The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > General Truck Forums > Engine & Drivetrain > LSx Swaps

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 07-27-2016, 10:48 PM   #1
Bulldog88
Registered User
 
Join Date: Nov 2009
Location: DFW,TX
Posts: 233
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
Bulldog88 is offline   Reply With Quote
Old 07-27-2016, 11:06 PM   #2
ls1nova71
Registered User
 
ls1nova71's Avatar
 
Join Date: Dec 2009
Location: Independence Mo
Posts: 4,119
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.
__________________
My '72 short bed build. http://www.ls1tech.com/forums/conver...6-0-4l80e.html

5.3 swap into my RUSTY '71 C10
http://ls1tech.com/forums/conversion...71-c-10-a.html
ls1nova71 is offline   Reply With Quote
Old 07-27-2016, 11:18 PM   #3
oldman3
Senior Member
 
oldman3's Avatar
 
Join Date: Mar 2011
Location: West Plains, Missouri
Posts: 7,559
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
oldman3 is offline   Reply With Quote
Old 07-27-2016, 11:55 PM   #4
Bulldog88
Registered User
 
Join Date: Nov 2009
Location: DFW,TX
Posts: 233
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
Bulldog88 is offline   Reply With Quote
Old 07-28-2016, 12:06 AM   #5
71swb4x4
Senior Member
 
71swb4x4's Avatar
 
Join Date: Nov 2003
Location: Brookings, SD
Posts: 10,497
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.
__________________
Some people are like slinkies, they aren't good for anything, but you can't help but smile when you see one tumble down the stairs.
71swb4x4 is offline   Reply With Quote
Old 07-28-2016, 11:42 AM   #6
JAKA
Registered User
 
Join Date: Apr 2009
Location: Murray,KY
Posts: 39
Re: Can't figure out why my truck is running hot

Is it possible the drive belt is routed incorrectly?
JAKA is offline   Reply With Quote
Old 07-28-2016, 01:31 PM   #7
akdg87
Registered User
 
akdg87's Avatar
 
Join Date: Sep 2013
Location: fairbanks, ak
Posts: 339
Re: Can't figure out why my truck is running hot

Quote:
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.
__________________
build thread
1955 cameo turbo lsx
1993 K1500 Blazer 5.3/4L80e
2009 CTSV Sedan
akdg87 is offline   Reply With Quote
Old 07-29-2016, 07:56 AM   #8
homemade87
Registered User
 
Join Date: Apr 2010
Location: Guntersville Alabama
Posts: 1,073
Re: Can't figure out why my truck is running hot

Quote:
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.
homemade87 is offline   Reply With Quote
Old 07-30-2016, 11:30 PM   #9
Andy4639
Old member
 
Andy4639's Avatar
 
Join Date: Jan 2002
Location: Liberty, & Garden City S.C. , U.S.
Posts: 19,945
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.
__________________
1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver
Seeing the USA in a 71


Upstate SC GM Truck Club
2013,14 and 2016 Hot Rod Pour Tour


http://upstategmtrucks.com/



Get out and drive the truck this summer and have some fun!
It sucks not being able to hear!

LWB trucks rule, if you don't think so measure your SWB!
After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.
Andy4639 is offline   Reply With Quote
Old 08-01-2016, 03:42 AM   #10
cmcolumbus
Registered User
 
cmcolumbus's Avatar
 
Join Date: Apr 2007
Location: Hayward CA
Posts: 27
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.
cmcolumbus is offline   Reply With Quote
Old 08-04-2016, 10:14 PM   #11
cookseyb
Registered User
 
Join Date: Jan 2011
Location: Mullin, Texas
Posts: 16
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.
cookseyb is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 01:16 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com