Zd21 belt change

[10ecman]

I changed the belt on my zd21. The belt came with the mower but instead of 120” it was 115 and I heard a loud screech and now the blades will not turn. The rpm’s go down when you push the lever forwards but no turning of the blades. What did I do to this mower??

 

[Captain13]

Sounds like you the belt routing is wrong. Can you take the tension off the belt and turn the spindles? If so, the belt is probably on wrong.

 

[Daren Todd]

5" difference in length on a belt is huge. If it's routed correctly, I would say the belt is way too tight and causing everything to bind up.

If the old belt measured 120" then you need a new belt that's 120".

The grooved "V" portion of the belt wearing over time and is what causes the slippage.

 

[D2Cat]

If the belt is 5" shorter than what you took off it will not fit unless you have it improperly installed. You can't stretch a belt 5" without it separating. !!!!!

 

[Daren Todd]

If the belt is 5" shorter than what you took off it will not fit unless you have it improperly installed. You can't stretch a belt 5" without it separating. !!!!!

The belt tensioner on mine could probably accept a smaller diameter belt. But dang, with the spring tensioner as tight as it is, you would have to have some serious booty behind you to compress it that much

 

[Captain13]

Wow. Missed the part about the belt size..

 

[10ecman]

The belt tensioner on mine could probably accept a smaller diameter belt. But dang, with the spring tensioner as tight as it is, you would have to have some serious booty behind you to compress it that much

Yeah I went and got a belt from Kubota dealer but it still is doing nothing. I heard a loud screech and I shut it down but I got nothing now. Lever for the blades activated but no blades turning. It’s as if the hst has an internal shaft that i somehow broke.

 

[10ecman]

The belt tensioner on mine could probably accept a smaller diameter belt. But dang, with the spring tensioner as tight as it is, you would have to have some serious booty behind you to compress it that much

I had to use a big pry bar and 4” diameter 3’ cheater bar

 

[10ecman]

If the belt is 5" shorter than what you took off it will not fit unless you have it improperly installed. You can't stretch a belt 5" without it separating. !!!!!

Threw the old belt away before I put the “new” belt on so no measurements.

 

[Russell King]

There is no way that you should have to use that type of force to put the correct belt on in the correctly routed position.

I would think that you have now messed up the new belt or the tensioning system.

I think you now need to get it fixed by a dealer or someone that has some experience with the belt routing on the deck unless you are 100% sure you know what you are doing.

if you threw the old belt away then how do you know it was 120 long? Is the belt routing clearly indicated on the deck or in a manual?

Where did the new belt come from? A dealer or was it with a mower that you purchased from another owner?

 

[10ecman]

There is no way that you should have to use that type of force to put the correct belt on in the correctly routed position.

I would think that you have now messed up the new belt or the tensioning system.

I think you now need to get it fixed by a dealer or someone that has some experience with the belt routing on the deck unless you are 100% sure you know what you are doing.

if you threw the old belt away then how do you know it was 120 long? Is the belt routing clearly indicated on the deck or in a manual?

Where did the new belt come from? A dealer or was it with a mower that you purchased from another owner?

I threw the old belt away. The one that I put on was a new spare which came with the mower. The zd21 belt is 119.5” the “spare”was about 115 as measured. It now has a dealer belt on it which is 120”. Yes it was with the mower. I’ll figure it out eventually thanks for the help guys.

 

[Russell King]

Okay that clears up a few details about it.

So did you ever install the 115 inch belt?

If you have the 120 inch belt on and it took a cheater bar to get it on the the routing must be incorrect.

The squeal is probably the belt slipping on a pulley or possibly a bearing in the mower.

The difference between the required 119.5 and 120 is probably insignificant if it is being pulled tight by the spring. Does the spring still have quite a bit of tension or is there some adjustment to add more or less tension?

 

[10ecman]

Okay that clears up a few details about it.

So did you ever install the 115 inch belt?

If you have the 120 inch belt on and it took a cheater bar to get it on the the routing must be incorrect.

The squeal is probably the belt slipping on a pulley or possibly a bearing in the mower.

The difference between the required 119.5 and 120 is probably insignificant if it is being pulled tight by the spring. Does the spring still have quite a bit of tension or is there some adjustment to add more or less tension?

Yes the squeal was with the 115” belt and it needed the cheater bar to get it on. I figured since the belt was with it it would be a belt that fit. My assumption may have cost me.

 

[10ecman]

Okay that clears up a few details about it.

So did you ever install the 115 inch belt?

If you have the 120 inch belt on and it took a cheater bar to get it on the the routing must be incorrect.

The squeal is probably the belt slipping on a pulley or possibly a bearing in the mower.

The difference between the required 119.5 and 120 is probably insignificant if it is being pulled tight by the spring. Does the spring still have quite a bit of tension or is there some adjustment to add more or less tension?

The belt is tight and the spring does have sufficient tension. I am afraid I broke something in the deck gearbox. The pulleys do not turn easily with the belt on at all.

 

[Russell King]

I would get the belt off the tension pulley and see if every pulley turns easily.

I might even take the deck off the tractor now so you can get to the pulleys easily if you’re pretty sure it is one of the pulleys squealing

Good luck

 

[10ecman]

I would get the belt off the tension pulley and see if every pulley turns easily.

I might even take the deck off the tractor now so you can get to the pulleys easily if you’re pretty sure it is one of the pulleys squealing

Good luck

I think it’s broken something in the hst. If it’s running and you push the blade handle forward it acts as if it’s under extreme load. The last pic is of a deck I have that is rusted completely through. It appears that the belt is routed the exact same way. You are correct the blades do not turn like the deck that is shot so I’m wondering if I messed up the pto in the hst or the gearbox on the deck.

 

[Russell King]

I think you should get the deck off and see if the tractor is still fine. I don’t think you would have damaged the tractor by putting on a deck belt.

The deck might just be so messed up that the tractor can’t spin the deck (like trying to start the deck from stand still in really tall thick grass would stall the tractor).

Since you have the spare deck you can just move good parts from that deck to the good sheet metal deck and get back up and running?

 

[10ecman]

I think you should get the deck off and see if the tractor is still fine. I don’t think you would have damaged the tractor by putting on a deck belt.

The deck might just be so messed up that the tractor can’t spin the deck (like trying to start the deck from stand still in really tall thick grass would stall the tractor).

Since you have the spare deck you can just move good parts from that deck to the good sheet metal deck and get back up and running?

That’s my plan but I wanted to liquidate the spares. I just sold the motor out of the trashed mower. I HATE making a mistake with parts I didn’t need to fix and now you need to replace. Thanks for the help and I’ll remove it. I KNOW it doesn’t soon like the Swiss cheese deck

 

[10ecman]

That’s my plan but I wanted to liquidate the spares. I just sold the motor out of the trashed mower. I HATE making a mistake with parts I didn’t need to fix and now you need to replace. Thanks for the help and I’ll remove it. I KNOW it doesn’t soon like the Swiss cheese deck

Spin like the Swiss cheese deck

 

[10ecman]

I think you should get the deck off and see if the tractor is still fine. I don’t think you would have damaged the tractor by putting on a deck belt.

The deck might just be so messed up that the tractor can’t spin the deck (like trying to start the deck from stand still in really tall thick grass would stall the tractor).

Since you have the spare deck you can just move good parts from that deck to the good sheet metal deck and get back up and running?

I found the problem the gearbox on the deck was the culprit. It was I think the small belt snapped something inside. I haven’t looked at it but the gearbox literally fell apart when I started to take off the deck.