Fan clutch elimination- 100% engaged, what would happen?

What would happen if I simply ran bolts through my fan clutch housing so it turns 100% of the time at all times? Why do we really need a fan clutch?

(I know these are dumb questions but I'm so fed up I may try that now)

 

It's their for energy conservation and power saving. Back in the really old days we would replace bad ones on running warm rides with what was called a flex fan. No clutch, but the blades would change pitch (and air draw) with RPM changes. They worked, but noisy sometimes.

If it has tested bad, replacing it with a fresh unit is likely a better idea.

 

unless you ran it till it went flat but then its guzzling gas like crazy any how...I used to have a flex fan on my old camaro, It was noisy though I agree...

 

@kayakingguy here's a helpful article http://www.aa1car.com/library/cooling_fan_clutch.htm

 

Interesting. I'm still not sure what exactly we need a fan clutch for? Seems like a lot of complexity for... ?

 

I had an fj60 that the fan clutch was stuck in the on position. It was designed to come on only when the coils got hot enough to lock the blades in the turning position. It is supposed to be off when there is sufficient airflow when up to speed. If it stays on at speed it draws a lot of power from the engine and is very loud. It was very annoying until I replaced it.

 

Read the link I gave you above. It actually matches (in more detail) what I wrote. Which means the memory is hitting on at least 7 of 8 tonight.

It tells what/why and how to test.

Never replace or alter something like this until you've verified it's bad.

 

I can't tell at this point what's going on. I can't tell how loose it really is. I'm going to make it fixed, and if that eliminates the overheating then I'll replace it, if not, oh well... I'm ready to part the truck out anyway.

 

You can't do the simple spin test the article describes?

 

The viscous fan clutch is hardly complex, in fact it is a quite remarkably simple solution to de-powering the cooling fan when it is not needed, one that has been used for well over 30 years. Additionally it is more efficient than converting mechanical rotational energy to electricity, and then back to mechanical rotary power with an electric fan motor.

The viscous clutch has just two moving parts (three if you count the bi-metal "valve" disc):



You can but a new one from RockAuto for $50 or so...

 

Under what conditions are you experiencing overheating? If it is at any speed over 20 to 25 mph the fan clutch is not the problem.

What year is your truck, how many miles, what's the climate like where you live?

 

It doesn't spin much when turned with the engine stopped. It also takes a fair amount of resistance to stop the fan when turning...

If it isn't the fan clutch then I'm out of ideas other than the head though, or messing with replacing the brand new water pump and thermostat again... A head is a bit more of a project than I'm ready to take on due to schedule.

 

96 2.7, around 170k miles now, and it's very hot/humid, but the truck never passed the halfway mark on the temp gauge before regardless of ambient temp.

 

It is rather ingenious, I'll give you that... coefficient of friction and all of that. Not sure it's the problem at this point, versus the head, versus the new water pump and new thermostat (which I tested and was good before I put it in)... This is one of those times where another pair of eyes would help, but there's nothing but commercial shops which would kill me on labor and I don't trust around here... we're talking about a truck that has no value except transportation. No AC, body damage, leaking load sensing proportioning valve, valve cover gasket leak... removed the AC compressor and AC heat exchanger already... even for parts this truck has limited value.

 

Under what conditions is the temperature gauge rising what seems like too far; idling, accelerating, at speed?

Does the gauge keep rising 'til the truck overheats or does it stabilise? It could also be a failing/shifting value temperature sensor...

 

It rises at highway speed if I stay at a stable 70, for example, to about 5/8 of the way up, then if I feather the clutch and rev the engine it goes back down.

after highway driving if I stop or idle with the engine running it's getting up to about 3/4 of the way up and stabilizing, then will drop after revving the engine a few times...

it doesn't seem to overheat if the engine rpms are varying.

 

Thermostats are only loosely "calibrated", simply changing one out could alter the gauge reading one an older truck with a real coolant temperature gauge--as opposed to the heavily damped "idiot" gauges used on newer vehicles.

Does the temperature eventually stabilise?

 

It stabilizes, but each time I drive the truck has been stabilizing at a higher temperature. I also thought I smelled antifreeze a few times even though there are no external leaks... maybe it's a cracked head all along but I haven't had time or tools to do a compression test yet... Might be selling this truck for parts.

 

I would suspect a partially clogged radiator, the higher revs cause the water pump to move more water making the "unclogged" portion of the radiator temporarily more efficient...

 

Could it be clogged even though I just put it in a month ago and flushed the block?