B2601 hydrostatic weak going uphill

[N.Stevens1404]

I have a B2601 HST with about 350 hours on it, and I've noticed a significant power loss in the hydrostatic drive lately, especially going uphill. On flat ground in high range, it drives fine, but as soon as I hit a modest incline in low range with a full dirt bucket on the front end loader, the transmission struggles and slows way down, even if the engine RPMs are high.

The loader itself seems fine and lifts the bucket without issue, so I don't think it's the main hydraulic pump. I changed the HST fluid and filters, using factory Kubota UDT, at the 200-hour mark and topped off the fluid last week, and it's right on the mark. I've heard this can be normal with these hydros, but it definitely didn't struggle this much when it was new.

Could this be a fuel restriction issue causing engine bog, air in the hydro system that needs purging again, or maybe a linkage adjustment on the travel pedal? Any insight or specific things to check on the B series would be greatly appreciated before I drag it to the dealer. Thanks for your insights!

 

[Alan]

Give the travel pedal return spring and linkage a look. If it's acting up, it could mess with the hydro output. Even with clean fluid, peek at the suction screen to make sure it's not clogged.

 

[load3rpro]

Make sure also to inspect the air intake and fuel filters, any blockages there can create problems that feel like hydro issues when the system is under load. It might also be a good idea to look into a weak charge pump or a worn relief valve.