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-   -   white smoke @ startup....blown turbo? (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/white-smoke-%40-startup-blown-turbo-779101/)

rotorypolo 08-13-08 11:24 AM

white smoke @ startup....blown turbo?
 
I always get a slight smoke at startup... but recently, the smoke is getting a bit more, it only smokes when the car sits over night and cool, but it will go away after 5-10 seconds. I believe my turbos are leaking oil, they are about 80K miles on them. what you guys think?

superjet3 08-13-08 11:39 AM

Does the smoke smell like oil? or is it sweet like coolent?

fendamonky 08-13-08 12:03 PM

I remember reading that a bit of white smoke at start-up is pretty much normal.

If the smoke persists for awhile, or there is an unusually large amount (I'm talkin' walk away coughing and waving your hand in front of your face), than I would become worried. Also, what color is the smoke?

Montego 08-13-08 12:06 PM

if it's white that's not oil. Oil = blue. black = fuel, white = coolant, or water/condensation.Keep an eye on it. Rotaries are known to smoke white upon start up. Condensation in the exhaust will smoke as it burns off.

If the problem gets worse, that is: hard cold starts with EXCESSIVE white smoke & engine not idleing right. Then after about a minute or so the problems just plain disapear, its usually a coolant seal problem. Which is of course bad news.

But don't worry just yet. When you have a seal issue it's obvious.

johnnymase 08-13-08 01:00 PM


Originally Posted by montego (Post 8462946)
if it's white that's not oil. Oil = blue. black = fuel, white = coolant, or water/condensation.Keep an eye on it. Rotaries are known to smoke white upon start up. Condensation in the exhaust will smoke as it burns off.

If the problem gets worse, that is: hard cold starts with EXCESSIVE white smoke & engine not idleing right. Then after about a minute or so the problems just plain disapear, its usually a coolant seal problem. Which is of course bad news.

But don't worry just yet. When you have a seal issue it's obvious.


Mine has the exact symptoms you just said, (hard cold starts with EXCESSIVE white smoke & engine not idleing right. Then after about a minute or so the problems just plain disappear) but it smells REAL strong of gas, and after that no problems at all. I've been told this is an electrical issue, and during warm up its rough when it holds a little above 1000 rpm, and during regular driving i do have some stumble a little above 1000 so i'm thinking that it just might be actually be electrical. Plus since it just goes away after about 2 minutes i've convinced myself there is no problem.:)

Plus i thought oil was black, but i am new to rotaries so im sure you are right.

Montego 08-13-08 04:10 PM

Well hope for the best, plan for the worst. :) I don’t know what’s up with the hesitation at 1K, nor the gas smell (check pulsation dampener, BTW a gas smell is no joke fix it!), but here’s some info.

Coolant/water burns white because it’s steam. What happens upon a cold start in an engine that suffers from coolant seal failure is as follows: It is hard to start because coolant has collected within the combustion chamber, within a few tries it fires up. Only to run like crap, it does so because the engine is essentially running on one rotor. Almost instantly there is a whole lot of smoke coming out of the tail pipe, this is due to the fact that the coolant that it is in the combustion chamber is burning off. Within a couple of minutes all of the coolant that was in the chamber burns off. So no longer is the car running on only one rotor and therefore the idle return as if nothing is wrong. Since the engine is nice and hot the coolant seal expands and prevents coolant from going into the combustion chamber. That is until you shut the car down and let it cool down.

Of course these issues start small and the severity increases over time. Keep an eye out for a lot of white smoke, unexplained coolant loss i.e. you find that you have to add coolant all of the time and yet you cant find the leak (actually the leak is your tailpipe ;), on more extreme case you find that your water temps skyrocket during WOT runs (that’s because exhaust gases are passing over to your coolant system causing the temps to rise).

Well good luck I hope that it is not an coolant seal failure. Also the champagne bubble test will just make you paranoid so don’t even bother.


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