Posted by Charlie on March 31, 1999 at 22:09:27:
In Reply to: Any opinions regarding installing either a fan clutch? posted by Gary on March 31, 1999 at 06:36:09:
The power consumption of a boat prop in water is proportional to the 2.5 power of the rpm. They talk a lot about power consumption of fans, like "25-30HP", etc. But if, for example, it is 30HP at 5000 RPM, absolute max rpm for a gasoline US truck engine, then at half the rpm, 2500rpm, that'd be only about 5.4HP. At 1700 rpm that'd be less than 2HP. Re fan clutches: on my F350 off-road minimotorhome, my fan clutch failed and it overheated climbing a hill near Denali on a 70 degree day. I replaced it with a solid connection. At highway speed, 70 mph, I'm running 23-2400 rpm. I suspect the fan is drawing <10HP. I pay for it, but overheating is not a nice thing. I would recommend, for a W500, a heavy truck with a relatively small motor for the weight (?318 or 360?), probable low annual mileage, probable mostly low sppeds, with significant low rpm low speed off-road use,, a solid fan non-clutch.
Charlie