red coolant inside my blazer

[dwitczak]

I am getting the red coolant dripping (at a good rate) onto my passagener floor board.

I have a 96 blazer with 4.3.

6 months ago I replaced the heater core.

I just had the driverside head removed and a rocker replaced acouple days ago. they also did the distibbuter and spark plugs. could they have damaged something?

thanks for all your help.

Dan

[old_master]

It's doubtful that they damaged the heater core. It is very well protected inside the heater case. The fact remains however, the heater core is the only component that can allow coolant to leak into the interior.

A very common cause of heater core failure is electrolysis. It is caused by poor, loose or missing ground connections, a lack of adequate cooling system service, inadequate or improper coolant properties. Test with the engine running at operating temperature. Make sure that all engine ground straps are in place. Using a digital voltmeter: Place the negative lead to the battery negative post and the positive lead into the coolant. A voltage reading above 0.3 volts can cause pinholes in the heater core.

[blazee]

Originally Posted by old_master

It's doubtful that they damaged the heater core. It is very well protected inside the heater case. The fact remains however, the heater core is the only component that can allow coolant to leak into the interior.

A very common cause of heater core failure is electrolysis. It is caused by poor, loose or missing ground connections, a lack of adequate cooling system service, inadequate or improper coolant properties. Test with the engine running at operating temperature. Make sure that all engine ground straps are in place. Using a digital voltmeter: Place the negative lead to the battery negative post and the positive lead into the coolant. A voltage reading above 0.3 volts can cause pinholes in the heater core.

A bad case of electrolysis can cause heater core failure in a matter of days. Your new heater core could have easily failed in 6 months.

[old_master]

The same holds true with the radiator also.

[OverBoardProject]

I don't know how long I've been working on cars and never heard of that until today. Is it the same with the old green antifreeze?

[blazee]

It can occur with all antifreezes. Check out my posts in this thread if you want more info about it.:
http://www.automotiveforums.com/vbul...d.php?t=469926

[OverBoardProject]

Thanks Blazee, Although I doubt that I have a problem I'll check mine tomorrow to see what it sayes. I might be wrong but I believe that my 85 still has the origional heater core and it still blows enough heat to cook a meal on

[mike2004tct]

Originally Posted by old_master

A very common cause of heater core failure is electrolysis. It is caused by poor, loose or missing ground connections, a lack of adequate cooling system service, inadequate or improper coolant properties. Test with the engine running at operating temperature. Make sure that all engine ground straps are in place. Using a digital voltmeter: Place the negative lead to the battery negative post and the positive lead into the coolant. A voltage reading above 0.3 volts can cause pinholes in the heater core.

Check your antifreeze, and remove unwanted hair ALL at the same time.

[Rick Norwood]

Bad Heater Core is causing the leak as Old Master stated. See my post in FAQ about Basic Coolant System Advice. But you can remove both heater hoses at the Firewall and jumper the two hoses together to buy you some time. You won't have heat, but you will be able to drive the Truck.

[dwitczak]

I FOUND THE PROBLEM. It must have been the recent mechanical work I had done. The bigger of the two coolant lines connected to the heater core was not connected, only butted up against. I connected it and no more leaks.