Since the summer temps. over here reached 110+*F, I've been finding that the engine runs hotter (the gauge needle on the L of NORMAL or ~222*F) when I'm driving on the highway with the AC switched on. If I switch the AC off (uncomfortable in this heat), the temp. gauge drops back to the M or NORMAL (an acceptable 208*F). In slow traffic, the gauge doesn't go higher than 208*F and the low speed fan works fine.
The cooling system is stock except for the t'stat being removed 3 months ago (it was stuck part-closed). The radiator cap is a new 16psi unit and it holds pressure fine. There's no coolant loss that I can detect. I flushed the system a while back and even left it for a couple of days with a 50/50 mixture of water/vinegar to clear it out. I then refilled it with a 30/70 mixture of coolant/water. The drivebelt is brand new and is properly tensioned.
I'm trying to put my finger on where the problem might lie. The symptoms were present even before I installed the ASP crank pulley and this made no difference. The AC blows cool air and works very nicely so I hate to switch it off to cool the engine down, but I'd rather sweat like a hog than damage the engine.
There are two likely possibilities that I can think of for the engine running hot. The most likely, I think, is that the stock radiator isn't man enough for the job. The other possibility may be the high speed fan not working but surely that wouldn't matter because there should be sufficient airflow into the radiator at highway speeds.
Can anyone offer any ideas? I hope HISSIN50 chimes in 'cause I know he's the cooling/electrical system expert here.
The cooling system is stock except for the t'stat being removed 3 months ago (it was stuck part-closed). The radiator cap is a new 16psi unit and it holds pressure fine. There's no coolant loss that I can detect. I flushed the system a while back and even left it for a couple of days with a 50/50 mixture of water/vinegar to clear it out. I then refilled it with a 30/70 mixture of coolant/water. The drivebelt is brand new and is properly tensioned.
I'm trying to put my finger on where the problem might lie. The symptoms were present even before I installed the ASP crank pulley and this made no difference. The AC blows cool air and works very nicely so I hate to switch it off to cool the engine down, but I'd rather sweat like a hog than damage the engine.
There are two likely possibilities that I can think of for the engine running hot. The most likely, I think, is that the stock radiator isn't man enough for the job. The other possibility may be the high speed fan not working but surely that wouldn't matter because there should be sufficient airflow into the radiator at highway speeds.
Can anyone offer any ideas? I hope HISSIN50 chimes in 'cause I know he's the cooling/electrical system expert here.