help with cooling problem
#1
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My buddy swapped in a lq4 drivetrain into a 79 full size pu. Everything works fine and the pullies are set identical to his 05 silverado with the same drivetrain, but the coolant isn't circulating. The t-stat is opening and is brand new. What could be causing the overheating? the only code his computer throws is the one for overheating, no other codes.
#2
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Could be a air pocket in the system, take step to purge the air out of the system.
Fill the system from the top radiator hose (disconnect it from the radiator) and then reconnect the hose and then top off.
Hold the engine at about 2000-2500 for a 20-30 sec to purge the system of air. Top off again and repeat a few times to get all of the air out.
Are you sure the T-stat is not binding in the housing and that it is opening at the right temp and that the fans come on at the correct time if your using electrical fans.
Fill the system from the top radiator hose (disconnect it from the radiator) and then reconnect the hose and then top off.
Hold the engine at about 2000-2500 for a 20-30 sec to purge the system of air. Top off again and repeat a few times to get all of the air out.
Are you sure the T-stat is not binding in the housing and that it is opening at the right temp and that the fans come on at the correct time if your using electrical fans.
#4
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Unbolt and remove one of the steam vent caps on the front top of the engine as you fill it. That gets the air out.
Also are you sure it is overheating and not just a bad sensor/shorted sensing wire? Did you check it with a second sensor or observe other signs of overheating beside the code?
Lasst thing, are the heater hoses hooked up? I hve heard LS motors circulate water through the heater loop while T stat is closed. Make sure there is a path their.
Also are you sure it is overheating and not just a bad sensor/shorted sensing wire? Did you check it with a second sensor or observe other signs of overheating beside the code?
Lasst thing, are the heater hoses hooked up? I hve heard LS motors circulate water through the heater loop while T stat is closed. Make sure there is a path their.
#5
11 Second Club
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Could be a air pocket in the system, take step to purge the air out of the system.
Fill the system from the top radiator hose (disconnect it from the radiator) and then reconnect the hose and then top off.
Hold the engine at about 2000-2500 for a 20-30 sec to purge the system of air. Top off again and repeat a few times to get all of the air out.
Are you sure the T-stat is not binding in the housing and that it is opening at the right temp and that the fans come on at the correct time if your using electrical fans.
Fill the system from the top radiator hose (disconnect it from the radiator) and then reconnect the hose and then top off.
Hold the engine at about 2000-2500 for a 20-30 sec to purge the system of air. Top off again and repeat a few times to get all of the air out.
Are you sure the T-stat is not binding in the housing and that it is opening at the right temp and that the fans come on at the correct time if your using electrical fans.
From this post, I'm guessing that the coolant is circulated inside the block, and then through the bottom hose when the tstat opens and then pushes the cool water through the top hose and repeats the process?
#6
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I had the exact same thing happen in a 97 blazer last week. Turned out it had a large air pocket in it that only worked it's self loose when the engine warmed up. Real wierd because the truck sat allnight after we put it together adn in the morning it looked full. We ended up putting almost another gallon in that "full"radiator.
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