Cooling system curiousity

[prove_it]

I got my car running again and have been working on the tune. One thing I've noticed is that when I cold start the car the coolant will heat up to 225 then the fans come on and cool it off. Once the temp drops to 200 or so, it will never go past 210, even under load, NEVER. Only during a cold start will it hit 225. Hot starts everything will work perfect. The thermostat is two years old and is a stant brand. I might try an oem and see, but I thought I'd ask for some opinions first before making a mess. I'm running 50/50 blend with a bit of water wetter for coolant. Other than that the fans work fine.

Any input is appreciated.
Thank you!

 

[JSchleim18]

Kind of sounds like the coolant temperature switch isn't working on the top of the thermostat housing. Depending on what temperature t-stat you got, feel the upper coolant hose for hot water passing through it. If it's an OEM replacement, check around 195* F. Keep touching the hose before that to make sure it stays cool. If it gets hot at the 195-200 mark, then the t-stat is working OK.

The fans are turning on at 225* because the smaller a/c switch in the back of the t-stat housing is telling the car to turn the fans on. They turn on high. This is the emergency fan switch. I forget when they shut off though so when you're hot starting the car the temperature of the vehicle is still in the switch's operating temperature range.

 

[prove_it]

Your forgetting the part where it only happens once on a cold start only. Never runs above 210 even idling for 30 minutes with the hood shut won't do it. Only once every time I cold start the engine will it hit 225 then its good. Normal conditions after that. Thats the strange part.

I will check the switch just in case.