How do I tell if a hydro clutch pack is good or low on life

[johneic]

I am looking to buy a JD 455, made from 1992 to 2001, going to look at it this week, is there any way to tell the status of the hydro clutch pack?

 

[FredH]

Don't know the tractor , but in my experience with hydraulic clutch's , be they in pick up's or even Semi's , Not really . The last semi I had , you could even take off the inspection plate and visually look at the clutch components . Still did no good , cause one day , " POOF " , No clutch . Was a turd at stop signs and stop lights , but once rolling , could just slip the gears . My brothers Ford pick up was the same way . Went to shift one time and nothing .

Fred H.

 

[pmsmechanic]

There are no clutch packs in a hydrostatic transmission. There's a variable displacement hydraulic pump and a motor. The variable displacement provides different speeds and the hydraulic flow through the pump is reversed for direction changes.

 

[johneic]

Thanks, I guess i was misinformed a long time ago, I was told there is an expensive clutch pack in a hydrostatic trans that wears out over time.

 

[ericm979]

There's always a clutch somewhere in an HST tractor- either between the engine and the HST and PTO, or there's an independent PTO clutch outside the HST unit itself. The latter can be wet multiplate clutches. They're in the transmission housing (along with lots of other stuff) but they're not part of the transmission that's turning the wheels.

 

[DieselMonk]

That clutch pack you are referring to may be a Hydro Power Reverser Clutch or Hydro Power Shuttle. These are found on geared tractors only. With that you can change direction (forward / reverse) without clutching the transmission.
I have one HST that has no clutch at all and another one that has a clutch between the engine and HST/PTO. This clutch isn't different from a clutch on geared tractors.

All you can do on the HST is check and smell the oil, see if there is a external oil cooler and she isn't jerking, has smooth power while the oil is hot (after a 30min ride around the bahoogies) and doesn't whine hard. If there is a problem with the HST, as soon as the oil gets hot you are going to loose power. By that I mean you are going to have lower speed, than with cold oil. Listen to the HST for any weird noises like oil bypassing. So let someone else drive the tractor, while you walking beside it and listen to each side.

 

[Fallon]

There's always a clutch somewhere in an HST tractor- either between the engine and the HST and PTO, or there's an independent PTO clutch outside the HST unit itself. The latter can be wet multiplate clutches. They're in the transmission housing (along with lots of other stuff) but they're not part of the transmission that's turning the wheels.

Not always. My L3200 had a clutch that was only usefully for starting the PTO (it killed the PTO & HST tranny when engaged... Or is that disengaged). My L4060 doesn't have a clutch pedal at all given the electro-hydraulic PTO engagement.