94 GMC 1500 4.3 v6 runs hot
Question:
does it have a tiny notch in the edge of the disc to let the air out from under it? or a small hole, or some path for air to exit? if air is trapped under it, it may never open – Hide quoted text — Show quoted text -> I replaced the thermostat 195 degree with the same. > It does not open up. The engine will go to 250 degrees. > The water pump is not leaking. Why won’t the thermostat open up??
Response:
> I replaced the thermostat 195 degree with the same. > It does not open up. The engine will go to 250 degrees. > The water pump is not leaking. Why won’t the thermostat open up??
Is it in backwards?
Response:
Several reasons come to mind right away: 1. Is it installed in the correct direction and is the system bled of air? 2. It may be stuck open or closed. Either could cause an overheating problem. 3. You may have a bad radiator cap. A cap that doesn’t hold proper pressure will cause your truck to overheat. For only a few bucks, replace the cap when replacing the thermostat. 4. Your water pump may not be turning. While the pully and shaft may be turning, the impellor may be stripped off the shaft. 5. Your radiator fins may be clogged up preventing air from flowing thru the radiator. Same for your A/C condensor and aux. tranny cooler (if you have either one). Both sit in front of the radiator. Bug screens, bras, certain fancy replacement grilles may also prevent enough air from flowing thru the radiator. 6. Not enough coolant, too much air in the system. 7. Your fan – specifically the thermostatic fan clutch – may not be engaging. If the fan clutch is out to lunch, the fan will not turn with enough power to force enough air thru the radiator to cool it off. Good luck – Jonathan — Acta Non Verba – Deeds Not Words Jonathan A. Race Lieutenant, EMS Supervisor Orange County (FL) Fire-Rescue Department – Hide quoted text — Show quoted text -> I replaced the thermostat 195 degree with the same. > It does not open up. The engine will go to 250 degrees. > The water pump is not leaking. Why won’t the thermostat open up??
Response:
Thanks for all of the advice. I replaced the thermostat, thinking that was the problem yet it acts the same. How do you get the air out of the system? With the thermostat removed the engine does not get above 120 Degree That tells me that the water pump is working. I installed the thermostat the same way the other one was place. The Spring down toward the block.
Response:
Could be a crap stat, new does not mean good. – Hide quoted text — Show quoted text -> Thanks for all of the advice. > I replaced the thermostat, thinking that was the problem yet it acts the > same. > How do you get the air out of the system? > With the thermostat removed the engine does not get above 120 Degree > That tells me that the water pump is working. I installed the thermostat > the same way the other one was place. The Spring down toward the block.
Response:
Whenever I install a new thermostat I always drill a 1/8 hole in the disc plate. This will let the air back up the top hose but doesn’t affect thermostat operation one way or the other. You also don’t have to wait for it to open and the coolant level to drop so you can finish filling the system completely. New vehicles have at least a part of the top hose higher than the top of the radiator making it hard to pass all the air out so the hole helps fill it that far and parking the car facing up hill or with the front wheels on a set of ramps helps too. — Mike ( Anti Spam Address ) "Opportunites are spawned from crisis" – Hide quoted text — Show quoted text -> Thanks for all of the advice. > I replaced the thermostat, thinking that was the problem yet it acts the > same. > How do you get the air out of the system? > With the thermostat removed the engine does not get above 120 Degree > That tells me that the water pump is working. I installed the thermostat > the same way the other one was place. The Spring down toward the block.
Response:
I drilled 2 small hole about 1/8" into the thermostat. No luck, except now it does not go into the red 260 is stays about 245 if my meter is correct. I also replaced the radiator cap it had 15 lbs the new unit is 16 lbs. I wonder if my sending that I replaced is working correctly? The unit I took out had only 1 wire. The unit I put in had 2 wires. I hooked the black wire to ground and the other up to the senor wire.
Response:
sounds like you have an ECM coolant temperature sensor there, instead of a – Hide quoted text — Show quoted text -> I drilled 2 small hole about 1/8" into the thermostat. No luck, except now > it does not go into the red 260 is stays about 245 if my meter is correct. > I also replaced the radiator cap it had 15 lbs the new unit is 16 lbs. > I wonder if my sending that I replaced is working correctly? > The unit I took out had only 1 wire. The unit I put in had 2 wires. I > hooked the black wire to ground and the other up to the senor wire.
Response:
There you go! Wrong sender. The engine was probably running at the correct temp all the time. Did you mention the sender in the original post? If you did I don’t recall it indicated a 2 wire one was put in place of a single wire one. Oh well, at least you found the cause. — Mike ( Anti Spam Address ) "Opportunites are spawned from crisis" – Hide quoted text — Show quoted text -> I drilled 2 small hole about 1/8" into the thermostat. No luck, except now > it does not go into the red 260 is stays about 245 if my meter is correct. > I also replaced the radiator cap it had 15 lbs the new unit is 16 lbs. > I wonder if my sending that I replaced is working correctly? > The unit I took out had only 1 wire. The unit I put in had 2 wires. I > hooked the black wire to ground and the other up to the senor wire.
Response:
Yes, It was the wrong sender. The guy at the parts store never asked me if I had gauges or not. They look the same except the other unit uses 2 wires.
Response:
I replaced the thermostat 195 degree with the same. It does not open up. The engine will go to 250 degrees. The water pump is not leaking. Why won’t the thermostat open up??
Response:
Is the spring down? – Hide quoted text — Show quoted text -> I replaced the thermostat 195 degree with the same. > It does not open up. The engine will go to 250 degrees. > The water pump is not leaking. Why won’t the thermostat open up??
