Cooling fan fell off

[egleaves]

bd, you are very thorough.

I unbolted the stub shaft from the water pump flange.  All three bolts were there and tight.....kidding! All four bolts were tight.

I also removed the bolts that hold the fan to the clutch and again, all four bolts present and tight. So far everything aside from the point of failure has felt tight and snug, but I haven't tried to wiggle the water pump yet.

[Irish_Alley]

might be a stupid question but is that one of those reverse rotation water pumps? if it is and they used your original fan it might have been turning backwards

[bd]

Irish makes a valid point.  When you get a chance, post a pic of the belt configuration and routing.  It's important information to ensure the correct rotation replacement clutch and fan.

[Irish_Alley]

its a stretch but if the dealer installed the wrong fan on their own without informing you its the wrong one and had you sign off, they should be responsible for it. but the cost of a rad and fan will be far less than taking them to court

[egleaves]

Yeah, I could probably prove GM to be at fault for something, but it would cost me more to go after them than to just eat the cost of parts.

I picked up a radiator today and going to install it tomorrow. I haven't bought a new fan yet so I'll verify the rotation tomorrow also.

Thanks for the ideas and input.

[roundhouse]

I've worked on a lot lot of cars in my life

Never seen that problem



Sent from my iPhone using Tapatalk

[egleaves]

I drove myself to work today! 

I verified the water pump rotates counter clockwise and learned the old fan was rotating the right way, but I haven't been able to verify which way my exploding clutch was supposed to rotate.

It appears that my original engine was standard rotation (CW), and my new engine is CCW but the dealership used my original fan on the new install.  They must have installed the fan backwards to get the rotation right!  Can you do that?  I know fans have a direction, but what are the ramifications of installing a fan backwards as long as its blowing air the right direction?

What if the exploding clutch was a CW rotation unit that has been running on a CCW water pump with a CW fan installed backwards?

[egleaves]

Also, is there any way to verify the correct rotation of the old clutch?  There are no helpful markings on the outside.

[bd]

Generally, the fan hub rolls gently forward at its circumference toward the clutch body when properly installed.  Automotive cooling fans are designed to rotate in one direction only.  They won't perform correctly if reversed.  The old clutch may have a part number (or partial number) stamped on it.

[Irish_Alley]

looking at your fan picture of the broken clutch it looks like its on correctly and is a ccw rotation fan which is odd cause your OEM fan should have been CW rotation and theres no way to install it backwards like bd said

[egleaves]

I've been trying to educate myself on exactly how the fan clutch works so that I can understand how it might fail.  None of the "tutorials", or "how-does-blank-work" articles that I have found really go into what is happening on the inside.  I get the whole concept of the bi-metallic spring opening a valve and allowing fluid to flow, but does this mechanism work more like a plate type clutch that relies on face-to-face contact, or more like a torque converter with vanes?  I'm guessing more like a torque converter with some sort of vanes to transfer the forces from one half to the other.  Then I'm wondering if those vanes are directional.  Then I'm wondering if it was running it backwards for a year and it wore out prematurely.

Anyone ever been inside of a thermostatic fan clutch far enough to see whats going on?

[Irish_Alley]

Then I'm wondering if it was running it backwards for a year and it wore out prematurely.

this is what im thinking. most of us havnt seen this type of issue i dont think weve dealt with a clutch being incorrectly installed for the rotation. but im still confused on how the fan is correctly installed when it shouldnt have been if they reused your old fan. was your old motor V-belt or serpentine?

[egleaves]

this is what im thinking. most of us havnt seen this type of issue i dont think weve dealt with a clutch being incorrectly installed for the rotation. but im still confused on how the fan is correctly installed when it shouldn't have been if they reused your old fan. was your old motor V-belt or serpentine?

The old engine was a typical V-belt.  New engine is serpentine.

Something I've run into with this truck is that it is apparently some sort of "half-year" model.  Last winter I went to replace the blower motor with a part for a '74 only to find (the hard way) that I needed a blower from a '75.  I'm told I might run into more parts like that in the future.  I just looked up a water pump for a '75 and it is still listed as standard rotation.

The only thing I can figure it that they turn the fan blades around backwards, which would move air in the right direction, but at what cost?

[Irish_Alley]

afaik they didnt do the reverse flow till they went to serpentine system and if the pulley was smooth it would turn the opposite way of the crank which was 88+. the blades cant be turned cause the fan housing is bent to form around the clutch. im sure you could flip it but this would put the blades a couple inches towards the engine and into the belts/pulleys

[bd]

...Anyone ever been inside of a thermostatic fan clutch far enough to see whats going on?

See PROPER WAY TO TELL IF CLUTCH FAN IS WORKING?.

Are you sure the dealer didn't install a new fan blade and reuse the old viscous clutch?  It would surprise if a dealer made that mistake, but dumber things have happened.  Inspect the old fan clutch for any numbers that might be useful in identifying it.

You might find the vehicle production date imprinted on the SPID or door plate.