I own a 98 Diamante and I am having a problem with the Heater Core (again) about 4 years ago the core was replaced and the problem has re-occurred. The last time I took it to a mechanic. This time however that is not an option due to my finances. I have replaced the Heater Core on another vehicle (2000 Ford Expedition) it took me about 13 hours due to the massive center console that had to be removed to move the dashboard out enough to get to the core. But I had instructions so I did not break anything or miss any bolts.

I am looking for any type of instructions that I can piece bolts to a removal step. Or an order of the way I should remove things.

 

its NOT the heater core, but rather the "o" rings that seal the nipples to the core.


Heres a fix that HONESTLY works in this case. Go to GM, and buy a pack of their coolant sealant tabs. they're basically crushed wallnut shells. Add 3 to your cooling system.

I am not a fan of this kinda repair, but the leaking "o" rings are the perfect candidate for this band-aid repair. And it DOES work. Its worked on every diamante Ive tried it on.

 

Thanks for your help with this. Next step to find a GM dealer near my route home!