Fan Clutch & A/C part 2
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Fan Clutch & A/C part 2
I posted a few weeks ago how I thought my fan clutch was stuck...well, only if I run the A/C does it stay on constantly even on the freeway..but if I don't run the A/C it won't even run. Is there a bypass I can do to cut it off or come on very selectively? Such a drag when I run the A/C and my mileage sucks...
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That fan is there for the sole purpose of cooling your condenser when your a/c is on. Its not the fan that is robbing power. When your a/c is on, the compressor is being turned by the crank shaft via a belt. That where your losing your power. Thats why high end drag cars run an electric water pump, no power steering and alternator disconnects. Its for less power loss. Thats if they even run coolant
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Does it really take rocket science to explain why a fan running can pull horsepower from the engine?
The fan roars and you lose power when you turn the AC off because it runs until the pressure in the AC high-pressure side drops enough so the fan is no longer needed. In the mean time, it draws power from the electrical system of the vehicle and the alternator controls that so... more power draw means more alternator output is required which in turn means more drag on the engine.
Common sense, not rocket science.
The fan roars and you lose power when you turn the AC off because it runs until the pressure in the AC high-pressure side drops enough so the fan is no longer needed. In the mean time, it draws power from the electrical system of the vehicle and the alternator controls that so... more power draw means more alternator output is required which in turn means more drag on the engine.
Common sense, not rocket science.
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Does it really take rocket science to explain why a fan running can pull horsepower from the engine?
The fan roars and you lose power when you turn the AC off because it runs until the pressure in the AC high-pressure side drops enough so the fan is no longer needed. In the mean time, it draws power from the electrical system of the vehicle and the alternator controls that so... more power draw means more alternator output is required which in turn means more drag on the engine.
Common sense, not rocket science.
The fan roars and you lose power when you turn the AC off because it runs until the pressure in the AC high-pressure side drops enough so the fan is no longer needed. In the mean time, it draws power from the electrical system of the vehicle and the alternator controls that so... more power draw means more alternator output is required which in turn means more drag on the engine.
Common sense, not rocket science.
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Best I can suggest is hook a high-pressure a/c gauge to the system and see how the a/c pressure is while the fan runs. It may be a delay built into the fan switch that keeps it running for X minutes for all I know.
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Actually not finding a condenser fan at all on my truck, what I am hearing is the main engine fan in fact. Like maybe it didn't come with A/C from the factory and someone added it later...i don't know, it looks factory though.
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Sounds normal, don't think truck has the problem.
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Yeah I couldn't tell at first, I'd rather have a smaller electric fan running than the engine fan taking all the power and sucking the mileage off. You would think a 4 cyl engine like these would have 2 fans as to reduce drag.
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