JD 40 Fan Belt Replacement

[saxnbees]

I need to replace the fan and generator belts on my JD model 40 tractor but cannot seem to find much information on the net. I have removed the sheet metal exposing the engine and radiator areas. I have also moved the coil and generator out of the way. I have obtained a 1 7/16 wrench that fits the large nut on the back of the fan assembly. However, I have not been successful in loosening the large nut. I have been applying penetrating oil and tried hitting the end of wrench with a rubber mallet but with no luck so far.

So, before I break something, I am asking for advice.

The first question I have is the thread on the large nut...is it a left hand thread? Or am I actually making the nut tighter unknowingly. Is there a better way to loosen the nut?

Beyond that, can you impart any suggestions or advice on the best way to remove and replace the belts once I get the nut loose? There is not a lot of working room in there and any suggestions are welcom.

Thanks.

 

[beenthere]

Can you post a photo or two of the area ? Been awhile since seeing the two-cyl 420 but have a faint memory of changing the fan belt. Maybe a pic or two will refresh that memory.
Member Tx Jim has good experience and may see your post too, as well as others.

This video help any ?

 

[saxnbees]

Thanks for the video but my problem concerns the large nut at the back of the fan blade assembly. Here's a couple of pictures of the area.

 

[beenthere]

Maybe easier to remove that fan bracket (key#4) that the nut is attached to for better leverage (heat ? ).
Suspect that large nut is regular rh thread.

 

[saxnbees]

Thought about that possibility but temporarily rejected the idea because it looks like some other stuff is bolted to it and it will be tough to get the whole assembly out of the space. Thanks for the idea...I may eventually come back to it.

 

[oldtimer 66]

My neighbor has a impact tool/ muffler gun with a special driver that he uses to remove clutch type fans, It impacts against a standard wrench. and or the set of wrenches that came with the tool.

Here is a tool from amazon https://www.amazon.com/BETOOLL-Pneu...cphy=9006414&hvtargid=pla-2281435179498&psc=1

 

[saxnbees]

Interesting. Thanks for the suggestion.

 

[DJ54]

Is it necessary to remove the fan at all..?? Try slipping the belt over one fan blade at a time. Should be enough room for it the belt to fit between the radiator and fan if you loosen the fan to adjust it.

 

[saxnbees]

The problem is that the nut in question is what loosens the fan assembly to adjust the tension on the fan belt. To this point, I have been slightly successful in that I can now move the assembly up and down a bit. If I can move it enough to get the belts on and off as you suggest, I could consider a means of pushing up on the nut to adjust the fan belt tension, maybe a wooden wedge? or a piece of steel with a couple of adjustment bolts?

 

[DJ54]

You may be able to put a pry bar on the washer behind the nut and slightly pry upwards and still be able to turn the nut.