Bump

 

Id say use a mazda OEM thermostat. You can get one from rx7.com or mazdaformance.com as well as your local dealer. Im going to try changing the thermostat, may be that will solve my problem since it has never been changing in the life of my fd.
If it doesnt work im just going to send my car to Marvel for street port rebuilt.

 

fellas. Thank you so much. after a year of leaks through the overflow tank. I finally solved my problem. I changed my thermostat and it looked cooked, the gasket was issapearing and coming apart into pieces and it had expanded with the heat. Also one of the cooling lines that cools down the turbos literally broke into pieces while removing it. Problem solved!