s650 Lift arms weak

landscapers650 · Jan 11, 2020

Hello
Hoping to get input on problem with my S650 bobcat.
After running for few minutes lift arms are not able to handle load. Bucket tilt and mobility are fine. Also will go into 2 speed just fine. Oil level is fine, also just replaced hydraulic oil filter and problem continues. Any thoughts?

phil314 · Jan 12, 2020

What kind of controls do you have?
Foot, AHC, SJC??

landscapers650 · Jan 12, 2020

Foot controls

92U 3406 · Jan 12, 2020

I'd start with checking that the pressures are within spec.

If it gets weak when hot, I'd work the machine to get the oil hot, then shoot the lift cylinders with a temp gun. If one is significantly hotter than the other, I'd suspect the hot one is leaking internally.

Bls repair · Jan 13, 2020

I would check for dirt or garbage underneath the pedals limiting movement.

Joseph Marasco · Jan 13, 2020

If it is like our S650, I think ours are 2018, the pivot for the foot controls are mounted under the seat. They only have a thin plastic bushing in there. Maybe they're worn and not allowing full motion of the spool? One of our machines, not properly cleaned after last plowing season, had an issue where the pivot pin actually rusted off of the plate. We had to weld it back on and replace the bushing.

mikebramel · Jan 13, 2020

Connect gauge at test port

Compare dead head pressure between bucket tilt and boom functions.... if different... check cylinders or port relief on lower function

If same... check pump... relief valve etc

s650 Lift arms weak

landscapers650

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phil314

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landscapers650

New Member

92U 3406

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Bls repair

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Joseph Marasco

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mikebramel

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