Thread: Fan trouble

For the crank nut I wedged a breaker bar on the ground below, then cranked the engine. the power of the crank then undid the nut.

Believe the fan hub is left hand thread?

Originally Posted by olblu

I can't crack the nut on the viscous fan hub and i've already bent my largest screwdriver trying. My vehicle is a 96 3.9 v8i. I need to replace the waterpump.
I have the right spanner for the nut, but holding the pully in place is a problem.
Any suggestions would be appreciated.

Being a 96 V8i it will have the serp belt on it & the thread for those are standard RH thread,
place the spanner at 12 oclock on the nut and give it a good belt with a heavy hammer, it will crack the thread after a few good belts.

The earlier engines with the V type belts have a LH thread.

The suggested sharp tap of the spanner with the heavy hammer works. You could also get an assistant to told the hub with a 10mm ring spanner over one of the hub bolts to reduce it's tendency to slip.

Thanks people I finally cracked it by wedging my bent screwdriver in the pully and giving it a dozen or so belts with a hammer.Its only taken me a week of trying to do it.

The dreaded Loctite on the fan hub.
FEV had the same thing on his and it took us about an hour to get it off.
Why on earth do mechanics do this?
I just tap mine once while installing and use anti seize and mine has never gone spinning of to the horizen.
The engine rotation keeps em on FCS.
Regards Philip A

My 88RR threw a fan blade just south of Coober Pedy in 2001 when I kicked down to overtake a road train. I spent 2 hours at the side of the road trying to undo the fan hub- no amount of wedging, hitting, levering or cursing made any impression on it. Drove the rest of the trip home to Gippsland with 10 blades on an 11-blade fan and the resulting vibration.
I now carry a tool I fabricated for the purpose; it has 2 legs of 6x20mm (iirc) flat bar, one with a hole near the end, welded to a short piece of pipe. The legs are in a V, such that when the hole in one leg is hooked over one of the fan hub bolt heads, the end of the other leg sits against another fan hub bolt head. My bottle jack handle serves as a handle for this tool when inserted into the short piece of pipe to which the legs are welded.
If I ever regain the ability to post photos, I'll put up one of this tool.
No more hitting and cursing, and the tool is reversible for LH or RH threads.
Like an oil filter wrench, this tool is used for removal only and never for refitting the hub.

Originally Posted by POD

My 88RR threw a fan blade just south of Coober Pedy in 2001 when I kicked down to overtake a road train. I spent 2 hours at the side of the road trying to undo the fan hub- no amount of wedging, hitting, levering or cursing made any impression on it. Drove the rest of the trip home to Gippsland with 10 blades on an 11-blade fan and the resulting vibration.
I now carry a tool I fabricated for the purpose; it has 2 legs of 6x20mm (iirc) flat bar, one with a hole near the end, welded to a short piece of pipe. The legs are in a V, such that when the hole in one leg is hooked over one of the fan hub bolt heads, the end of the other leg sits against another fan hub bolt head. My bottle jack handle serves as a handle for this tool when inserted into the short piece of pipe to which the legs are welded.
If I ever regain the ability to post photos, I'll put up one of this tool.
No more hitting and cursing, and the tool is reversible for LH or RH threads.
Like an oil filter wrench, this tool is used for removal only and never for refitting the hub.

A mate did a similar thing to his 300TDI Disco, we just cut off the opposite blade with a pair of tinsnips and carried on as if nothing had happened until he ordered another blade ( done that a lot of times with old belt drive refrigeration systems to keep them going until replacement parts were found)

Originally Posted by ezyrama

A mate did a similar thing to his 300TDI Disco, we just cut off the opposite blade with a pair of tinsnips and carried on as if nothing had happened until he ordered another blade ( done that a lot of times with old belt drive refrigeration systems to keep them going until replacement parts were found)

Unfortunately there is no 'opposite' blade on an 11-bladed fan! I already had the hacksaw out when I counted the blades. The blades on these fans also have asymmetric spacing to reduce noise.

Could have been worse though, the blade only damaged the shroud on it's way out. I had one let go on a dyno another time and it holed the radiator.