Introduction and question about my RX7
 

Hi my name is Ray Dogg and I'm a 31 year old grad student who recently purchased a used 1991 Mazda RX7 convertible from Craigslist. I bought the car for $3000 because it looked like it was in great condition and it only had 84,000 miles. The owner of the car was an actual mechanic who specilaizes in rotary engines.

But my question which is somewhat disconserting is that the day after i bought the car when i started the car the RPMs where like at 5,000 for like 25 seconds and white smoke was coming out of the exhaust. After the 20 seconds the RPMS would go down and the car quiets down. Is this a cause of concern? Also, the third day the car started making this alarm sound where the indicator dash stated to refill the coolant. I immediately made it to Autozone and filled the coolant. I added coolant again later. I am somewhat worried that maybe it has a broken head gasket....can anyone let me know if i should be worried?

Cold starts are supposed to bring the idle speed up to 3,000 RPM for 17 seconds, then fall to 1500 RPM. As it warms, it will settle at 750 RPM. If it jumps all the way up to 5,000 RPM, the throttle cable may be sticking, the throttle stop could have been messed with, or ECU related problems may be occurring. White smoke would be coolant burning, but if it's grayish, that would be oil. A little bit of oil smoke if you're reving it way up on a cold start can be normal. The oil control rings in the engine wear with time.

Download the factory service manual for the car (D/L links in the tech section FAQ), or get a Haynes manual. You should bleed any air out of the coolant system to prevent the low coolant buzzer going off. Of course, if you have a coolant leak, that will need to be addressed first. There is no such thing as a rotary with a head gasket. There are no heads. The rotary equivalent would be the coolant seals around the combustion chambers.

Welcome to rotary.. Land of no pistons..heads or pistons... I had a coolant problem like blowing white smoke to I was able to patch the the problem using sodium silicate.. Water glass.. I flushed the coolant system extensivly with radiator flush.. The I poured one bottle of water glass into coolant via the thermostat housing WITH NO THERMOSTAT.. Filled the rest with water.. Ran the motor til warm... the water glass seeps into hot spots and fills cracks with a glass like substace.. Let sit with the water glass / water for a week I drove the car lightly and idled it every day for 30 minutes... my car is fine now.. I shift at 8 k no problems.. Like I said its a patch no a permanent fix..