How to Remove HYDRO GEAR 72972 TRANSMISSION FAN PULLEY

[scottchopchop]

How to Remove HYDRO GEAR 72972 TRANSMISSION FAN PULLEY

On a Gravely ZT HD 60

Replaced the other side a couple of years ago and cannot for the life of me remember how I got the nut off to allow removal of the assembly. Do remember thinking I got lucky.

So far, I have tried this clutch pulley removal holder device thing. Tried putting some screws all the way threw the three little holes in the fan and into the pulley below.

Have only succeeded in ripping the fan off.

I have cussed quite a lot. I feel like I have cussed sufficiently that the nut should have come off by now. I am stumped.

How do I get this off?

New part arriving soon.

 

[MParr]

Impact wrench or a socket and ratchet top side and an open end wrench underneath.

 

[Auto Doc's]

An 18V 1/2-inch drive Ryobi impact with correct socket will know the nut off quickly. Then it is a matter of getting the pulley off if you have to.

 

[Tiger Small Engine]

An 18V 1/2-inch drive Ryobi impact with correct socket will know the nut off quickly. Then it is a matter of getting the pulley off if you have to.

I recently removed a hydro fan on a Scag because it was damaged and needed to replace it. It was on there gorilla tight with Loctite. I had to put three pairs of vise grips on fan and use a ratchet and cheater pipe to get it off. Then I had to file the pulley smooth from slight burrs from vise grips.

 

[StarTech]

I recently removed a hydro fan on a Scag because it was damaged and needed to replace it. It was on there gorilla tight with Loctite. I had to put three pairs of vise grips on fan and use a ratchet and cheater pipe to get it off. Then I had to file the pulley smooth from slight burrs from vise grips.

Why? The shaft adapter has a double flat ground on it.

The problem is it is a odd size tool wise. It is 29/32" open end wrench size and a 15/16" (24mm) is a loose fit and 7/8" won't fit. The 15/16" will work most times but I prefer take an el cheapo wrench and grind or file the opening to 29/32". Otherwords you need a custom open end wrench for a good fit. Or a large adjustable wrench would be a second option. Most mechanics do have adjustable metric/SAE wrenches.

But for piece of mind don't ask the Lowe's tool guy for a Metric adjustable wrench. The one I did ran around like a chicken with its head cut off; until, he asked his supervisor. Then I got some really hard looks. But I bet he will remember that one. The handle length can spec'd in mm.

Why Hydro Gear used an odd ball size is just to be a pain I reckon.

 

[scottchopchop]

Why? The shaft adapter has a double flat ground on it.

The problem is it is a odd size tool wise. It is 29/32" open end wrench size and a 15/16" (24mm) is a loose fit and 7/8" won't fit. The 15/16" will work most times but I prefer take an el cheapo wrench and grind or file the opening to 29/32". Otherwords you need a custom open end wrench for a good fit. Or a large adjustable wrench would be a second option. Most mechanics do have adjustable metric/SAE wrenches.

But for piece of mind don't ask the Lowe's tool guy for a Metric adjustable wrench. The one I did ran around like a chicken with its head cut off; until, he asked his supervisor. Then I got some really hard looks. But I bet he will remember that one. The handle length can spec'd in mm.

Why Hydro Gear used an odd ball size is just to be a pain I reckon.

Is the shaft adapter on the underside of the pulley? Between the pulley and the Hydro Gear unit? Do you have to remove the tire to get the wrench back up in there? Thanks.

 

[StarTech]

Yes to the first two questions and I can't answer the third question as It all depend the access needed and your ability. But the image posted it looks you have enough clearance without having to take wheel off. Might be a tight fit for your hands however. From that image I would be worry about the transaxle input bearing as things have been really hot.

 

[StarTech]

Update I just found that some ZT2800,3100, and 3200 built before ZJulian date 1213XXXXX (2012)have a different pulley setup. Matter of fact I found an Ariens here [basically the same as a Gravely] has two different pulley on the same mower. One side has a all in one pulley hub assembly and it does not have the flats. In this case it is LH one as the RH does have the separate hub with the flats.

Conclusion is that you might need a pipe wrench to get a hold on the older pulley/hub.

 

[scottchopchop]

Got it off. Pics attached.

This one is drivers side (LH when sitting and mowing)

Didn't have to remove the wheel. Working totally blind and only by feel was able to get a crescent wrench threaded in that space and resting on top of the PTO belt.

Fiddled with the sizing on the wrench a bit, moved the position of the flat spots below the pulley by turning the flywheel. Magic happened and the wrench slipped into place. Tightened the crescent a touch.

Used a regular ratchet with a long extension...not much pressure required.

Once the nut was removed, released the spring tightener on the PTO belt and the whole assembly came out fairly effortlessly.