Reverse rotation fan "Left hand thread"

[Noiseydiesel]

'94 idi Turbo, crewcab dually and looking at the top of the radiator shroud, it is stamped "Left hand thread"
Then looking at the fan blade, it actually appears to rotate counter clockwise to pull air through the radiator.
Think it might be possible that a "standard Rotation" fan clutch might have a slight contribution to a lack of cooling running over the mountain (Mt Hood) and overheating?

Duh!
My brain hurts when I use it and I like a pain free existence.
I feel so smart for finally looking.
Ouch! Ouch! Ouch!
My head hurts.

 

[snicklas]

That is the thread that holds the fan clutch to the water pump, not the direction the fan turns. It’s left handed, so that while the engine is running the spin of the engine into the clutch is “tightening” the threads all the time.....

 

[Noiseydiesel]

True enough but generally the left hand thread means you really should at rotation direction.
So I now have a new brass/copper rad and waiting for the reverse rotation fan clutch to show up.
Now the wife say's she wishes the truck was running for next Monday.
Uh... waiting for a fan clutch dear....
Not gonna have it road ready Monday.

 

[franklin2]

The way you can check your thinking, see what direction the waterpump turns. Then pretend you are grabbing the fan and stopping it with the engine still turning. That should tighten it on the threads. The standard setup does use lefthand threads.

 

[Noiseydiesel]

". . . standard setup does use lefthand threads."
Too many years wrenching on too many vehicles to pay too much attention to a whole lot of selected groups of vehicles. I do remember once upon a time long, long ago, putting a water pump onto a Ford diesel. Reading the Ford directions it stated, "Ensure there no skew to the Sheave Line.
Took me a while to figure that one out. Turned out I did it before figuring out what the engineer meant by writing that.
I looked at the delivery date on the fan clutch. It can be ready Monday. Yes dear.
Not gonna tell her that. Yet.

 

[gandalf]

That is the thread that holds the fan clutch to the water pump, not the direction the fan turns. It’s left handed, so that while the engine is running the spin of the engine into the clutch is “tightening” the threads all the time.....

This is one of the primary reasons these are so difficult to remove. That difficulty is two part: the design will cause the fan assembly to tighten with use, and when we remove the fan we frequently forget that it has that reverse thread and tighten it beyond belief before we figure it out.

People have been known to have their fan fall off with the engine running. Apparently they did not tighten it enough (as I recall it has a high torque spec anyway) when they installed it. When it falls off it usually chews the crap out of the radiator. Those people are very unhappy campers.

 

[IDIBRONCO]

waiting for the reverse rotation fan clutch to show up

The Ford IDI fan clutches are all the same rotation. There isn't one made for our engines that rotates the other direction.

 

[Fordman1920032003]

i put a dab of blue loc-tite on mine when i put it on. Ive seen the spin off upon shutting the engine off.

 

[Randy Bush]

Your blades should be face this way, anything else is wrong.

You must be registered for see images attach

Sent from my SM-A115A using Tapatalk

 

[Ky85]

xc_hide_links_from_guests_guests_error_hide_media

Dont tell her, just pull into the driveway and honk the horn when its ready!

I just got done doing a fan clutch..and yes I may have tightened it some before my Check Brain light came on too!!