Just recently picked up my FD RX7 and I'm having an issue with the water temps. On idle the water temps are at 95 celsius while it is very cold outside. When I'm doing normal driving temps get up to 111 celsius. Highest I've seen it reach was 121. Coolant temps stay normal. Any suggestion on what it could be? I drove the car aggressively one night and water temps got to 118 celsius and it was a cold night 35 Fahrenheit. Is this normal or are the water temps supposed to be lower?

 

definitely running hot.

what mods do you have?

 

all it has is a catch can system and an hks v-mount kit.

 

Still have the air pump? You sure the cooling system is bled properly? Fans spinning the correct direction?

 

I will double check everything tomorrow morning and update

 

what coolant do u use ? any update ?

 

G05 valvoline coolant. I haven’t been able to check because its been raining this whole week. Waiting for a clear day.

 

Your 111 Celsius = 231 Fahrenheit just for reference.

In my drift t2 fc, I normally have temps around 190 Fahrenheit. After a few laps of WOT, I’ll let it cool down once I get around 205 fahrenheit.

You’re pushing the limits. Definitely should verify if the sensor is correct.

Even if the “average” coolant temp is 111 degrees, there could be boiling coolant on the hottest parts of the engine, the coolant jacket surface of the housings and irons.

I know that a fc needs an under tray or fc guys have issues with higher coolant temps, especially while at freeway speeds when the clutch fan is not working.

 

yeah I thought the temps were pretty irregular. I ordered a new thermostat thinking maybe that was the problem. But I’ll look into ordering a new water temp sensor.

 

sorry for the delayed response. I put new coolant in and bled the system. On a 90 fahrenheit day car idles at 97-100 celsius water temps. I still think this too high. I also verified that the car has the air pump and fans are spinning the correct way. Is this still too high? Anything else I can try? I’m still waiting to receive the new thermostat. Any suggestions?

 

Yes temps still seem too high. Are you able to control your efans? Figured there’s a chance you’re using a power fc and can lower their activation temperature.

im using Ford Taurus efans on my fc and if I leave them on constantly, the coolant temps won’t go past 160 Fahrenheit, 70C while idling and even while cruising up to and around 50 mph.

On the drift track I run them constantly and I can stay on track much longer than my friends, reaching normal operating temp of 180 F, and I start doing cool down laps at 205F but I still have head room to run hotter if I wanted to.

I normally have efans not on full constantly, and can have idling and driving temps right on 180-185F.

Install the new thermostat and go from there.

 

Just for testing purposes..... remove the thermostat. Leave the gasket in but remove the thermostat and see what the temps do

 

I discovered the issue. I removed the old thermostat and found part of the the seal melted into the thermostat so it wasn’t opening up. I replaced the thermostat and its now running perfect.

 

Good to hear. Glad you didn’t ignore it.