Staying Warm

[Bob Myers]

Mine was blowing just lukewarm air, I had resigned myself to replacing the heater core, and did in fact pull the old one out. Just for giggles and such I attempted to run water through it from a garden hose. It only trickled out for a few seconds then started flowing better, and finally flowing good. I let it run for probably 5 minutes under full house pressure(about40 psi) and drained it and put it back in. Heater works great, had I known it would be that simple I could have done it without popping the heater box off inside. Give the flush deal with a garden hose a try, all you have to lose is a few gallons of water and a half hour of time. Pull both hoses off at the engine, point one of them down and stuff the hose into the other,,,,,,let'er rip. As far as an air bubble in the system goes,, if you jack the rear of the truck up 4 foot off the ground, and fill the cooling system, then yes there may be an air lock in the heater or the back of one head. As soon as you let the jack down the airlock will come out. I vote more more a partial clog or restriction caused by not using the heater than any kind of air lock.