Kubota T1880 Won't Drive

[Pat_USA]

The problem began when I had the riding mower supported with a wooden stool and a 4-way lug nut wrench due to one flat tire. After reinflating all the tires, I forgot to remove the stool and wrench. When I drove the mower a short distance, it got stuck. I tried moving it forward and backward, but it wouldn’t budge. Upon closer inspection, I found one side of the wrench embedded in the dirt in an upright position (like + sign) in front of the decking. After freeing it, the mower would start and run, the blades engaged, but it still wouldn’t drive.

Both rear wheels have the key pins intact, but when jacked up, both wheels spin freely (one wheel spins forward and the other backward). I understand they are supposed to spin slightly and lock—am I correct?

I believe the issue arose from attempting to drive the mower with the 4-way lug wrench lodged upright in the dirt in front of the deck.
What else should I check that could be preventing the mower from driving? Please Advice.

 

[Caden]

I believe that mower uses a belt driven transmission, so I'm thinking that the lug wrench may have thrown your drive belt off the pulley.

 

[Pat_USA]

I believe that mower uses a belt driven transmission, so I'm thinking that the lug wrench may have thrown your drive belt off the pulley.

The drive belt and deck belt are still intact, which is why the blades engage.

 

[Caden]

The drive belt and deck belt are still intact, which is why the blades engage.

Drive belt has nothing to do with blade engagement.

Could some severe misalignment of the deck by the lug wrench have affected your pedal linkages to the transmission?

 

[Pat_USA]

Drive belt has nothing to do with blade engagement.

Both the drive belt and deck belt are spinning, but I can't attach the short videos in this forum. The attached photo shows the front pulley of the deck belt, which the belt is positioned in the middle of the pulley; I believe it should be on the bottom section. When the mower runs, the deck vibrates more than normally.

 

[Caden]

I believe it should be on the bottom section. When the mower runs, the deck vibrates more than normally.

From photo, It looks like the belt can be anywhere on that pulley, probably dependent on what hight the deck is at (i.e. angle of belt coming in).

For your vibration: did the lug wrench end up under the deck at all, in a way that could have bent a blade?

Or, if the deck was forced up into the frame of the tractor, it could have bent any of the idler pulleys or spindle pulleys causing vibrations. This also could have affected your drive linkages maybe?

One other idea, are the belt tensioner spring where they should be to ensure the belt is not slipping?

 

[Pat_USA]

From photo, It looks like it the belt be anywhere on that pulley, probably dependent on what hight the deck is at (i.e. angle of belt coming in).

For your vibration: did the lug wrench end up under the deck at all, in a way that could have bent a blade?

Or, if the deck was forced up into the frame of the tractor, it could have bent any of the idler pulleys or spindle pulleys causing vibrations. This also could have affected your drive linkages maybe?

One other idea, are the belt tensioner spring where they should be to ensure the belt is not slipping?

I don't think the wrench went under the deck. It got stuck in the dirt (about 4" deep) in front of the deck and was pointing upward beneath the rider. Removing it was challenging, but I managed to get it out. I should have taken a picture before removing it, as I didn’t anticipate the problem that followed the incident.

I don’t know where the belt tensioner spring; if you have a picture, I can check it out.

 

[Caden]

if you have a picture, I can check it out.

Sorry I can't be of more help, as I don't have this mower or any experience of working on one, therefore I do not have a picture.

My guess for spring location is between the frame rails of the tractor maybe about halfway between front and rear wheels. I kinda doubt it's your issue but maybe worth checking.

 

[Pat_USA]

Sorry I can't be of more help, as I don't have this mower or any experience of working on one, therefore I do not have a picture.

My guess for spring location is between the frame rails of the tractor maybe about halfway between front and rear wheels. I kinda doubt it's your issue but maybe worth checking.

I don't think that is the issue too.
I have attached a picture to show how the wrench was stuck under the rider and partially buried in the dirt.

 

[Caden]

The only other point I could think to check, other than transmission internal, it the main pulley on top of the transmission. Should have spines to fit on the input shaft of the transmission. I have seen lawn mowers strip these splines occasionally when under heavy load, meaning the pulley is freewheeling on the transmission shaft.

 

[Bee-Positive]

Download the operators manual HERE

 

[Bee-Positive]

The PTO Belt will also have a tensioner mounted on the tractor right about were the #1 arrow is pointing.

 

[Pat_USA]

The only other point I could think to check, other than transmission internal, it the main pulley on top of the transmission. Should have spines to fit on the input shaft of the transmission. I have seen lawn mowers strip these splines occasionally when under heavy load, meaning the pulley is freewheeling on the transmission shaft.

I watched a couple of YouTube videos where they replaced the transmission fan. I'm new to small engine repair, but I will check it out tomorrow.

 

[Pat_USA]

The PTO Belt will also have a tensioner mounted on the tractor right about were the #1 arrow is pointing.

I thought this mower only had two belts, but it appears there is a PTO belt located above those two belts, correct?
I will check it out tomorrow & thank you so much for the diagram. I will need to replace the drive belt sometime soon.

 

[Bee-Positive]

Also, are you sure you didn't bend the belt support where it goes into the deck? Arrow #4 in diagram. Might to be out of alignment causing vibration.

 

[Caden]

I thought this mower only had two belts,

According to that diagram it has 3. I have been referring to the topmost belt, in between the frame rails that runs to the transmission which has no impact with the deck whatsoever.

 

[Bee-Positive]

There are not 3 belts
1 deck belt
1 PTO belt

In your picture - post #5 above - the PTO belt should ride on the top and the deck belt should ride on the bottom of that pulley.

 

[Caden]

There are not 3 belts

Based on the diagram, it looks like there is one belt that connects the 2 spindles.
One belt to connect the deck to the pto.
Logically, there must be one more belt to connect the engine to the transmission. No?

 

[Bee-Positive]

No.

There is a shared pulley that's the connection to drive the deck.
See the picture in Post #5 with one belt in the middle.
Should have 2 belts - PTO on the top, deck on the bottom.
That's the driver.

 

[Bee-Positive]

Shared pulley (pictured in post #5) highlighted in yellow.