LUVTruck.com

i have a built motor and am having cooling system problems.....


during warm days the truck runs at 190-220+ (i think....just under over heat on the guage) and during cold days it doesn't get above 170....

i already changed the thermostat...i have a NEW radiator.... no leaks anywhere(that's a feat in it'self) new pump,new hoses all the way around

the only thing i can think of is that i have the heater control valve bypassed open. it leaked bad when i got the system to pressure.

HOW BOUT A LITTLE INPUT?

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What was the temperuture rating of the thermostat you replaced? I recall the rating should be 195. It should be stamped on the thermostat itself. If it is too low like 170 then on cold days it will open too early and motor will not get to the proper operating temperature. On hot days the early opening of the thermostat will only cause a longer warm up period, the cooling system should operate at its maximum efficiency and keep the engine operating around 195 - 210 degrees or so.

If the thermostat is stamped 195. Place the unit is a pot of water and slowly heat it on the stove when it starts to open measure the temp of the water it should really close the rating.

Hope this helps

i'm thinking that with the heater valve open all the time that the coolant is circulating too much at start up not letting it heat up all the way and when it's hot it's not cooling a good percentage of the flow(it makes my feet hot). i fi turn the heater on when it's hot it makes a huge difference in temp but just not enough.

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Hi,
I must say you are one of the very few who has an "over' cooling problem most of us struggle with a heating problem. Putting that aside, the radiator is the primary cooling for the engine, your heater core is a type of radiator of a smaller capacity but should only change the actual coolant temperature by a few degrees. The thermostat controls all coolant return flow back to radiator. During warmups, when the thermostat valve is closed the radiator is effectively non functioning. There is some circulation through the bypass hose, and through the heater, but nothing through the radiator. So an open heater flow valve will increase the warm up time since it still has a cooling path. With a 195 degree thermostat the valve will start to open aroung 180 or so, then wide open at 195. During "cold" days the operating temperature should be between 185~195, the operating range of the thermostat. If your running temperature is 170 then the thermostat is cooling(opening) too early. I think that a 170 operating temperature is below the recommended levels set by car manufactures.

Good luck fixing this problem.

my truck usually runs in the180-190 range. I was having problems whith it running at 210-220 so i whent to a 6lbs radiator cap and i just recycle the tossed coolant from my catch can once a week. I know that the 2.6L and 2.3L Troopers have had air buble problems and as the LUV is not much diferent than that Trooper (as far as the heater and cooling system goes anyway), this might be your problem. Try starting the truck and running it whith the radiator cap off. This should let any and all air out, also make shure that your coolant isnt up to the brim of the radiator, it should only bee enough to cover the top level of the radiator cores by a bit (maybe 1/2-3/4 of an inch above the cores). Well try this stuff and hopefully that fixes it!

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1980 LUV 4x4, going under re-construction...

i tried to get some air out but there was nothing in there.....i ran a compression check on the cyls and that came up clean.... i pressurized the cooling system and it held 22psi for 20 minuites before i let it out........i can't think what else it could be........?

i'll runit in the morning with a clamp on the heater hose and see if that helps for startup but i don't see a hot day coming anytime soon.

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double post.....previously triple post....

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