Opinions on Radiator Usability

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1987 GMC Jimmy

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I bought this radiator on eBay to replace the plastic POS that my car has right now. It came out of an ‘83 Olds Toronado with a 307. I’ve only dealt with the OEM radiators that came in square bodies so this one’s throwing me off a little. The dimensions are close to the aftermarket one I have now but not the same. The core is a little less than two inches longer (28.25”) on the Toronado radiator vs. 26.375”), but the overall width difference is about an inch. There doesn’t appear to be a height difference, and the thickness is about a half inch more on the Toronado radiator. It has three cores, which I’m assuming the one I currently have has two. The trans cooler ports are also the same distance apart from each other. The weird things I’ve found are that the petcock faces down instead of to the side, but it’s on the inlet side, and there’s a big hole in the bottom of the core support to accommodate it; it’s made here instead of Mexico, and there’s no port for the heater hose so I’d have to run that hose back to the water pump. The inlet is also damaged, I don’t know if my rad shop can fix that properly, and I can’t ask till Monday. What do you guys think? Also, @CorvairGeek do you have any dimensions on your radiator? I’m thinking the original was the smaller core, but I’m not 100%. Also, is this what yours looks like? I want to get the right thing, but if this fits, and it cools better, I can live with that.

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CorvairGeek

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My assumption is that is an original Harrison radiator. The original petcocks are pointed down (there is a matching hole in the radiator support) and were no mess to drain. I've only seen that on the originals.
I don't have any original dimensions for the radiator (I replaced mine in '91 with a heavy duty Modine, now a plastic and aluminum replacement), but they were very different than the aftermarket.
Keep in mind that there were also wider radiators in the B and C bodies before our cars. The A/C lines were routed differently and the plastic baffle on the driver's side was wasn't used with the wider radiator.
My heater core never was plumbed through the radiator, that started somewhere after '85. I don't like that capped port on my current radiator.
 

CorvairGeek

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Keep in mind the amount of debris that can be in a transmission cooler can be staggering.
We picked up a nearly new radiator (amazing how many nearly new parts are on junked cars) for my daughters car from our U-Pull-It yard with black transmission fluid, pretty obvious why the car was scrapped. Rather than the $10 a can cooler flush, I used a side can tap and old A/C hose from a cheap gauge set, and screwed a fitting into the cooler and flushed it with cans of brake cleaner. The amount of clutch material dislodged (forward and reverse flow) was shocking and would have ended up in a perfect transmission. Even ran a quart of transmission fluid through it with the engine running before I hooked up the return line.
 

1987 GMC Jimmy

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My assumption is that is an original Harrison radiator. The original petcocks are pointed down (there is a matching hole in the radiator support) and were no mess to drain. I've only seen that on the originals.
I don't have any original dimensions for the radiator (I replaced mine in '91 with a heavy duty Modine, now a plastic and aluminum replacement), but they were very different than the aftermarket.
Keep in mind that there were also wider radiators in the B and C bodies before our cars. The A/C lines were routed differently and the plastic baffle on the driver's side was wasn't used with the wider radiator.
My heater core never was plumbed through the radiator, that started somewhere after '85. I don't like that capped port on my current radiator.

Okay, I do have a piece of baffling on the driver’s side, which makes sense. If there was a B Body heavy duty cooling option, I didn’t get it. I’m thinking that’s a station wagon thing. My heater was routed to the water pump before I replaced it, but I couldn’t for the life of me remove the plug, and I had to reroute to the radiator. I’d like to keep this one, but if I have to replace it, I’ll just send it back.

Oh, what made you have to replace your radiator so early on?
 

CorvairGeek

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Even by the era of ours, the baffle was still used even with the V08 heavy duty cooling option. I can't say I have seen the wider radiator used after 1979 (engine sizes decreased for 1980), but the diesels may have been an exception.
My original radiator got so it would not flow air! There was all sorts of fine chaff and fuzzy stuff packed into the fins, and the fins were crumbly. Not quite sure why it was so bad. The condenser was clean too!
 

1987 GMC Jimmy

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Alright, I’m going to see if I can find the smaller radiator, and if not, I’ll see about making this one work.
 

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