Hi. My RX7 is having overpressure problems in coolant system. I've replaced the thermostat and water pump. The car has never overheated. I've tested the pressure and it's holding perfectly. I also did a CO2 test and it came back negative. When Im bledding, it have bubbles at idle but when i rev it it stops, after 10 minutes the buzzer starts and the top of the radiator is full of air. Im using lisle funnel. Thanks in advance

video: https://youtube.com/shorts/65j6gjYADBQ?si=-IqXD2Lek3_HZ0XW

 

Sounds like you need to keep bleeding it. With the clutch fan spinning its possible its not getting hot enough sitting at idle so you're not getting a proper bleed. If you're not seeing steam and a light boiling in the funnel then it's not hot enough.

 

Sounds like you still haven't fully bled the system.

Have you tried elevating the front of the car, with the lisle funnel? I'm guessing you have a pocket of air somewhere that's refusing to burp out.

 

I haven't tried that method. At first, I thought I had a broken coolant seal, but I removed the thermostat and I make a pressure and CO2 test. What I don't understand is why the top of the radiator fills with air when I'm bleeding the system. Thanks

 

I've read some posts on this forum with the same case as mine:

https://www.rx7club.com/2nd-generati...-958205/page2/

 

This is the coolant I used when I tested with various thermostats. It's a 10% coolant, boiling temp 230. Thanks

 

Could someone help me?Thanks!!!

 

2 of us already gave you recommendations. Have you followed up on them? What is your question?

 

I make the test without the thermostat, so I imagine it's not a temperature issue. Tomorrow I'm going to try elevate the front of the car and try to bleed the coolant. Could the problem be the coolant?Is only 10%coolant. I've also bought a new radiator. Thanks

 

Hi. After bleeding the coolant for 20 minutes with the car elevate on the passenger side, this is the result. What do you think? I'm making these tests without the thermostat. Video update