that before. would this practice possibly cause the moving parts to be slower to get oil at startup?

I thought that was pretty much common knowledge but maybe not? It's worked like a charm for me. I doubt that there's any change at startup - it just gets the excess oil out of the crankcase so it cant sit in the bottom of the cylinders and seep past the rings overnight. I'm sure there's still oil everywhere it needs to be on startup. I use M1 so I don't worry too much about it with the synthetic anyway. On the rare occasion I'm in a hurry or I forget to let it idle, I'll get the normal startup smoke. But otherwise, VERY little or none.

But porsche83's issue sounds like normal condensation to me, especially if he's doing short trips. Or it could be a little condensation and a little oil if he's not using the idle method.

[mca]

If it is strictly white smoke, couldn't it be fuel?

I get this every so often on my fresh motor. Smells like sulfur and is white. Dissipates immediately.

[Tincanguy]

Originally Posted by Wavey

Let it idle for 30-60 seconds before shutting down. You can watch the oil level gauge move up as the oil is pumped out of the crankcase and into the tank. You should get a lot less or no smoke on startup if you always do this.

+1, Wavey! My 88 Targa never smokes on startup IF I let it idle for 30-60 seconds before shutdown. Although this may not work for very high mileage cars, it works perfectly for my 95K mile Carrera

[JJ 911SC]

Originally Posted by James Brown

wow water out the tailpipe, that sounds like a head gasket!! any antifreeze in that water??

Since its Air Cooled... lol

[JJ 911SC]

Originally Posted by stlrj

Does it smell like oil and linger in the air before dissipating? Condensation does not smell nor does it linger like oil.

No smell and it dissipate with a couple of feet pf the pipes...