Questions and Answers
Smoking RX-7
Q. Hello Vincent, I hope you can advise me. I bought an 1987 RX-7 non turbo a year ago, and put 9,000 miles on it. About four months ago, blue white smoke started coming out of the exhaust if I tried to drive without first warming up the car (I live in southern California, by the way, doesn't get that cold).
We check the oil regularly, but nonetheless experienced one abrupt drop in oil pressure that triggered an alarm about two months ago. There was a lot of smoke at that time. We put in several quarts of oil, and have watched it carefully since. It has not used up more oil than usual since, but gas mileage had dropped and it continued until this morning to produce the blue white smoke when it would hit about 3,000 rpms in warming up, and again, would stop producing the smoke after four or five minutes of idling. The engine also sounds unbalanced until it is warmed up.
Today I took it to a shop run by a man who claimed to have three RX-7s. I explained the above to one of his mechanics. Subsequently the owner called me to tell me that in his opinion the engine was shot and I would need to either buy another engine or junk it. I told him I didn't want to do either, and he suggested an oil additive he said would reduce the smoke and maybe get me another year. However, when I went to pick up the car and started it up, massive amounts of that blue white smoke came out and did not stop.
The mechanic who was there at the time, who was neither the first guy nor the owner, said that they had started it up, and that it had produced similar clouds of smoke for them that likewise did not stop. I told him that it hadn't done that in the morning, or for the last month, and he had no explanation. Then a fourth guy actually suggested I consider buying a car they had on the lot, at which point I began to believe they had tampered with the car.
I love the car. What do you think is wrong with it? Is there any hope?
Thanks very much,
ChrisA. That has a 1.3 liter rotary engine. A nice engine, but it had it's problems.
The biggest problem was with the Rotor Apex Seal (part number 7). This Apex Seal is the equivalent to the rings in a standard engine. It was pushed against the combustion chamber wall by a Rotor Apex Seal Spring (part number 6). These had a tendency to wear out rather quickly unless the engine was maintained religiously.
When they wore out, or the spring got too weak to hold the seal tightly, they started to smoke. The only way to fix it is to replace the Apex Seals.
It is also possible the rotor, the equivalent to the pistons in a standard engine, end seals (part number 5) may also be worn and allowing oil to enter the engine.
Unfortunately the answer in either case is an engine rebuild. As for them possibly tampering with the engine, if they put the additive they suggested in the oil, that could have very well opened the can of worms. It has been my experience that synthetic oils and oil additives do way more harm than good in a rotary engine.
Additional Information provided courtesy of ALLDATA
