running hot

WornTired

Well-known member
I'm having problems running hot again. I was thinking of either adding a reserve to the radiator or possibly recessing the radiator a couple of inches and adding a flexfan or similar on. I've got a 200BB w/ an electric fan right now. Any help or suggestions?
 
What car do you own? What is your idle speed set to? Do you know what temperature your current thermostat is set to open (i.e., 180*, 185*, etc.)? What is your radiator fluid mixture (how much fluid vs. water)? And most importantly, where do you live? :wink:


-Chris
 
Posted: Fri Jan 23, 2004 2:03 pm Post subject:

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What car do you own? What is your idle speed set to? Do you know what temperature your current thermostat is set to open (i.e., 180*, 185*, etc.)? What is your radiator fluid mixture (how much fluid vs. water)? And most importantly, where do you live?


Its a 64 falcon. Idle is set fairly low w/ the thermo at 180. I followed the mix on the bottle. I live Corpus Christi, Tx. Thanks.
 
how old is your radiator?

How old is your water pump?

Have you verified your temp with a mechanical gauge, or are you going by the dash gauge?

First, I would get a mechanical gauge and see what the temp is really running at. Get one of the cheap ones at Autozone or the like.

If you hav an old waterpump or radiator (or hoses), I'd start there. I put a new 3-row radiator in, and my car never overheats any more.

Slade
 
Its got new everything and consistently runs above 200 if I let it. But it does have the 3 row radiator and all new hoses and a water pump and the temp gauge.
 
Some things to check:
*Are you hot as indicated by the gauge or are you really boiling over. Verify that it isn't the gauges.
*Gauges may not be accurate, and replacement temperature senders are often not calibrated correctly to work with the old gauges.
*Check thermostat operation in a pan of boiling water.
*Radiator cap must be sealing correctly or it will not prevent it from boiling over. New caps have been known to relieve at too low of a setting.
*Make sure your timing and vacuum advance is functioning correctly. Retarded timing will cause engine to overheat quickly.
*Make sure the air is pruged out of the system when filling with coolant.
 
I'll also add in that the aluminum water pumps are no where near as good as the cast ones are. Take a look at the impellers on the aluminum ones, I changed to the cast one and noticed a decrease in the water temps significantly. The aluminum stamped pump's impellers are a 1/4" away from the housing and my feeling is that they can cause cavitation. Another issue, maybe not yours if the block was rebuilt and tanked, is a buildup of crap in the water passages in the block holding heat transfer to a minimum. Another issue mentioned is the timing which a lot of problems with over heating is do to the dizzy vacuum diaphram going south and not advancing at speed, especialy on the older dizzy without mechanical advance. Just a few more things to think about.

Steve
 
I have the opposite problem, I can't get mine to warm up. A piece of cardboard is doing it for me now.
Now then, if you had a small crack in your head it could cause your coolant temp to go up, but if that were the case, your coolant would be pumping out of your radiator to the rythm of the cylinder. I am a mechanic in the Air Force. We had a Hummer with a cracked head. I didn't know it was cracked at the time, I was treating it as if it had a overheating problem, there was no coolant in the oil. The coolant would gush, then stop, then gush, till there was no coolant left in the system.
If you were to remove your thermstat, your motor shouldn't overheat, but then it would be a bear to get it to warm up.
I would look at a possible blockage in the motor. Pull the radiator cap and check for fluid flow.
 
Worn;
What is your timing set at static?
If it is retarded or your points' dwell is too short, it can cause heating.
If it is advanced too far or your points' dwell is too short, this can also cause heating.

Most 200 engines should be set about 6-8 degrees static advance, unless it is a smog-controlled engine with EGR, then set at 10 degrees static.
 
I haven't checked the timing in a few months, but I did have set at 8. I'll get back there and check friday I guess. The gauges seem to be working fine as the fan kicks in at the temp set with the gauge reading right. I had some problems with the vacuum before so I'll check that again and see if anything deteriorated. Thanks for all y'alls help.
 
On mine the most common cause of overheating when the cooling system checked out fine was the wrong timing.

I would check the timing and see if you are off, if it is too far either way it will run warm...

one thing you can do is pull the radiator cap when the car is cold, start the engine and let it warm up, put a candy thermometer in the coolant and watch the radiator as the car warms up, once the thermostat opens the hot coolant will come into the radiator, watch as the thermostat starts to open more and more and note the temps of the coolant coming out...

I agree on getting a mechanical gauge from Autozone and starting there, that will give you the best information on what is going on.

If you verify timing and verify good coolant flow, then pull the thermostat and put it in a pan of water on the stove and make sure it opens at 180... I have bought several therms that were brand new and bad, now I test them before I install them...
 
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