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Josiah deshong

620 hydro hard shift forward/reverse

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Josiah deshong

Hello everybody I have been plowing snow with my powermax since I got it running in November and everytime I run it when I go from forward to reverse the hydro is getting really hard to move and when it finally let’s go it takes off hard I’m worried if I’m anywhere with traction that I might tear an axel up has anyone encountered this problem before, it shifts easy when  it’s not running so it’s not linkage I don’t think and the higher rpm the engine is the harder the shift is thanks always for any help 

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Hey Josiah

Sorry to here that. I would suggest pulling the hydro and check the swash plate to trunion shafts fit. I think there will be excessive play in the fit between them.  Do you have fluid leaking out around the seals on the trunion and shift shaft? That would indicate problems with  them. I wouldn’t run it anymore until checked. If the shafts have play in them the retainer roll pins are broke. You don’t want broken pins going through the hydro. That would be very $$$.

good luck Mike


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Josiah deshong

I’m gonna take a look at it here tonight. Is changing the hydro unit a pain in butt just like everything else on the powermax I have another hydro I could try and just have this one rebuilt but if it’s really involved I don’t wanna stick one in that might not b no good or any better then the one that shifts hard thanks

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