My engine keeps trying to overheat...

[compnerdansel]

Yes, i did a search but couldnt find a BJ with similar symptoms. Basic jist is every time im idling for a while the temp gauge starts to climb on me, or if im doing a long uphill pull. Its only started doing this now that the weather has warmed up, so its like the cooling system is just barely not able to handle the heat being generated. Its pretty much ok once im up to speed. I know this sounds like a bad water pump, but at 200k miles it stripped the teeth off the timing belt, so I put in a low milage engine from japan. I put in a new water pump and thermostat while I was at it, so i doubt those parts are failing when their only 4 months old. Sure the radiator has some bent fins, but about 90% are still straight, and the main fan is always on when i pop the hood to check, the AC fan kicks on to help, but never stays on for more than about 30 seconds. I put on a new 1.1 bar radiator cap, didnt help. I drained about a half gallon of coolant, poured in a bottle of water wetter, and refilled with just water to try and increase the thermal capacity but that didnt help much either. (and yes, i got all the bubbles out) Im out of ideas and was wondering if anyone else had this problem, because it sucks sitting in my car in 90 ° weather with the defrost blasting at full heat trying to keep the temp gauge below 3/4.

[irishkev90]

My BH did this like CRAZY last summer. Pretty much every time I drove the car. Fine in winter and doesn't do it as much this summer unless I'm really pushing the engine. I haven't bothered to look for a fix since this will soon become a winter/project car and I'll hopefully be pulling the engine to refresh it a bit.

Anyway, added some more water like you did and it didn't fix anything. Nothing blocking the radiator and fins look fine, I think the A/C condenser takes most of the road damage. Haven't replace thermostat or anything like that, and my water pump is original as far as I know, with almost 165,000 mile on the odometer, hehe.

Anyway, I'll be checking in on the thread to see if anything would me. But as for a solution, I got nothing. Sorry.

HTC Droid DNA

[1st Gen]

Is the thermostat correctly rated for this engine, or can you put a cooler one in it to help control heat build up.
You could put an extra fan in, maybe a front mount. (I have no idea what your bay looks like).
Is a hose kinked somewhere? Not enough to stop flow but enough to restrict it.
Do you have access to a temp gun? If the fan is shutting off before it's supposed to, then something is amiss in that circuit. I think my temp gun is about 30 degrees off some times but if I use it on a something with a know temp, I can somewhat calibrate it.
Maybe flush the system? IDK, that's all I can think of right now. Good luck.