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Discussion Starter · #1 ·
Car has 32K on it and is gorgeous all around including the engine and undercarriage. Car runs very hot out here with the needle damn close to the top but still in NORMAL range. Pressure tested the system and no leaks. Changed the coolant too. Car still runs hot . Noticed I said " out here"? "Out here" is Las Vegas and it's been between 105 and 119 while this is all going on. Yes, the temp gauge is staying in the NORMAL range but damn near the end of it. The fan clutch seems to be testing good as too what Ive seen online. Should I worry about anything?
 

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Discussion Starter · #4 ·
Might have found the problem.....testing the cap right now and its a 16lb. Test tool just came from Amazon btw. Pumped the cap up to 16lbs and it seems to be loosing pressure. Unless the brand new test adapter is leaking, lol! Guess I'll go get a new one just too see.
 

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The pressure cap has little to do operating temp. It keeps a lid on the boiling temperature. That extends the coolant as a liquid to much higher temperatures so as such is more likely to keep the coolant as a liquid than a useless for cooling purposes a gas as in steam and alcohol vapor from the water or glycol fractions of the coolant.

The temperature drop is a function of the difference between ambient temperature and coolant temperature. The colder the air passing through the radiator the cooler the coolant will become. Holding up how cool the coolant can become is the job of the thermostat.

How much heat can transfer in terms of BTU’s is also a function of area which at the highest level is simply is the face area of the radiator. But as always the devil is in the details, so within the face area of the radiator the tube number, size, shape and location counts for a lot as does the that of the fins.

Sometimes you can pick up some cooling with a high flow thermostat if the one you have is topping out on flow where the system might prefer more flow. But given we seldom really know what the optimum deliver rate is this change is guesswork that may or may not produce a change.

Considering it’s hotter than hell and your probably cruising around with the air-conditioning on so the engine running on the high side of normal doesn’t sound too bad for a 32 year old vehicle.

Bogie
 

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How much faith can you have in the original, in-dash temp gauge, anyway?... How accurate is it? Maybe try a good aftermarket gauge (even temporarily) to get an exact value, then see if you should worry. A temp gun to read the temp on the rad hoses can also give you a pretty accurate number.
On the other hand, having a car run on the high side of normal in Vegas in the summertime might not be that surprising. Remember also that new cars have temp gauges that do not show the variation of temp while driving, they stay stuck to the middle unless there is a real problem, so maybe if you are used to modern cars, seeing a needle move up a bit scares you for no real reason?...
 

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Discussion Starter · #7 ·
This car has 32K on it. I changed the antifreeze last week and it already looks a little dirty. Suggestions? Change it again? Im thinking its got crud built up inside.
 

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Discussion Starter · #9 ·
The minute I started going downhill the gusage got cooler. So i'm figuring an air flow problem. Bottom line is that the gauge is fine and it was the fan clutch. Although the car was not overheating, the clutch wasn't operating at its full capacity. Once I compared the drag to a new one, it was obvious. Just took a 60 minute ride in 110 degree weather with AC and the needle just about hit the half way mark. Its all good now
 
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