When your 60 heat works well....

[Elbert]

Ok, so no answers, but a little different problem:

When I am driving around town, my temp gauge is nearly pegged (like the thermostat hasn't opened, and there is a hot spot in the engine water passage at the sender). Oddly, when this is happening both heaters blow cold. When I get on the highway and drive 4-5 minutes the temp gage drops to the center of the range, and the air blowing from both heaters comes up to normal, right away. Does the heater core only flow when the thermostat is open? Seems unusual, but is the only way I can explain the symptoms!

Thanks for your help!

Dan

If it were me...I would install an aftermarket temp gauge first. To verfiy the temps. Anytime the temp gauge is showing almost it's max hot value its time to stop and figure out what's going on. I would first replace the thermostat and gasket + o-ring. It sounds like your fan clutch may not be working correctly.

Radiator in good condition? Coolant is green and looks ok? Do you have a fullly functional fan shroud?

 

[dshock]

Everything on the truck is present and seems to be functional. It was a AZ truck, and I took it to Baja without any issue. Never getting this hot on the temp gage.

I am thinking that the thermostat and temp sender may be in different locations causing the sender to get very hot before the stat opens. Once open, it seems like the system regulates, very well.

I don't know. That is my hypothesis...now to figure out why the thermostat is staying so cool, or opening late...

Dan

 

[Elbert]

We'll there not much to look at in regard to troubleshooting a thermostat. If you even think its not working right you just replace it. If there are no other compoents in question as to their performance, that's where I would start. The thermostat is an independent mechanical device....it does not have any external controls. It would make good sense to start there 1st, by replacing the thermostat and assoicted gasket and o-ring.

Yes the thermostat and temp sender are at different locations on the engine, but both are in the cooling system. I've read where many people question the performance of the OEM temp gauge. I personally want to know in "numbers" what the temp of the vehicle is....not to comfortable with just hot and cold range.

There are no signs of oil in the coolant or coolant in the oil? Radiator is full of coolant? I would start with the thermostat as its the cheapest and most logical place to start.

No signs of sludge in the radiator or obviious signs of a radiator that needs replacement, no signs of coolant leaks around the water pump?

 

[Zack1978]

We'll there not much to look at in regard to troubleshooting a thermostat. If you even think its not working right you just replace it. If there are no other compoents in question as to their performance, that's where I would start. The thermostat is an independent mechanical device....it does not have any external controls. It would make good sense to start there 1st, by replacing the thermostat and assoicted gasket and o-ring.

Yes the thermostat and temp sender are at different locations on the engine, but both are in the cooling system. I've read where many people question the performance of the OEM temp gauge. I personally want to know in "numbers" what the temp of the vehicle is....not to comfortable with just hot and cold range.

There are no signs of oil in the coolant or coolant in the oil? Radiator is full of coolant? I would start with the thermostat as its the cheapest and most logical place to start.

No signs of sludge in the radiator or obviious signs of a radiator that needs replacement, no signs of coolant leaks around the water pump?

If there was oil in the coolant, what would that indicate?


Thanks,
Zack

 

[Elbert]

oil in the coolant is a classic sign of a blown head gasket. But on the LC it could also be from a leaking oil cooler. A compression test might be in order if yous suspect a head gasket issue. Some shops have a tester that will assist in head gasket failure analysis.

Anytime I suspect a coolant leak...I would have the system pressure tested (coolant system), which normally will show the leak.

 

[Zack1978]

oil in the coolant is a classic sign of a blown head gasket. But on the LC it could also be from a leaking oil cooler. A compression test might be in order if yous suspect a head gasket issue. Some shops have a tester that will assist in head gasket failure analysis.

Anytime I suspect a coolant leak...I would have the system pressure tested (coolant system), which normally will show the leak.

Hmmm........I noticed what looks like oily slime on the inside on the coolant overflow bottle, but in the radiator it looks fine. That is strange.


Zack