Temp. Dillema

[ARTEMIS1759]

OK so I am back on leave from the military for 2 weeks and have 1994 GMC Yukon 4x4 2 door SLE with 5.7 and auto. Since I been gone in the last 6 months it won't heat up. It has a new radiator and a new thermostat was installed. I thought it could be the thermostat but not sure. I am just looking for ideas. There is no heat or luke warm heat and the temp guage reads right around 100. It runs fine but there is no heat. It seems to be loosing about 1 quart of coolant every 2 months. Anyone got ideas for me. I only got till the 17th. Thanks all.

[nubuilder]

I don't have any experience in the subject but:

 

1) check your heater core for leaks

2) check water pump bypass hoses for leaks

3) how old is the water pump (central location that feeds all other possible problem areas)

4) could your frost plugs be leaking (no idea, but it is 16 years old)

 

I'd start at the pump since it is basically the heart of the system and branch out from there.

 

One thing that I think was happening on my '98 was I don't think there was enough coolant in it so it would get just slightly past 210 before opening up. But since you have been adding, I don't think you should be at that extremely low of a level.

 

Is it possible you have a clog somewhere that isn't allowing coolant to flow past your thermostat (which I think is right where the temp sensor is) or to your heater core?

 

It shouldn't be the T-stat. Almost all T-stats fail in the shut position UNLESS you bought one of those fancy ones that fails in the open position. Also, you should still be getting heat in the cab even if the T-stat is stuck shut.

 

Again, I don't have any experience with this. Just brain-storming.

 

Good luck.