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replacing seals on variable speed pulley (740 tt)

2.8K views 6 replies 3 participants last post by  LivingAndLearning  
#1 ·
Does anyone have any experience and guidance regarding how to take the driven variable speed hydraulically actuated feeder house drive pulley apart to replace seals? My pulley started leaking oil and my guess is the piston is leaking. Looking at the parts explosion I am not sure which pieces I can leave alone and which have to come off to get to the piston assembly.

any suggestions are greatly appreciated.

 
#5 ·
My tech had mine apart twice this season. If i remember right, after the brace and hoses, it was a special clamp to hold both outer pulley halves together to keep them from spinning. Then a special spanner socket to remove the nut. The oring isnt that big and can easily be damaged sliding it over the splines on the shaft.
 
#7 ·
what you are describing is basically what I found inside the driven. I found about 6 different "seals". A combination of o-rings and lip seals.

For anyone using this thread in the future, It does need to be removed from the machine as a unit in order to dissemble. I had to borrow the dealers "special" tool in order to safely compress the spring and release the half moon plates that lock the outer shive and spring in place. The special tool is a heavy duty threaded rod with a 1 inch thick steel plate at each end to first compress the spring and then slowly release it. Our dealer told us not to try and use a press as most do not have enough travel to fully release the springs pressure. Be forewarned that CLAAS shive disassembly instructions and the tool assembly instructions provided to the dealer mechanics, did not match our combines implementation.

thanks everyone