replace heater core or flush?

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AaronW

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All: I've got my 89 3500 crew cab completely apart, and am about ready to start putting the whole thing back together. I was thinking that I'd go ahead and replace the heater core, as long as I had it apart. The heater worked ok before, but I have no idea how old the core is. (And if it matters, my truck has AC, though it doesn't work).

I see that it is possible to flush out a heater core. Would it be smarte to flush the core out and put it back, or do you think it would be dumb not to replace the heater core, as long as I've got the truck all apart? Looks like I'm gonna be about 70 bucks for a new copper heater core, and I'm trying to decide if that's $$ I can afford to not spend now, or if I'm gonna regret it later.

Aaron
 

fast 99

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Really a crap shoot. What condition was the coolant? Do any of the heater box bolts appear to have ever been removed? Did it adequately heat before? Myself, I would replace it but that's me.
 

AaronW

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Really a crap shoot. What condition was the coolant? Do any of the heater box bolts appear to have ever been removed? Did it adequately heat before? Myself, I would replace it but that's me.

Not sure on the coolant, as I wasn't the one who pulled the engine, but it did heat the cab ok, before. Hard to tell on the bolts. Right now, I can't even get the darn thing apart. I figured I'd at least pull it apart and check on the condition of the gasket inside that separates the heat from the AC. I watched the Brothers video on pulling the heater core, but mine appears to be set up a bit different, and I'm scratching my head as to how to get it apart. In the top view, you can see that there's a hinge pin sticking up through, that would have to come out. I'm not sure how to get that out of there, or if that's my only hangup.

Ideas?

Aaron
 

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rpcraft

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If you have the heater box off and all the front end apart then replace it with a quality unit, like from Spectra. The heater core is cheap relatively speaking, maybe 60 bucks at a parts store depending on which brand and store, and doing it on the side of a road with fender, exhaust manifold, blower box, and motor in the way does kind of suck, at least that was my last experience...
 

peats

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Replace it now,or it will leak later. Ask me how i know!!
 

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