Normal Operating Temperature

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May 27, 2004
Savannah, GA
I just changed my fan clutch, water pump, all radiator hoses, oil cooler hoses, thermostat and belts. My temperature is now running a little over the halfway mark. Before the changes it was running similarly but my water pump was bad. I burped the system and have no leaks. Just wondering what some of your normal temperatures are?

Mine was running at about 1/4 to 1/3 of the way up before my cooling problems started. I made essentially the same changes you made (plus the radiator) and it's now right back where it was before.
mine runs cool i guess. never over 1/4 th for me. usually even cooler.
bigbrown said:
mine runs cool i guess. never over 1/4 th for me. usually even cooler.

Same here.
OK. Thanks.

This is only at idle, about a 15 minute running time. My oil is clear and clean. No evidence of water or coolant.

Any suggestions of what it might be?
mine always sits right at or jst over halfway
False hot readings are common after drain/refill of coolant. I've drained and refilled the coolant in my 60 several times for similar reasons as you, and each time the temp gauge showed "too hot", like halfway to 7/8 up for a while even though the actual engine temp seemed fine(felt normal, no hot smell,etc.) My solution has been to just drive the vehicle normally and eventually it has always gone away(the high temp reading, not the vehicle). Many here have used a "burping" procedure to dislodge trapped air pockets in the cooling system which are the assumed cause of the false temp readings. Maybe do a search on "burp + cooling system". Gotta get one of those non-contact infrared thermometers someday.
did you replace both top and bottom gaskets for your thermostat???? that will make your LC run cool. the coolant is always circulating and doesnt have the time to reach the proper temp. found that out the hard way last winter...lololol......many a cold day driving around
before replacing fan clutch...3/4 or higher.

after fan clutch...never higher than 2/3

I had to burp a couple of times, but after that it always runs 2/3, even with the cardboard on the radiator.

What is the best process to burp the coolant system?

Sorry about the hijack but, I seem to get a lot of gurgling noise coming from around the passenger side dash area. Any thoughts?
Good things here.

Yeah, I burped the system last night. It was still running higher than normal, but I have yeat to drive it "normally" (as in on the road). I drove the wife's car to work today just in case. I guess tomorrow I will drive it and see what happens.

I did replace both gaskets in the thermostat.

I think I will be ok, but will keep you posted.

Thanks, all.
I bought a new temp sender and threw it in since they're cheap and it read extremely high. I thought my old one was giving me the wrong readings and my engine had been close to overheating the whole time, but then I bought an entire aftermarket guage system and threw it in just to get some numbers, and it said it ran at about 90 degrees C. I would think that's a good temp, so I concluded the sender was bad. Also in the FSM it gives some resistances to check against temperatures. Mine was way out of range (too little resistance). So maybe a second opinion and a resistance check would be good.

Zachary Rothe
Well, I drove the Beast to work today (45 minutes one way) and the temp stayed between 1/2 and 3/4. It didn't seem to get any higher than the 3/4. Turning the heater on full helped bring it down a bit... does this indicate anything or is it normal? The good thing is no leaks. Could a loose belt on the water pump cause a higher temp? Mine seems fine... just asking.

I do get the spikes in my fuel and temp gauges sporadically, so I am planning to clean the contacts. Maybe I do need a new temp sending unit. I dunno.

Anyone? Thanks.
which thermostat did you get? there are two different temperature thermostats that open at different temperatures. also with my truck the ground on the gauge does not have a good connection and will peak randomly. maybe if you clean up the ground it could help?

i dont know if this is relate to you but i figured i would throw in something that hasnt been brought up yet.
Thanks, Thomas. I am not sure which temp thermo I bought... ordered through Dan. I think it will be OK, but I am keeping my eye on it for the next few days.
fan clutch

My gauge has four lines. one at cold, one just before the red zone, and two in between. My cruiser always ran just above the second line until I replaced the radiator and thermostat(also C-Dan) at which point it ran just below the third line.
After driving three months, it is back down to just above the second line.
If you are running above the third line up to the line just before the red zone, then I would check the fan clutch and make sure it is gaining resistance as the engine heats up. If its not it is like a slipping belt.
This discussion is not very useful (not trying to put anyone down, of course).
The Toyota temp gages are inherently inaccurate, and two will not give the same reading at the same temperature.
The only way to get an accurate reading is to put an aftermarket gage with a sensor on the engine side of the radiator. Normal operating temperature is 82 to 90 degrees celsius (180 to 195 Fahrenheit).
The two thermostats available open either at 82 celsius (180F) or at 88 Celsius (190F), and Dan can get either one for you. The thermostat is the same for 2F and 3FE, or 3B and 2H engines.
swap in a 180 degree 'stat and see how it does. Most autoparts stores seem to stock it. For some reason its about 10-15 dollars more than the 190????
I recently replaced my thermostat (and both gaskets) and in the process I found out a stock thermostat opens at 190--or 195, can't quite remember-- since I drive in temps above 110 degrees during the summer, I ended up replacing mine with a 180 degree one. The cruiser now runs between 1/3 and 1/2 mark. Oh, and it was about 15 bucks at O'reilys...

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