I have a Z421 zero turn. The fan on top of the HST pulley broke. I’ve purchased a new one but can’t seem to get the old pulley off. Is it just the nut or do I need a pulley puller? What can I hold the pulley with to keep it from spinning?
Z421 HST Pulley Removal
- Thread starter Silliw68
- Start date
If it's like my hydrogear transmissions, the pulley and fan is keyed and must be pulled off with a puller.
use impact wrench, zip the nut off. Then yank the pulley off by hand. It just sits on it's hub. The hub can occasionally be a bear to get off but not all that often.
there is a bulletin out for the z4xx series that addresses frequent belt throwing, and if you have experienced it, it would be wise to have the dealer address it if it's still got any warranty on it. They are installing wider/deeper hst pulleys, tensioner is a little different, and some other stuff. It is an impressive kit.
for those that want to change their own pulley the LH one is easy, get right to it from aside the fuel tank. The RH one, you will be inventing new words. Remove the HST. There's another way, which I won't get into, it's a pain in the back side and it's just easier to remove the HST.
there is a bulletin out for the z4xx series that addresses frequent belt throwing, and if you have experienced it, it would be wise to have the dealer address it if it's still got any warranty on it. They are installing wider/deeper hst pulleys, tensioner is a little different, and some other stuff. It is an impressive kit.
for those that want to change their own pulley the LH one is easy, get right to it from aside the fuel tank. The RH one, you will be inventing new words. Remove the HST. There's another way, which I won't get into, it's a pain in the back side and it's just easier to remove the HST.
HMMM... Just upgraded my wife's hydrogear zero turn with new pulleys, new cooling fans and a new belt. Never looked at the pulleys, just replaced them. She was tossing belts and the belt ate one of the cooling fans. The whole kit was 90 bucks but I had to drop the pumps to install them. No room to get to the nut on the shaft.
The right side can be accessed by using a flex head ratchet and then inventing new words while using your other (free) hand to kinda halfway hold the pulley while loosening the nut. Since the pulley is splined to the hub, after you loosen the nut a few turns the pulley is then able to free itself from the splines, and there is loctite on the threads so you find yourself turning the shaft a lot, but never loosening the nut. So you have to kinda hold the pulley down onto the hub while loosening the tight nut and there's exactly enough room for a chinaman to get his little bitty slanted hand in there to hold it, and I am FAR from that type of person. My hands are arthritic and swollen, and I'm a little less than 6'8" so getting my big hands into small areas isn't my thing, hence the reason I absolutely hate construction equipment repairs and BX repairs.
All hydrogear transmissions are not the same. Seems like each manufacturer of the mower that your hydrogear units are bolted to has a different way of doing things. Hustler, for example, mounts their HST's in the frame backwards (normal LH side goes on the right and vice versa), and the pulleys are installed upside down. But I would just as soon own a Murray before a Hustler anyway. I don't hear of the HST's falling out of Murray mowers very often like they do on the Hustlers. Some of the bad boy Hydrogear units have a splined pulley instead of a splined hub (3 piece design, hub, pulley, fan). Then a couple others use a keyed shaft with a keyed pulley. Those tend to get stuck but it's rare to have to deal with them anyway. That's the one thing I'll say about Bad Boy, their belt system is pretty bulletproof, don't see many worn or broken belts on them. The rest of the mower? Not so much...they still have a few little issues to address before I consider them "great". But by the same token, they all have little quirks.
If you just can't wait for the dealer to do the tensioner and debris guard per the bulletin, you can buy the updated tension arm and possibly the pulleys if I can find the part numbers.
All hydrogear transmissions are not the same. Seems like each manufacturer of the mower that your hydrogear units are bolted to has a different way of doing things. Hustler, for example, mounts their HST's in the frame backwards (normal LH side goes on the right and vice versa), and the pulleys are installed upside down. But I would just as soon own a Murray before a Hustler anyway. I don't hear of the HST's falling out of Murray mowers very often like they do on the Hustlers. Some of the bad boy Hydrogear units have a splined pulley instead of a splined hub (3 piece design, hub, pulley, fan). Then a couple others use a keyed shaft with a keyed pulley. Those tend to get stuck but it's rare to have to deal with them anyway. That's the one thing I'll say about Bad Boy, their belt system is pretty bulletproof, don't see many worn or broken belts on them. The rest of the mower? Not so much...they still have a few little issues to address before I consider them "great". But by the same token, they all have little quirks.
If you just can't wait for the dealer to do the tensioner and debris guard per the bulletin, you can buy the updated tension arm and possibly the pulleys if I can find the part numbers.
Lugbolt, both of ours are Cub Cadet. I have am M60 tank, my wife has the zero turn with the steering wheel. Have the original belt and pulleys and fans on the M60 and it's 2700 hours old. Did have to replace the idler on the pump drive and one on the deck, that it. My wife's was the one I had to replace the pulleys and fans and I had to drop both hydrogears. Just not enough room between the frame floor and the top of the transmissions. Not an issue with the Tank, plenty of toom there.
Her's are sealed, mine arent. Mine each have a spin on filter and I change the oil every other year. Bought the Hydrogear fill kit, a real lifesaver and reuseable. My Kubota dealer also sells Cub Cadet.
Her's are sealed, mine arent. Mine each have a spin on filter and I change the oil every other year. Bought the Hydrogear fill kit, a real lifesaver and reuseable. My Kubota dealer also sells Cub Cadet.