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Today I was driving to a different town when I noticed the temp starting to climb so I pulled into a garage. I was afraid the waterpump was giving it up, or a hose, or the themostat, or the fan clutch...or whatever!
Still, I thought I'd get more warning to a problem...no puddles under the 78, and I look regularly!

Anyhow, cheapest and easiest first...we checked the radiator fluid level, and it was about a gallon low! Filled it up and the 78 cooled back to normal. Inspecting the cap, the gasket/seal was cracked. Could this have explained the loss of that much fluid over time? Old rad. cap was rated @ 13lbs, replaced with 16lbs.

Anyhow, I need advice about the fan clutch...

I am under the impression that a fan clutch is working properly when it has free-spin to it when cold, so it spins easily and has some resistance when hot, but will still turn by hand. I was told today, by a shop customer, that when I turn off the car, the fan should stop with no spin at all. Mine spins a little...which is correct?

Any thoughts on flex-fans? Electric fans?
78 usually runs just under 200 if I drive at speed limit. It will run a bit hotter if I fly along...thermostat is a 190.

The fan should not be locked up even when the engine is at normal operating temperature, there should however be much more resistence than when partialy warm or cold.

flex & elec fans

Sorry bout you probs... although my experience w/ flex & elec fans is w/ other cars: flex fans are noisy as all get out...elec fans work fine if you've got the right size(s)/duals but they're are a lot of trouble to install properly with sensors, relays,etc. Replace the cap and tstat now...Check your overflow bottle/jar/can (slip it out if not too much trouble) for leaks in it or in hose going to it from radiator now... then go straight to a reputable radiator shop/garage and have them pressure test your system. It was rather hot in the Southeast today...hit 91 here... Keep things in context. Fan clutches aren't so expensive nor difficult to change out. Let us know.
Now that you've filled the cooling system to the proper level and installed the right pressure cap, your cooling system, incl. that fan clutch, is working properly.

The only change I'd make is a 180 degree thermostat.

I will call around for a radiator shop tomorrow. Thanks for the advice..I'll get a 180 tstat, have the cool system pressure checked (I did check the overflow tank and hose-its good) and it appears my fan clutch is working properly.
Thanks for the help! :w


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