Re: New Aluminum Radiator Over Heating!!! :( :(

Guys,

> I just bought a new custom radiator for my 90 YJ. The YJ has a 1994 > Corvette LT1 in it, so I guess this makes this question a bit off topic. > But, Bill Hughes is always listening. :) LOL. In any event, after > installing this monster aluminum radiator, the jeep seems to exibit some > strange behavior. When you sit at idle, the electric fan keeps the > temperature down. But, if you go ANYWHERE, the temp rises immediately. I > can't even make it a mile without it going up to 235+. In any event, I've > just (at the same time) put a completely new thermostat (180 degrees) and > new water pump on the engine. But, the behavior almost seems like what > would happen if the water pump just weren't pumping. Since the cooling > system is the reverse flow, it is difficult to tell if the pump is pumping > at expected rates. Is there a test to make sure that it is? Bill, anyone, > any thoughts? It is a pretty defeating feeling after spending that much > money on a radiator, SPAL fan, water pump, thermostat, and a bunch of > gaskets. Any suggestions are appreciated. > TIA. > Scott > > FYI, it's a 90 wrangler with a 94 LT1. The new radiator is a custom build > from Ron Davis Radiators. The electric fan is a SPAL high flow fan. There > is a custom shroud on it too. > >

Are you absolutely sure the water pump is turning the right way? It is quite common for the parts stores to supply the wrong one. Also check your hoses to make sure they are up to snuff and not able to collapse. The other thing I would check is that there is no air in the system. I know these are basics, and maybe you have checked already.

Chris

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c
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Could your temp gauge be wrong? With an engine conversion, it's easy to get wires crossed. Try a mechanical gauge. Also, run with the radiator cap off so you can check for flow. Remember to carry extra water with you to replace any lost coolant.

RollOver Pete... Check me out at:

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RollOver Pete

Reply to
L.W.(ßill)

Question for you.

Was it running before you did this work on the rad and waterpump?

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Scott wrote:

Reply to
Mike Romain

Yes. It was running. The original radiator was a 3 core that was a bit too small. So, when I hit it hard, it would slowly get warm (but only when it was 100+ outside). Now, it's a disaster. Did you read what Bill said about the thermostat? Is that true? Wierd stuff huh. Amazing how it could go from ok to disaster so fast. Any ideas?

Reply to
Scott Tate

Do you still have your original water pump? From your description of what happens you have the wrong one on the engine now.

Earle

immediately.

Reply to
Earle Horton

Earle, is it possible to put the wrong one on? The water pumps are 100% identical in every way. Scott

Reply to
Scott Tate

Reply to
L.W.(ßill)

Sounds like the wrong pump to me.

Ensure that you bought the correct pump. It is my understanding that the pumps for serpentine belts spin the opposite direction of pumps for v-belts.

I have seen two Jeeps with Chevy LT1 conversions exhibit your symptoms after the water pump was replaced. In both cases, replacement with the correct pump cured the problem. Both owners told the same story about the sepentine -- v-belt differences.

Robert Bills KG6LMV Orange County CA

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Reply to
Robert Bills

Reply to
L.W.(ßill)

Bill, someone removed the expansion tank for the rad fluid that hooks up to the rear of the heads, the one that allows the air to come out of the heads thinking it was a 'closed' system tank like on an XJ.

He sure could be describing air locked heads.

Could also be why the old setup ran hot. The previous owner must have opened the plugs on the heads to purge the air out and maybe left a bit of air in there.

Mike

"L.W.(ßill) Hughes III" wrote:

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Reply to
Mike Romain

Reply to
L.W.(ßill)

No radiator is perfect, but aluminum radiators have definite advantages over copper/brass units. I still think there is something else going on here, and the reverse rotation water pump (or lack of one) makes the most sense.

I push aluminum radiators hard in most of the posts you see from me on this NG, and it is certainly possible that in this case Scott may not benefit from one. After all, look at the extreme temps he has to deal with. Still though, I have yet to see an aluminum rad that couldn't out cool a copper/brass unit.

If in fact everything else in his cooling system is in good shape, correctly matched, and there are no major blockages to the water flow, I find it hard to believe that he is having these problems. I would suggest maybe going back to the radiator he took out, just as a reality check.

Please let me know how this turns out. You have my interest now.

Reply to
Red Racer

He just found the head bleeder tube hidden under the plastic center cover, he should be good to go...

Mike

"L.W.(ßill) Hughes III" wrote:

Reply to
Mike Romain

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