Hey every1. I need a bit of help with my jimmy. It started overheating a couple of days ago. Got it home and replaced the thermostat. Didnt solve it unfortunately. I then took it to a shop that told me there was no coolant in the radiator even tho the reservoir was full. I was also told i'd need a water pump. I thanked them with an hour worth of labor and took my truck home. I then replaced the pump. Still overheats. Odd thing is the radiator cap and top hose are all warm to the touch. And so is the upper intake manifold. Yesterday, i could drive it a few miles b4 it overheats. Since changing the pump this morning, it couldnt make it 1mile b4 the needle got to red. Pls help. What am i to change next? There r only so many parts to the cooling system.
95 jimmy odd overheating problem
- Thread starter BAD SVT
- Start date
Is the radiator cap good? Is the hose from overflow reservoir to radiator good (This is the first place you should look)? And did you squeeze the upper and lower radiator hoses during fill up and engine warm up, after you changed the water pump? That will help get the air pockets out of the cooling system.
Well, actually the skinny hose from the reservoir does in fact look and feel old and cracked. I didnt think a worn hose could cause the problems i'm experiencing. I imagine it'd run a bit hot, yes, but not overheat. Am i wrong in assuming that? The cap is good i think. It tightens fine.
And just to add; When i pulled my truck into the gas station when the needle got to red, i felt the cap & hoses. All warm to the touch. To be sure i opened the rad cap and it looked full. And of course the coolant was warm also.
EDIT- Its got 240k miles on it.
EDIT- Its got 240k miles on it.
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Well, it looks like i underestimated the fact that when u empty & seal up a cooling system, air pockets form, & the engine has to cool down b4 topping it off. I just went back to the truck and opened the rad rank. TOTALLY EMPTY. The coolant i put in it after replacing the pump wasnt enough by a long shot. I opened the reservoir and saw that was full. So i got worried. Nevertheless, i pressed on the large top & bottom radiator hose like was suggested, and i quickly looked in the reservoire again. All the coolant was sucked right out
! Wow. I will never ever underestimate the value of warming up a car, leting all the air pockets out, and letting it cool down b4 topping off again. Lesson learned. Thx bro. U're the same guy who helped me with my last issue. U're a good luck charm
! Wow. I will never ever underestimate the value of warming up a car, leting all the air pockets out, and letting it cool down b4 topping off again. Lesson learned. Thx bro. U're the same guy who helped me with my last issue. U're a good luck charmThanks for the kind words, you did all the work. Now, the radiator overflow tank and its connecting hose are very important. Now a days engine run at high operating temperatures. The radiator fluid expands out during warm up and contracts when cooled. We're talking a fair amount of fluid here, maybe a pint ( if I had to guess) each warm up. Without a functioning overflow reservoir, the system will pump out engine coolant and then suck air in. The over flow system ensures only coolant, not air returns to radiator.
OK, you won't be able to feel a faulty radiator cap. It's designed to keep the cooling system at a specified pressure. If pressure is too low, fluid will boil out prematurely and won't allow the engine to operate at the designed working temperature. The radiator cap is often overlooked. Some people replace it every 1 to 2 yrs. For me, every 3 to 4 yrs.
Hope this solves your issues. If not, you will have ruled out the inexpensive fixes
OK, you won't be able to feel a faulty radiator cap. It's designed to keep the cooling system at a specified pressure. If pressure is too low, fluid will boil out prematurely and won't allow the engine to operate at the designed working temperature. The radiator cap is often overlooked. Some people replace it every 1 to 2 yrs. For me, every 3 to 4 yrs.
Hope this solves your issues. If not, you will have ruled out the inexpensive fixes
Thx man. I believe it's solved. It overheated after 1 mile of driving this morning. After letting the engine cool down and topping the coolant off, i've put about 3 miles on it and is not overheating. Needle is @ half. I'll put more miles on it and see if it stays that way. If it does, i'm golden. Thx again.
I was looking at this thread again, and it doesnt look like i was clear as to what solved the problem. So here's clarification: It was in fact the water pump that solved the issue. I just happened to also not let air pockets out properly.