Chevy techs, please put your thinking cap on.

7423 · 04-01-2012, 12:58 PM

I have a 1998 1/2 ton GMC Savana with a 5.7 vortec.. At 120,000 miles, the intake gaskets leaked water. After changing the gaskets, the leak is gone but the motor will not get to normal operating temperature. We have changed the thermostate 3 times with the correct style 190. degree for the vortec. The oe temp gauge climbs to 200 degrees, the thermostate opens and it drops to 140 degrees. It will do this all day long. I have cardboard in front of the radiator. The radiator hoses never get over 170 degrees there fore the heater never works. The heater control valve works properly with a vacuum pump attached. I live in SoCal where most days are warm. Any thoughts??

04-01-2012, 12:58 PM	#1
7423 Senior Member Join Date: Dec 2006 Posts: 639 Likes: 0 Liked 1 Time in 1 Post	Chevy techs, please put your thinking cap on. I have a 1998 1/2 ton GMC Savana with a 5.7 vortec.. At 120,000 miles, the intake gaskets leaked water. After changing the gaskets, the leak is gone but the motor will not get to normal operating temperature. We have changed the thermostate 3 times with the correct style 190. degree for the vortec. The oe temp gauge climbs to 200 degrees, the thermostate opens and it drops to 140 degrees. It will do this all day long. I have cardboard in front of the radiator. The radiator hoses never get over 170 degrees there fore the heater never works. The heater control valve works properly with a vacuum pump attached. I live in SoCal where most days are warm. Any thoughts??