ZD221 Zero Turn

[Donnie M]

My Diesel zero turn mower runs great only
90 hrs engine hums along smoothly then deck slows down and almost stops in grass that’s a 1/2 “ and it’s not even thick blades are 2 weeks old belt looks great anyone had a similar problem

 

[mechanic mark]

Make sure spindles have been greased at all grease fittings, your entire mower as well. I purchased my lawn tractor new in 2010 & noticed Dealer had not greased any fittings.

 

[Donnie M]

Make sure spindles have been greased at all grease fittings, your entire mower as well. I purchased my lawn tractor new in 2010 & noticed Dealer had not greased any fittings.

I’ve greased all spindles and grease fittings, 2017 mower I bought it and it had 63 hrs on it, driveshaft coming out transaxle drives gearbox that drives belts

 

[Donnie M]

I’ve greased all spindles and grease fittings, 2017 mower I bought it and it had 63 hrs on it, driveshaft coming out transaxle drives gearbox that drives belts thanks

 

[bertsmobile1]

If the mower has bevel boxes on the blade spindles like say Walkers do then the PTO clutch is slipping , assuming the engine speed does not reduce
If the mower has belts driving the bade spindles then the belt is slipping or one of the pulleys is stripped out .
Unfortunately Kubots IPL's are near impossible to access down here without the full model & serial numbers
We have a couple of F2400's we are slowly coming to grips with and finding information on them has been an uphill battle .
They have a shaft drive PTO to a bevel box then belts to the blades
In this case the pulley on the bevel box had sheared the drive key so when not cutting the blades spin up fine but when attempting to mow 2' tall tussock grass the best it could do was a loose plat

 

[Donnie M]

If the mower has bevel boxes on the blade spindles like say Walkers do then the PTO clutch is slipping , assuming the engine speed does not reduce
If the mower has belts driving the bade spindles then the belt is slipping or one of the pulleys is stripped out .
Unfortunately Kubots IPL's are near impossible to access down here without the full model & serial numbers
We have a couple of F2400's we are slowly coming to grips with and finding information on them has been an uphill battle .
They have a shaft drive PTO to a bevel box then belts to the blades
In this case the pulley on the bevel box had sheared the drive key so when not cutting the blades spin up fine but when attempting to mow 2' tall tussock grass the best it could do was a loose plat

It usually cuts for an 1 -1 1/2 hrs does fine in tall grass then all of a sudden deck slows down it also has done it it short grass

 

[bertsmobile1]

Check the PTO speed
You can use one of the visual tachos
Check the speed when cold on the floor and when hot in the yard
If it is slower then the PTO clutch has seen better days if it is a fixed drive of the crank ( goes through the gearbox ) or the either the PTO clutch &/or the hydro which includes a bunch of backload & overload valves if it is anything like ours.
Kubota do a 1/2 hearted manual for most of their stuff which is no great help unless you are fairly technical savvy, as it is written for factory trained mechanics, not DIY owners.
However it will have the actual drive paths so at least you have an idea of what could be giving you grief .
They are not cheap