I have gone thru 4 front heater cores in 6 months. Any ideas as to why? I live in Ontario, Canada and it's getting cold so any help would be great.
Thanks
Tankerguy

 

Are they new or used? Where do they develop a leak from? Was a coolant flush performed?

 

Let me give some more details as this may help solve my problem. 1995 Astro AWD 459000 kms. original heater core started leaking in may so I bought a new one, flushed the cooling system and installed the new heater core along with new heater hoses. This lasted 5 weeks, then started to leak. I figured it was faulty so I exchanged it for a new replacement which lasted 4 weeks. Same thing again, so I switched to a different manufacture, (from specter to GM) This didn't solve anything, the heater cores last on average 4.5 weeks. My parts supplier won't give me any more cores under warranty. I haven't done a system pressure check yet, I started to do some research because I was told that this may be caused by a bad head gasket.

 

Can anyone tell me if you need to remove the dashboard to get to the front heater core of a 2000 Chevy Astro Van?

 

I had the same thing happen on my '93 Silverado. The most logical opinion I received from my inquiries and studies as to why it was happening was "electrolysis".
The way I understand it is that the coolant is somehow turned acidic due to contact with an electrical current (maybe a short or improper ground somewhere?). Anyway, the acidic fluid eats through the tubes in the heater core.
It's been awhile and I'm no chemist so I may be a bit mixed up as to how it happens. However, google search electrolysis and heater core and see what you can come up with. It's worth a shot.
By the way, my fluid was very neglected. After I did the radiator flush I never had it happen again. Good luck.

 

what steve v is talking about is probably the culprit in this case.
when a liquid(anitfreeze) passes over 2 dis-similar metals(aluminum,steel, cast iron,copper) it becomes an alkaline. one way of testing ths theory is to take a DVOM(Digital Volt Ohm Meter) and connect one lead to ground, and stick the other lead into the antifreeze in the rad. you will get a voltage reading.
This is one way of testing the antifreeze to see if you're due for a change.
one thing that does help is to add a ground wire to your heater core when you replace it

 

melmor, sorry to have neglected your question. I just now realized the other posts were from last year. Here are the steps for your heater core removal per my Haynes Manual. It says to do it on a completely cool engine.

1) Disconnect negative cable from the battery
2) Drain the coolant
3) Remove the coolant reservoir
4) Remove the windshield washer fluid reservoir mounting bolts and move it aside.
5) Loosen the clamps and detach the heater hoses from the core tubes. Plug the core tubes.
6) Working in the passenger compartment, under the dash, remove the heater core cover screws. (the illustration shows 5 of them)
7) Remove the 2 core mounting screws at the rear of the core.
8) Lift the core out of the housing.
9) Installation is the reverse of removal. Refill the cooling system and check for leaks.

A Haynes manual is the first thing I buy whenever I get a different vehicle. They cost about $20 at any auto parts store, and they show detailed, step-by-step instructions with photo illustrations. Good luck.

 

Below is a a link to an AC Delco article about electrolysis and heater cores.

Steve V

http://www.sandyblogs.com/techconnec...ctrolysis.html

 

Hi,

I need to replace the heater core on this car. The manual I have on CD has hard to see pictures, and I cant really see whats going on. Does anyone have, or know where I can get, a clear step by step procedure on how to do this?

Thanks,

Dave