RTV 900 -- Old vs New

[SRT]

I bought a new Kubota RTV 900 about five years ago -- it must have been an '06 or '07. It was destroyed in a fire last year, and I replaced it with a new (2010) RTV 900. The new one seems to have much less power than the old one -- my dealer has looked it over, and seems to be convinced that it's operating normally.

This isn't just perception. I pulled the same boats up hills with the old one, that my new one can't handle.

So the question is: What's going on here? Have they changed the gearing? Have the new engines been detuned? What?

And -- is there anything that can be done about it without making major modifications?

 

[SpudHauler]

You may want your dealer to check the 'high pressure relief valve pressure' for the forward and reverse side. It is supposed to be 3280 to 3840 psi. Low pressure will cause it to sit there and just moan and do nothing when pulling heavy or trying to climb steep slopes. Make sure it is set to 3840.
My RTV1100 was low from the factory and because it's hard to get the plugs out to check, no one does it. Plowing snow or stuck in high traction conditions, I would get the situation where it just sits and the relief valve pops and lets the pressure by-pass until you reduce the load. This way nothing gets hurt in the HST system. Adjusting it up helped. Too much and you blow up the HST!
The number of hours on this engine seems to make a big difference too. And I guess the HST is being broke in at the same time. Anyways, mine with +120hrs definitely works better than at 50 hrs.

 

[SRT]

You may want your dealer to check the 'high pressure relief valve pressure' for the forward and reverse side. It is supposed to be 3280 to 3840 psi. Low pressure will cause it to sit there and just moan and do nothing when pulling heavy or trying to climb steep slopes. Make sure it is set to 3840.
My RTV1100 was low from the factory and because it's hard to get the plugs out to check, no one does it. Plowing snow or stuck in high traction conditions, I would get the situation where it just sits and the relief valve pops and lets the pressure by-pass until you reduce the load. This way nothing gets hurt in the HST system. Adjusting it up helped. Too much and you blow up the HST!
The number of hours on this engine seems to make a big difference too. And I guess the HST is being broke in at the same time. Anyways, mine with +120hrs definitely works better than at 50 hrs.

Thanks. I'll have the dealer check the pressure. I'm right at 50 hours now, so maybe a little more "break-in" will help too.