# stubborn pulley on sickle mower



## v.rad (Jul 16, 2019)

Hi,
I would appriciate any help with my sickle mower repair. The clutch cable got torn, and to replace it I have to go behind this pulley that transfers power from the engine to the wheels and the sickle bar. Not a very good design appearantly, but no other way to reach this cable. It's the bottom pulley in the pictures that needs be removed. It is two parts, I removed the bigger alumium part that was attached with 4 regular screws, and tried to pull the smaller steel or alloy part with a pulley remover but it didn't want to come off in fact it got bent slightly :surprise:
In the middle there is a key whole so I assumed the pulley was not threaded on the shaft. 

any opinions? I would like to remove it and do no more damage to the machine... thanks!


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## finaprint (Jan 29, 2006)

Are you sure that pulley hub is not one of the type that pulls the back up tight to grip the shaft? Meaning once bolts are removed you lightly tap on the hub INWARD to knock it loose. A puller would simply make it lock tighter in that case. 

Be careful, I'm not sure, please don't damage things based on what I said but I used to deal with that type locking hub all the time on printing equipment. That pulley hub looks similar.


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## v.rad (Jul 16, 2019)

Thanks, that sounds very interesting. I don't know if it could be a pulley like those you described, but in that case after it got loose, would it still come off outward? It can not be taken off inwards because of the machine housing and lack of space.

Do you know what that kind of pulley is called?


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## paulr44 (Oct 14, 2008)

finaprint said:


> Are you sure that pulley hub is not one of the type that pulls the back up tight to grip the shaft? Meaning once bolts are removed you lightly tap on the hub INWARD to knock it loose. A puller would simply make it lock tighter in that case.
> 
> Be careful, I'm not sure, please don't damage things based on what I said but I used to deal with that type locking hub all the time on printing equipment. That pulley hub looks similar.


The locking hubs you speak of have a noticeable split, and if it was one we would expect to see bosses in that upper pulley, yes?

It does appear the cast-iron hub needs to come off first, since it has bosses (bolt holes) perhaps you could latch onto it with a slide-hammer. I can tell you _Open and Shut_ by Lawson is a good loosening penetrating spray, if you give it a little time to work.

Also, I bought a Snap-On "cotter pin" removal tool decades ago, but use it for bearing races and the like. I break it, they give me a new tip. Snap-On's site is down right now, here's link so you can see what it look like, pair it with decent hammer and it'll be worth having in your tool box.

Purchase SNAP ON Cotter Pin & Seal Puller 10" Long - S9094B motorcycle in Houston, Texas, US, for US $39.99


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## finaprint (Jan 29, 2006)

Yes, the center insert has a noticeable split in it IIRC, been a long time since I dealt with them. Printing equipment drives mainly. The hubs only have to move inwards a few thousandths of an inch before they break free and come loose, they don't have to go far normally.

Further thinking seems to be that they have a separate ring on the back the screws thread into and the ring pulls up on an angle to produce the clamping effect needed to lock it all down, use a screwdriver on the backside ring to pop it loose if that is so. Then the hub comes free that way too.

On even more thinking the front hub does not necessarily need a big split if the back of it had tongues that can squeeze closer to clamp when back ring is pulled up tight. 

Like I say, it's been a long time and I've seen so many specialized hub drives and fastening methods I get kind of lost in them all until I have it right in front of me to look over 100%. There's a whopping number of solid drive hub designs and ideas out there. Just one silly machine like a 3 knife trimmer may have up to 50 of those quick release hubs on it, ridiculous. You had to move most of them when going to a book size change and there were just as many individually customizable timing points too, so many chains and sprockets under the covers you wouldn't believe it. You had to retime the various pickup or dropoff points at every handling of a book to various press speeds to get reliable performance for all day zero messup running. Ten years later and I still have bad dreams about them, LOL.


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## paulr44 (Oct 14, 2008)

I digress. Not all have a split, but all have through-bolts.


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## finaprint (Jan 29, 2006)

X2 to that.


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## nbpt100 (Jun 1, 2015)

I am not sure about this one but those insert bushings are usually tappered and often have jacking holes. By that I mean tapped holes that you can put two bolts in and tighten to press the bushing off of the pulley. From the picture it does not appear to have any. Did you try to push the pulley inwards. As someone said earlier, you only have to move the pulley inward a few thousandth of and inch to release the press fit of the tapered bushing. It looks like you were able to rotate it relative to the bushing. because I dont see the bolt holes aligned. Did you try tapping it gently along the outside to help release it?


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