No, it has power. But it might be down a bit. Not drastically. The engine has over 200,000 miles on it so I expect some power loss.
Just one. Theyāre still available
Cool.
These issues can be really frustrating. This forum has been really helpful. Another forum just cut me off because they gave me a simple solution (that had no effect on the problem) and couldnāt accept that the problem wasnāt as simple as their solution (fans).
This story about your neighbor hits home. I cannot find the problem but I wonāt quit until I do.
I canāt tell you (and everyone here) how much I appreciate the advice and suggestions.
Iām reading and re-reading every one and taking them all to heed and trying them all.
Whatever the problem turns out to be I donāt think itās any of the common, usual suspects.
I have a new radiator but when I put the garden hose to the one in the vehicle during the over heating it readily flows in both directions. Iām doubting itās the issue even though Iāve pretty much checked everything else. And I do mean everything.
Which is why Iām questioning the exhaust more and more. The moderator at the other forum told me clogged exhausts cannot cause overheating.
I wouldnāt have guessed that as a possibility absent a major engine power loss symptom, but a quick Google search suggests such a thing is indeed possible.
Can a Clogged Converter Cause an Engine to Overheat?
Yes, a bad catalytic converter can cause your engine to overheat. This happens because a clogged converter restricts the exhaust flow and stops hot exhaust fumes from exiting the engine.
A major blockage will heat up the exhaust manifold, cause catalytic converter failure, and raise engine temperatures, which can wreak havoc on the other engine components.
Note: The exhaust manifold is responsible for gathering up harmful gas and leading them to the catalytic converter.
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If the exhaust is so restricted that the engine overheats while idling, then the engine wouldnāt have enough power to be drivable.
I would still like to know if the correct water pump was installed and rotating the correct direction.
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Or defective water pump where the epoxy isnāt holding the impeller or hub/flange to the shaft allowing slippageā¦
I had a distributor do that to me on a SBC engine (on my owner of the company work truck I worked for at the time), had a strange misfire so I pulled the distributor and the drive gear teeth looked like razor blades at the bottom and the top of the gear looked newā¦ the shaft was walking up and down (kind of a known issue), so dropped a new dist in, set the timing and let it rollā¦ Came back with a crankshaft/camshaft correlation codeā¦ OKā¦ replaced the crank sensor (GM dealer part) (after checking the timing) timing was a little off, so I corrected it and thought that is strangeā¦
Boss was out of town and light cam back on and it was running bad, took it to the dealer and they said crank sensor, I said it is one of yours fix itā¦ code cam back, took back to dealer and they said the dist was 2 teeth offā¦ I thought no freaking way, they restabled the dist and he came back home (160 miles away) and it did it againā¦ I check and the dist was 1 tooth off so I pulled it and grabbed both ends of the dist and was able to turn the rotor on the shaft, the epoxy was not strong enoughā¦ Stupid thing drove me crazyā¦ lol
Here is a brand new, brand name different SBC water pump (replaced the day before) that came apart upon start up after replacing the alternatorā¦
New water pump and fan clutch, took out the radiator and bent the fan bladesā¦ Parts house didnāt like that warranty claim, but they replaced everything parts wiseā¦ you should have heard the noise it made, freaked everyone out in the shop, I just turn the key back off and laughed, this was a POS that just kept breaking, and crazy stuffā¦ The alt blew the bearing out while bleeding the cooling systemā¦ long story behind this thingā¦ lol
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The Cat could be Partially restricted resulting in running hot but not in a drastic way?
The temperature does not āsoarā but rather gradually keeps rising slowly.
This is what I installed recently and also years agoā¦same pump
Gates 41001 Premium Engine Water Pump
I donāt see how it could rotate in the wrong direction since it is driven by the same serpentine belt that drives the AC, power steering and alternator and all work. There really is no way to install the belt so the pump could possibly rotate the wrong way.
I would like advice on this because i think it is related.
When the engine is running the heater cores do not get hot. No heat comes out, except maybe a little when I first turn on the heater blower but it soon cools off.
Even if the radiator was clogged, the heater cores should still get hot.
I removed ALL hoses and reverse flushed them all and all coolant passages with a garden hose.
I could not find ANY restrictions to flow. I checked the heater cores themselves with a water hose. No restrictions found.
In the illustration below, I connected the hose at location A and water freely came out at O and Q.
From O to G no restriction.
I ran water from A to L to B and there was no restriction.
Iām wondering if the thermostat is not properly closing off the bypass hose port once warmed up so that water always flows from E to D ? This would lower water pressure to the block and heater cores across the board.
Maybe someone can make sense of this but I canāt.
Remember the water pump is new. The thermostat is new. The radiator cap is new.
There is no oil contamination in the oil. The compression is good. No loss of coolant.
No odd odors or steam from the exhaust. All 6 spark plugs look good and clean. Not oily.
If coolant was mostly bypassing the engine block through the bypass port?
More and more I think I may be getting the wrong thermostat from the auto parts store for this vehicle. Your post looks more and more relevant.
There is in fact a hole in the bottom side of the thermostat housing for the bypass.
I see no way the thermostat I am being sold could in any way close off that bypass port.
The type thermostat in the photo you posted seems it would have a better chance of working to close off the bypass.
I still think water is bypassing the block through the bypass port making the water in the block hotter than it should be. ORā¦there is some kind of fitting that should be in there that is missing?
But the Factory Service Manual doesnāt mention anything like that.
OMG.
I am not ashamed to admit when I have made a huge mistake.
I deserve any ridicule.
Nevadaā¦I think you nailed it.
The factory service manual shows the belt on the 3.3L engine going over the TOP of the water pump pulleyā¦ I went out to the vehicle and checked the belt ā¦and it was ā¦going around the bottom of the water pump pulley. I overlooked it. Critical.
That would make the water pump spin backwards.
Apparently, at some point when the belt was loose after I took it off, I installed it under the pump pulley (and it tensions as if it is on correctly and like a doofus, I didnāt verify it.)
This has to be the solution to this entire fiasco. OPERATOR ERROR.
DUMB mistake. Failure to verify.
God bless you and thank ALL of you for your patience and help with this.
You are all great people and I wish I could throw a barbecue and treat you all.
I end up with a vehicle with lots of new parts which most needed replacing so I am happy.
I end up being better educated.
Iāll post a final after getting all back together but this HAS to be it.
THANK YOU ALL SO MUCH !!!
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Glad you got that pesky overheating problem resolved. Good job.
In retrospect the critical test for this sort of conundrum would be to somehow measure the coolant flow rate.
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Thanks for all your help Mr. George. 
I had mentioned earlier that I didnāt really see any coolant flow through the radiator.
That was a sign I should have heeded.
I still donāt see how this thermostat has any affect on the bypass?
It may not need to in that design. Still worth spending a bit of time to verify and be sure.
Hey, I understand how you feel but you should also be relieved it was nothing serious. Thatās a big win compared to some other scenarios. Glad to hear you found it!
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I āfound itā because of Nevada and good people like you.
Thanks again!
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For future reference.
As a good rule of thumb, smooth pulleys get the smooth side of the belt and grooved pulleys get the grooved side of the belt, so grooved to grooved and smooth to smoothā¦
Just remember you canāt buy experience, but it sure does cost a lotā¦
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I am VERY disappointed to report that after a test drive it STILL overheats !
I took it out this morning after getting it all back together all happy and anxious to see how cool it runs now, and s-l-o-w-l-y it kept climbing right back up to 225F and still climbing while moving!
I reinstalled the serpentine belt the correct way and it helped (a little). It should have been a massive difference? The engine is still unable to shed enough heat to keep up with the build up of heat so here I am again. Changing the belt was part of the problem, but there is still something major causing it to not cool down.
It does not seem to cool down while Im moving so what the heck?!
On a positive note, the heater works now and the fans seem to come on perfectly at the right times.
Iām back to either the radiator is bad or a clogged CAT?
With that in mind, I need to also make sure the condenser core is not flow restricted.
The AC works great and air comes out ice cold. I tried driving without the AC and it made little if any difference.
The ONE thing that seems to have an effect on cooling down the engine somewhat is if I turn on the heat full blast while driving (itās going to be 98F outside today)
Has motor boiled over? Blown coolant? Iāve bought several cars with bad head gaskets and some had visible coolant stains. The last one I got had zero coolant stains. Turns out it had been misdiagnosed. It just happened to be a car model with a known history of head gasket issues.
That is a good sign that your radiator is not big enough or restricted, and not able to cool the vehicleā¦ and since you have the OE size radiator (well I hope anyway lol) I am going to say your rad is restricted.
Turning on the heater full blast is like adding an auxiliary mini radiatorā¦
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Never boiled over as far as I can recall. I would always pull over and stop at the first sign of overheating and let it cool down. This is not the first time in this vehicles history that I have had over heating issues.
No leaks. Not losing coolant. Compression just tested. No odors (sweet or otherwise) from the exhaust)