Follow up to Head Gasket in a bottle repair and a question...? (Ray O et al, listen up!)

Obviously, a lot. If a brake were slowing decreasing the gas mileage that much, it would be glowing red hot by the time you drove a few miles. How long did you have a power loss? But I wonder if somehow the problem caused the sensors to be messed up or something and that caused the loss of power and poor mileage.

The other thing this type of seizure can cause is the crankshaft to be pulled out of place (like pulled being pulled up to one side) because of the extra torque needed. This could damage the bearings. I somehow remember this ruining a few engines in the old days.

Jeff

If the AC clutch seized then you'd be running AC during winter, right? That probably won't be very good for the compressor if the refrigerant couldn't evaporate. Your compressor is going to get liquid slugged. Otherwise I don't know why the belt would burn unless the compressor is generating a lot of resistance to turning.

When it is warmer out (say around 10 C or 50 F), the compressor often comes on when the vent is set to the defog position to help dry the windshield. This also helps keep the seals moist.

I have never heard of a problem with A/C with getting the refrigerant slugged.

Jeff

The AC idler pulley was seized, not the AC clutch.

The AC clutch was one of the first things I checked on the car. It seems to be operating normally: locking when the AC is turned on and free-wheeling when off. It was the idler bearing that seized and started burning the belt.

That's not good!

Luckily, not only was the bearing on the way out, but the tensioner also was stuck at less-than full tension, so the belt was slightly slipping anyway.

The AC runs often in the winter - every time one uses one's Defrost setting. It uses the AC to dry out the air. Tomes

Also assuming things are working correctly (always a risky assumption) The AC shouldn't have to do much work when the air is already cold and dry. That is, the load on the engine is significantly less than when the weather is hot and damp.

-jim

This car is older than that...

The earliest factory air conditioning systems (circa 1940 Packard) did not have a compressor clutch, the compressor ran whenever the engine was running. (To "turn off" the AC during the winter one would have to remove the compressor drive belt.)

The car is not *THAT* old... ;)

I had a Rambler that had a 'Desert Only' switch. As near as I could tell, the idea was to use the A/C to cool the heater core to assist in engine cooling!

weird

Carl

Older than what? My little brain here is trying to tell me that the old

1971 Pontiac Safari wagon we had did this. When did using AC for defrost start then? Tomes

I don't know what the desert mode did, but that wasn't it. Any heat removed from the heater core by the a/c would be dumped by the condenser plus the additional load on the engine from running the compressor.

Steve B.

The Weather Eye in my Hornet has the "Desert Only" AC setting. The purpose is to provide maximum cooling in a high-heat, low-humidity environment (i.e., the desert). The compressor is run continuously on this setting, which would lead to evaporator icing if the humidity is high. (Perhaps the old Packard system did not get cold enough for this to be a problem.)