Help! 2UZ-FE Overheating on uphills only tried normal fixes

[duffdog]

So I just recently am experiencing an overheating problem. Cruising around in 105 degree temps with the AC on the truck does not overheat, even freeway speeds in high temps over 109 it is solid. Uphills causes the truck to slowly overheat after about 30 minutes of sustained climbing, and this is in 84 degree outside temps.

Anyone heard of this before? I changed the thermostat already and ordered a new radiator which should be coming soon. Is there any chance that it could be the water pump and if so, how would I test it? This just started happening after I drove the truck into the ocean 2 weeks ago, I'm not sure how to diagnose this one.

 

[gm350reratliff]

How far into the ocean did you go? My guess is that the fan clutch may be failing and/or the radiator may be a little clogged with debris.

 

[duffdog]

How far into the ocean did you go? My guess is that the fan clutch may be failing and/or the radiator may be a little clogged with debris.

A wave came over the headlights, so pretty far i guess. Also, i have electric fans on the radiator instead of a mechanical fan clutch. They have been working well for 2 years, and still work great around town. The problem only happens at freeway speeds where the electric fans never turn on.

 

[gm350reratliff]

A wave came over the headlights, so pretty far i guess. Also, i have electric fans on the radiator instead of a mechanical fan clutch. They have been working well for 2 years, and still work great around town. The problem only happens at freeway speeds where the electric fans never turn on.

Have you tried lowering the temp on the controller so the fans come on when you're on the freeway? Where is the temp probe placed? If it's one of those temp probes that you just stick in between the radiator fins, you may want to start there. I've had bad luck with those before and had to switch to a fan controller that actually looked at the antifreeze temp.

 

[duffdog]

Have you tried lowering the temp on the controller so the fans come on when you're on the freeway? Where is the temp probe placed? If it's one of those temp probes that you just stick in between the radiator fins, you may want to start there. I've had bad luck with those before and had to switch to a fan controller that actually looked at the antifreeze temp.

I thought that no electric fan system comes on over 60mph because the air moving through the engine is already going faster than the fan is capable of? Anyways, I actually have a redundant system that has both a temp probe in the fluid and another one on the radiator. Both are accurate and cause the fans to come on at the right time, but I can't see either system causing the fans to turn on when driving 70mph up a hill.

 

[RonJR]

I'm not a big believer in electric fans. There is just no way they can move the air that an engine driven fan can pull. It takes about 60 amps to provide one horsepower to the electric fan, and that's a fairly small fan. By contrast, the belt drive on the engine can easily provide 5 times that much power.

12 volt systems just aren't the right answer for providing significant mechanical power.

 

[duffdog]

I'm not a big believer in electric fans. There is just no way they can move the air that an engine driven fan can pull. It takes about 60 amps to provide one horsepower to the electric fan, and that's a fairly small fan. By contrast, the belt drive on the engine can easily provide 5 times that much power.

12 volt systems just aren't the right answer for providing significant mechanical power.

I kind of agree with you on that. My dual fans pull 70A when on and you can really feel them working, but somehow I don't think they are as strong as an 18 inch fan driven by the engine. But either way, the fan would not normally engage when driving on the freeway right? Am I wrong about that?