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Old 07-27-2016, 10:48 PM   #1
Bulldog88
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Can't figure out why my truck is running hot

Can't figure out what's wrong, I replaced, The water pump, thermostat, radiator, fan clutch and gets hot in about 10 minutes from a cold start, oil is not milky but just wondering if it's possible I have a blown head gasket
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Old 07-27-2016, 11:06 PM   #2
ls1nova71
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Re: Can't figure out why my truck is running hot

Are you sure it's full of coolant? Did you fill the engine through the top radiator hose? If you just put coolant in the radiator, it will not go into the engine and therefore not get to the back side of the thermostat so it won't open.
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Old 07-27-2016, 11:18 PM   #3
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Re: Can't figure out why my truck is running hot

Quote:
Originally Posted by ls1nova71 View Post
Are you sure it's full of coolant? Did you fill the engine through the top radiator hose? If you just put coolant in the radiator, it will not go into the engine and therefore not get to the back side of the thermostat so it won't open.
This is a MUST, and you should be OK...Jim
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Old 07-27-2016, 11:55 PM   #4
Bulldog88
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Re: Can't figure out why my truck is running hot

Yes it full I'm filling it up thru the water tank that the Silverado are equipped with, once it starts getting hot it spits water thru that tank and the small overflow hose that's there
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Old 07-28-2016, 12:06 AM   #5
71swb4x4
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Re: Can't figure out why my truck is running hot

Have you confirmed the temp? A bad radiator cap will allow it to spit out.
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Old 07-28-2016, 11:42 AM   #6
JAKA
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Re: Can't figure out why my truck is running hot

Is it possible the drive belt is routed incorrectly?
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Old 07-28-2016, 01:31 PM   #7
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Re: Can't figure out why my truck is running hot

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Originally Posted by Bulldog88 View Post
Yes it full I'm filling it up thru the water tank that the Silverado are equipped with, once it starts getting hot it spits water thru that tank and the small overflow hose that's there

Absolutely need to remove the upper radiator hose and fill the motor from there. It even helps to pop the steam vent line off to purge the air out of system.
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Old 07-29-2016, 07:56 AM   #8
homemade87
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Re: Can't figure out why my truck is running hot

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Originally Posted by Bulldog88 View Post
Yes it full I'm filling it up thru the water tank that the Silverado are equipped with, once it starts getting hot it spits water thru that tank and the small overflow hose that's there
This is your problem . You will never get the air out of the engine this way . Do as other suggested remove the upper radiator hose and fill . Sometimes it helps to raise the front of the truck also if you have a stubborn one .

Last edited by homemade87; 07-29-2016 at 08:02 AM.
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Old 07-30-2016, 11:30 PM   #9
Andy4639
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Talking Re: Can't figure out why my truck is running hot

Taking the steam port loose on the intake passenger side was the only way I got mine to work. Losen it up and when you see liquid coming out tighten it up and finish filling.
I also had the front end on a lift as high as it would go.
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Old 08-01-2016, 03:42 AM   #10
cmcolumbus
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Re: Can't figure out why my truck is running hot

I was having the same problem but after I filled it from the top radiator hose and removed the coolant sensor on one side and the plug on the other of the heads until coolant ran out everything was fine and had no problem.
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Old 08-04-2016, 10:14 PM   #11
cookseyb
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Re: Can't figure out why my truck is running hot

It helps if you raise the front of the vehicle up until the radiator is the highest point in the system. Fill through the upper hose until you think it is full, wait 2 hours and fill it again, repeat as necessary to remove the "air Lock" you currently have.
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