Overheatring Problem 1994 Chevy Caprice Classic

Recently replaced the passenger side electric cooling fan motor as it had burned out due to becoming jammed up with snow/ice during a storm but now the dam car is still overheating. Well the gauge says it's
getting too hot, the needle is going al the way to the left to the point to where it almost touches the red, the car has not actually overheated as of yet, I have not allowed it to do that yet.
It does get real hot though, so hot in fact that it's hard to start some times when the needle is that far over. Any suggestions now why? The coolant is full, the oil is full both are fresh and the coolant is a 50/50 mix of anti-freeze/water god for about 24 below zero which I need here in the northeast.
Could it be the thermostat causing me this trouble, to be honest I can't remember that ever being changed on this car since I've owned it and I bought it new :) so that would be one hell of a life out of a thermostat, over 100k miles so far.
Any other suggestions on why it may be overheating? BTW the drivers side electric fan is working.
Thanks in advance.
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What engine?
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It's the 350 engine, not sure what that is in terms these days but it;s the good old 350 engine that will never die :).
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wrote:

That engine is an LT1--like the Corvette engine, with tuned port injection and reverse flow cooling--cools heads before block to allow pump gas w/o detonation. The t'stat is actually a 2-stage unit which controls the flow of water in 2 directions, 2nd one to prevent icy-cold water from flowing to the engine(& thus prevent shock to an otherwise warmer engine) for cooling. All this allows the engine to operate at an elevated temperature--the fans normally don't come on, ac excluded, until the engine reaches around 228 degrees F. Leaves little room for error, huh? Factory unit is a 195-degree one. DON'T BUY THE 160-DEGREE ONE UNLESS IT ABSOLUTELY WON'T COOL OTHERWISE. You'll find this to be a slightly unusually expensive t'stat. But with 100K already on it, it owes no more service. Replace with one from genuine GM store--Chevrolet or Pontiac should have them (for Z-28s/'Vettes @ Chev and for Trans Ams @ Pontiac). It is a critical part--even more so than on 'normal' engines. HTH, s
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wrote:

I bet there's at least one pressure switch in the a/c system that'll turn the fans on.

Cool info. I wonder why the reverse-cooling isn't used on more vehicles. Did the '92 year come with any of those unusual features?
I know the one I worked on didn't have electric fans at all, and it appeared to have a massive TBI unit on top of the engine.
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Sure it could be the thermostat. That would be a rather likely cause for a car this age. Change it out. You can take it out and put it in a pan of water on the stove and watch to see if it opens, but unless you have a thermometer to indicate the temperature of the water you really won't be able to tell if it's opening at the right temperature.
You say the coolant is fresh - how fresh? If you recently changed it, there's a good possibility of an air bubble in the system. They can be a pain to evacuate sometimes.
I'd certainly go with the thermostat first.
--

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On Thu, 2 Feb 2006 12:57:31 -0500, "Mike Marlow"

Fresh within say 4 - 5 months I'd say and everything was great until that damn fan locked up with slush and then the problems started. Funny thing is they changed both the fan and the fuse, I forget exactly what they called it, looked like a normal fuse on super steroids was like 20X bigger than an normal fuse, I've watched both fans work so I know that they are working? Baffles the hell outta me. Could a fan motor burning out like this cause a thermostat to go bad because it raised the temperature in the system to go sky high? New one on me I guess.
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I know this isn't what you really want to hear, but at some point, you just give up on the "cause and effect" pursuit and drop back to basic troubleshooting. It is so easy to go down rabbit holes - even more so when trying to give advice over the internet without the car right there in front of you. So... in the name of dropping back - I'd replace the thermostat simply because it's old, and old means likely to fail. They are a common failure point. I would ignore the preceding fan incident for now and simply look at the presenting symptoms.
Frankly, I suspect the thermostat was going before the fan went. It may well have not been opening fully. The car really should have cooled well enough with just one fan during the winter time. Hell - if it's cold enough, with no fan.
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just
when
front
simply
Good summation. I agree completely.
Dave
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Have you actually seen the new fan run ???
I would look at the fan FUSE ! When I burned out a fan, it also took the fuse. The fuse was a "wire fuse" buried in a bundle of cables......
Helluva job to find without the wiring diagram.

<rj>
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Under what conditions do the temps get high? Idling? Driving down the road? Both?
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On Thu, 02 Feb 2006 17:59:56 -0500, NickySantoro

Both, does not matter what it does, takes a bit longer to get up to the higher temps now with the passenger side fan working now but is still does, also when it's colder out nighttime, when I run the heater up high etc.. it takes longer for it to reach the higher temps. it's never as I said actually gotten into the red.
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wrote:

That was an important bit of information. Overheating while driving down the road helps us rule out variables (such as an inoperable cooling fan). Certainly you should change the thermostat and any radiator hose that looks deteriorated. Overheating while driving down the road is pretty much never a cooling fan problem. You only need the fan or fans while sitting still or driving at very slow speeds, especially in the winter. A thermostat problem or an airlock problem perhaps........
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