OK here is the story, car is a 88 GXL with 99,900 miles. Did searches, ran all tests, here is what I get. Day one: Coolant buzzer goes on, so I fill her up, and is fine. Next day same thing, so I check for leaks, check caps, and nothing wet. I do this each time, (only drive her like once maybe twice a week) now finally one time I see where I am loosing, Its out of the overflow tank. So I do some searching and do some tests. Pull the plugs and crank the engine, no coolant here. Not much smoke out of the tails except the usual you get in cold weather. Did the bleeding with the bleeder plug, always full. But when I go next time to start her up when cold again add coolant comes on, but no major smoke, just the usual. When I go somewhere and come out like a few hours later, I now get the hard start and a little more smoke then usuall, still not much, and after a sniff test I do get a faint smell of gas in the overflow tank. So what i need to know is, is it possible that my coolant seals are going bad, or something else. Is it possible that coolant is not getting in the engine(tests show this to be so), but air and gas are getting in the coolant through coolant seals(tests show this to be so). Basically can the seals start to go and only allowing a one way passage, or is there something I am missing here. Also to add I did the geysur test too, no geysurs here. Very mind boggling. Please help I need this car for a few more months till my other 7 is finished. NOTE (not same problem)

 

You didn't run all tests. You didn't run a coolant compression test.

At first I would have told you that it sounds like you got a shitty seal on the rad cap. But with a gas smell in the coolant, fear the worst. Run the coolant compression test with an appropriate tester. If you find a leak, your lucky, if you don't, and the PSI on the tester starts to drop, rebuild time.

 

I'm having the same problem w/ my 88 RX7 conv. I also notice that the temp wil go up and down, when I shut the car down coolant will come out of the over flow. Any other options other than a rebuild ?

 

From the FAQ:

I think my engine has been overheated. How can I check to see if the coolant seals are good?
Fill coolant system ALL THE WAY UP (engine cold). Make sure that the fluid level is as high as you can get it. Leave the filler cap off. Remove the EGI fuse. Crank the motor (it should not start). If you get a LARGE amount of coolant coming out of the coolant fill, its safe to assume your coolant seals are blown. Also, a good indication is a fuel/exhaust smell in the coolant.

 

Coolant seals=rebuild