Two possibilities here imho. One, you have weak oil seals. When the engine is stopped, oil will eventually leak past the seals into the rotor chambers, and then will need to be burned off. This smoke usually tends to be gray, sometimes bluish. Not a big problem, just may need to change/clean plugs more often.
Two, you have water seal problems. After the engine sits for a while, water will leak past the seals into the motor. If this is the case, you should be losing water with no apparent leaks anywhere. This is a bad one, only sure cure is an engine rebuild. Some people have been successful with stop leak. Somewhere there is a web site that talks about the stop leak treatment, but I don't remember where. Some help here, please?

Irv, Keith's dad

 

I've got what I believe to be a similar problem. I lose coolant every time the car is started, people say they can smell coolant in the smoke that comes out for roughly 30 secs after the car is started, and it also starts hard, like one rotor isn't running until I kick the revs up to 5 or so for a sec and it smooths out.

What we've been able to hypothesize is that somehow coolant is pooling in one rotor housing (a cracked seal or gasket somewhere?) and is having to be burned off when the engine is started.

This always creates a situation where there is just enough coolant liquid missing that the "add coolant" light&buzzer go off about 3/4 of the time the car is running, sometimes a little less, but no less than 1/3rd of the time. The temp USUALLY stays within normal specs (under ~1/4 of possible), but has been all the way to the top hot mark at least once when the heater hose tore itself apart. We prevented the engine from dying by not turning it off when it was that hot. We cooled it down while it was running and it seems to still work nicely.

Other than the coolant missing/burning (and thus buzzer&light) problem, there are no other drivability issues. I keep reading about other people's problems with their cars, and I think to myself how fortunate I am to just have this little (possibly fatal) problem...

Any ideas how coolant could get into the rotor housings, and what I can do to fix it?

Thanks...

 

I am in a similar situation, bought an 89 for a driver and it puts out white smoke on startup for a little bit. If you havn't allready do a search for "white smoke" and collect some more info. It seems to me like everyone has a different opinion on this.

There are a few things you can do to see how serious it may be.
First just watch the coolant resevoir to see if/how much the level goes down. You can also check for air bubbles coming up through the radiator. Take the radiator fill cap off and watch for bubbles after you start the car and it heats up. Vary the rpm with the throttle linkage and see if that prompts it also.

My car smokes kinda bad (white smoke) after it has been sitting for a few days, but the coolant level doesn't seem to go down and I haven't seen it bubble up at all, even when hot and reving it. Wierd thing about mine is that is won't smoke until the car is up to normal temerature, then it burns it off and is fine.

If you aren't loosing coolant (and your sure it's "coolant" smoke -white) then your best bet for now would probably be to live with it, let it warm up in your drive way and get it's smoking over with if it bothers you. When I run mine every day it doesn't smoke at all.

You didn't mention how often it smokes, every day or just after it sits?

Hey Irv, if you check this thread again let me know what you think about my car not smoking until it's warmed up. Made me wonder if it was connected to the thermostat opening up or something. Someone suggested it could be the bac valve?

 

Dave777,
If you are not losing coolant, my guess would be that it is not a coolant problem, but a condensate problem. You may have a spot somewhere in your exhaust system where condensate collects, based on your particular exhaust, and it takes a while to heat up enough to evaporate it. Nothing to worry about, IMO. You may find it eventually, if you don't have a stainless steel exhaust it will be the spot that is the first rust through.

Irv, Keith's dad

 

But in my car I *am* losing coolant. I check the level in the radiator each time before I go anywhere (of course I let the car cool down before checking so nothing evaporates away when I remove the radiator cap)... It only really smokes for the first 30 seconds if even that long, and not very much. But anyway, shortly after actually driving, the temp starts creeping up past where I think it should be (ie, it goes past half) and I have to do what I have dubbed "the thing", a processes I crafted the first time this new engine overheated (the engine is new to the car, not actually new, has ~90K on it) which basically is designed to cool the engine back to safe operating temps while it is running. Cooling it by turning it off while it is really hot is what killed my original engine.

With a towel folded over several layers thick, I loosen the radiator cap (while the car is idling), let it vent steam, etc... Then I remove it completely after most of the violent steam is gone, and run cold water from the hose into the radiator to replace the coolant that just evaporated when I opened the cap, to cool the coolant going into the engine, and to keep fluid in the system as having an unpressurized coolant system causes the coolant in the radiator to boil out the top. Once the temp gauge in the car reads ~1/8th or so for at least a minute, I'll turn off the car completely and let it cool itself from there.

This used to be enough. I used to be able to simply make sure that the fluid was topped off before I drove anywhere and then to watch the temp gauge carefully while I was driving. But lately the temps get up high before I really get going and even before the add coolant light comes on telling me that enough coolant has been lost that the coolant system couldn't cool effectively even if everything else was working correctly (which I don't believe it is)

I suspect a couple things. I suspect that the engine is losing coolant because it burns coolant. Hailers sent me a link to a mazdatrix.com page that explains how the coolant seals get cracked and the housings get cracked and deformed. I think I probably have at least a cracked seal...

I also believe that potentially the coolant mixture as a result of doing all this operation with water instead of recon or straight antifreeze to create a good mix is causing the boiling point of the coolant to be closer to that of water (lower) instead of high like antifreeze, which as I understand it, would make the fluid that does exist less likely to cool effectively.

My problem may simply be that the engine, once up to healthy temps, is hot enough to boil the mostly water mixture I have running through the lines, and it boils it away until not enough is left to effectively cool the engine.

I also believe my fan's clutch is worn out as I can't seem to make it blow beyond 1500rpm, but that's another story.

I have an autocross race coming up on the 16th, any suggestions or comments?