So I drove from so-cal to WA state and back and everything seemed fine the whole time.
The next day or two I drove around for about an hour and parked and noticed the coolant in the expansion tank was boiling. At no point did the stock gauge deviate from the middle. Next thing I did was try to make sure air wasn't in the system and put in a different radiator cap. I let my girlfriend drive it for a while and she said it boiled a little bit once but otherwise behaved normally. Next I installed an inline coolant temperature sensor in the top radiator hose. I also replaced the clutch fan with a new AISIN unit. Today I drove to the store and the temperature on the new gauge reached about 220 and stabilized there. To me that seems too high since it's not even hot outside right now (~60f).
Backstory the rest of the cooling system had been replaced a year or two ago, it has an aluminum radiator with an OEM thermostat and all of the hoses replaced. I guess it's possible the new gauge is reading wrong, and I haven't driven it for long enough or in hot enough weather to see if it boils again.
The only thing I can think of that could have caused the issue was that I've put some of the radiator stop leak tablets in the system. The radiator had a pinhole leak at one point (possibly a mfg defect) and I've put a tablet in a few times to try to stop the leak (which it did). Now I'm wondering if it's blocked a passage in the block or in the radiator somehow. This may have been stupid in retrospect lol. I'm not really sure if there's a way to pinpoint whether or not that's the issue. They are the barr's tablets and they supposedly won't clog things up...
I'm considering throwing the radiator in the trash and putting in a new one, but I'm interested in hearing advice before I try it.
The next day or two I drove around for about an hour and parked and noticed the coolant in the expansion tank was boiling. At no point did the stock gauge deviate from the middle. Next thing I did was try to make sure air wasn't in the system and put in a different radiator cap. I let my girlfriend drive it for a while and she said it boiled a little bit once but otherwise behaved normally. Next I installed an inline coolant temperature sensor in the top radiator hose. I also replaced the clutch fan with a new AISIN unit. Today I drove to the store and the temperature on the new gauge reached about 220 and stabilized there. To me that seems too high since it's not even hot outside right now (~60f).
Backstory the rest of the cooling system had been replaced a year or two ago, it has an aluminum radiator with an OEM thermostat and all of the hoses replaced. I guess it's possible the new gauge is reading wrong, and I haven't driven it for long enough or in hot enough weather to see if it boils again.
The only thing I can think of that could have caused the issue was that I've put some of the radiator stop leak tablets in the system. The radiator had a pinhole leak at one point (possibly a mfg defect) and I've put a tablet in a few times to try to stop the leak (which it did). Now I'm wondering if it's blocked a passage in the block or in the radiator somehow. This may have been stupid in retrospect lol. I'm not really sure if there's a way to pinpoint whether or not that's the issue. They are the barr's tablets and they supposedly won't clog things up...
I'm considering throwing the radiator in the trash and putting in a new one, but I'm interested in hearing advice before I try it.