Workmaster 35, power is low

miketx55 · Jun 11, 2020

Hi folks,
I volunteer for a non-profit prairie restoration property, where we have a NH Workmaster 35 4x4 tractor. It's been a great tractor, but lately it has a loss of power (bucket lifting, drive speed fwd/rev, and all speeds, etc). The engine runs fine....no issues there. Since everything is hydraulic driven, I'm wondering if I have a hydraulic problem. We did have a hyd line crack last year (the ones that run underneath and crossover.....very poor bracket design which cracked the hose). We replaced the line and all filters, added fluid (Tractor Supply Traveller Universal (had good luck with it before)), and everything has been fine until the last month. Ideas? Our first idea is to replace all the fluid and filters...again.

Also...anyone know where I can get a service manual cheap or free? Myself and one other guy maintain all the tractors, pumps, mowers, etc for this non-profit for free (everyone that works here does it for free, including the board members) and we don't have much money in the budget (all donation based, and not much at that). I've looked on Ebay/etc.

Thanks, Mike

DieselMonk · Jun 11, 2020

What oil exactly did you put back in? There are some Hydraulic only and some combination transmission and hydraulic. You need the later, other than that you will have damaged the HST transmission. Having power loss all around (transmission and hydraulic), I say there is a problem with the HST transmission. There is only a few things that you can do without opening the HST. You can check oil pressures on the HST, change the HST and Hydraulic filter and change the HST fluid. Other than that it's down to get the HST transmission rebuilt. Been there done that.

miketx55 · Jun 11, 2020

This is what we put in.....Traveller Tran/Hyd Universal fluid. It supposedly meets the specs.
Traveller Premium Universal Tractor Trans/Hydraulic Fluid, 5 gal.
SKU: 80639199

Description:
Traveller Premium Universal Tractor Trans/Hydrauilic Fluid is a specially formulated, premium multigrade (SAE 10W-30) fluid blended with the highest quality lubricating oils and the most technologically advanced additive system.

Provides superior protection and performance for modern farm equipment
Employs a common sump to lubricate hydrostatic transmissions, differentials, wet brakes, hydraulics and final drives gears

DieselMonk · Jun 11, 2020

That oil should be fine then. Pull the HST dipstick and smell the oil. You can try an oil and both filter change and cut the old filters open. After that the only thing you can do is a pressure test. There are a few pressure relief valves that can be exchanged, but after that the HST has to come apart.

miketx55 · Jun 12, 2020

DieselMonk said:
That oil should be fine then. Pull the HST dipstick and smell the oil. You can try an oil and both filter change and cut the old filters open. After that the only thing you can do is a pressure test. There are a few pressure relief valves that can be exchanged, but after that the HST has to come apart.

Thanks....guess we'll give the fluid/filter replacement a shot.