that word fully , sells many fans after market and not one site anywhere states, the actual drag. (lots of lies, no proof) and no suzuki spec either (other than cut in temps)
yes the grease in side is viscus when cold and does use some energy, its small. on a therm fan clutch. The question is , how much is it. Id say its not important
but on the ecommodder.com forum they'd have a hissy fit and show all improvements all add up. ok. good. they do add, and after 1 year, sure, a gallon of fuel>? what? what is payback. time.. if any. (fan plus labor costs)
bet , you could not measure any difference at all. (odometer ? and island pump gauge gallons?.)
if you did?,that be inside the normal variance of all tests. ( the island pump never shuts off same time for any car so the MPG will very more than the parasitic loss by 10 fold.)
but you could make a tiny dyno (or just a emoter and and an ammeter /volt meter to measure watts lost. at the fan.
its and act of faith.
put in a 200f thermostat and get 1/2mpg.? (raises efficiency)
i think my test is no good.
your spinning air, and the air slips...... physics,,,,, dang.....
the loss is in the coupling (heat) and the heating effects of spinning air. (not much and real hard to measure)
so the bench test would be , replace engine with a DC motor. (bench test is hard with shroud and rad in place.)_
and measure motor current at idle (cant do faster because you dont have free air flowing on the bench)
bingo, rubber meets road.... emotor spins clutch>>> clutch spins real fan in real shroud)
when driving you get free air past RAD the cancels most the parasitic drag (complex huh) the efan dont get rid if the water pump.(belts pulley,etc, all are very wasteful)
in military tests (have link), they got rid off all belts and used emotors and switches to control (with processor) to control it all , on huge engines. or 10% gain.
here is just a fan. swap.
Correct me if I'm wrong but the mechanical fan never fully disengages...
Yes, it is constantly running. It operates at the same speed as the water pump shaft until the air temp at the shaft exceeds 130F, at which time it will revolve at 3100 rpm always (clutch slipping), independent of the water pump shaft.
Yes, but is that not the reason for the fan clutch, to reduce the amount of horsepower that the fan is drawing? The fan is locked to the shaft at low/idle speed, when horsepower is not needed. As the engine speeds up, and horsepower is wanted, the clutch slips so that not as much horsepower is being used. That being said, the fan will still rotate at about 3100 rpm, with the clutch slipped. A fan with the fan clutch will use less hp than a system that doesn't have the clutch.
I think another application for the electric fan is to be able to turn it off when you are in mud or water, so that the constant turning of the fan isn't throwing muck all over the engine and components.
that is bunk
at red lights, all summer long, needed.
going up a very steep hill like grape vine or rocky's or I80 to Tahoe. (slow)
needed in the hot summer. (USA southern states?)
and any time cooling issues come up. or carrying a load...
like good ol' limphome ,hitting the proverbial fan (double pun) grin (dumps huge heat load on the RAD it does)
please dont get hurt testing that fan, be beyond arms length for any wild testing.
the base ball bat test.
the throw rag test.
never hands. never dangle rag test.
in a car (have 2 now) with electric fan its obvious when it comes on
not so on the suzuki, not at all, (unless it fails.)
The AutoGuide.com network consists of the largest network of enthusiast-owned enthusiast-operated automotive communities.
AutoGuide.com provides the latest car reviews, auto show coverage, new car prices, and automotive news. The AutoGuide network operates more than 100 automotive forums where our users consult peers for shopping information and advice, and share opinions as a community.