#EngineSwap : I think my thermostat is bad

[fiatmonkey]

I have noticed the temp in the k20 can drop 3-5 degrees in less than a minute AND the car appeared to overheat last night - temp soared to 215 before I could shut-down and park it. Oddly the heater seemed to pump out hot air the entire time. I am not totally surprised about that IF the problem was a blocked line to or from the radiator since the heater core bypasses the thermostat completely. Here is a crude diagram:

The one thing I noticed was the over flow tank was low but it filled up quick and never drained out at all.

Took the car out today and it seemed fine, fan came on like it usually does, etc. Again, it did do the sudden drop in temp again. It NEVER increases fast however, the exception being it could go up a tick or two when I get on it and engage the VTEC.

So I wonder if I should investigate the thermo. I am using an external Lancia thermo with the 3 ports (1 from waterpump, small return/bypass and one to the radiator). Sucks cuz it is the external type where the thermostat itself can not be replaced, but the whole unit needs to...

 

[Pete Whitstone]

Drop in coolant level

plus a sudden random spike in temps would mean air in the cooling system to me. There might be other causes as well, but that's the first thing I'd check for. What radiator are you running and what are your check-for-air/bleed options?

Pete

 

[fiatmonkey]

plus a sudden random spike in temps would mean air in the cooling system to me. There might be other causes as well, but that's the first thing I'd check for. What radiator are you running and what are your check-for-air/bleed options?

Pete

Hi Pete,

I ran the custom aluminum radiator from vicks, not the texas heat version, but the original racing version http://www.vickauto.com/newstore/index.php?main_page=product_info&cPath=5_7_54&products_id=3385

Not crazy about where they put dang bleed screw, but you can get to it. it is the only bleed location. I considered putting something on the custom coolant manifold on mine as well.

 

[Tas]

Hi Tim
you seem to be having a lot of fun with your cooling system,you may have to jump over to the K-Tuned stat that no one here likes:hmm:

 

[Tas]

Jokes aside,you added coolant notice any leaks,maybe do a pressure test to see if leaking any were

 

[fiatmonkey]

Jokes aside,you added coolant notice any leaks,maybe do a pressure test to see if leaking any were

Ultimately - I think the thermostat I am using is a bad idea and using the k-tuned might be the best.

I did find a leaking hose connector BTW last night. I haven't driven the car more than few drives around the block and it seems fine. I will monkey with it tonight and see how it does...