1991 Chevy Silverado 14 heater cores

1991 CHEVROLET SILVERADO

179,000 MILES • V8 • 4WD • AUTOMATIC

1991DUALLY4X4

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I am the second owener of my truck and on the 2nd year of ownership I started to blow heater cores. Currently I am on #14. The heater core has been tripple grounded and since this all started I have replaced the motor, radiator, water pump. All of this has been completed by a chevy dealership and 4 of the heater cores have been done by and outside mechanic. All certified and all came with warranties. Each heater core will last 6 - 12 months depending on how often I drive my truck. half of the time is with a fully loaded camper pulling a boat and the other half of the time is just normal driving.

hope you can help!

John

Dec 23, 2008 at 2:02 PM

BLACKOP555

CAR REPAIR CONTRIBUTOR
10,386 POSTS

are you using a brass, copper, or aluminum heater core?

also try a different kind of coolant. might be incompatable.

check the voltage of the cooling system to see if theres not enough grounding, shoudl be good due to the fact that the radiator isnt going out?

Dec 30, 2008 at 8:06 PM

1991DUALLY4X4

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I am using an aluminum heater core and have tried a different coolant. The dealership check the electrolysis after changing the heater core and it was still a bit high.

Thank you for your help.

John

Dec 30, 2008 at 10:05 PM

BLACKOP555

CAR REPAIR CONTRIBUTOR
10,386 POSTS

cut your heater core hoses and put in brass pieces and hook grounding straps to them too to even further get rid of the problem.

the next thign could be you are gettign too much flow through the heater core, you may have to add a flow restrictor in one of the lines to slow it down a bit.

Dec 31, 2008 at 3:39 PM

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