Bobcat 751 lift arms shudder when being touchy

[demetrios007]

I have a 751 that had leaking spool seal in 2016. Before snow season I replaced both spool seals and also took care of a drip on the emergency lift arm release by changing that whole block out. Plowed with it last 2 winters with no issues just fluid swaps etc like usual. I rarely use the machine otherwise but I am doing some work around my house with it lately. I noticed that when I have pallet forks on and I'm being precise with lifting or lowering the arms very slowly the arm cylinders stutter slightly like the fluid going to the cylinders is pulsing if that makes sense. It's not smooth like it was years before I almost think the fluid isn't going in evenly to cylinders like a pulsing. Its minor but I wanna address it sooner than later. Throttle position doesn't seem to matter and full rocking of pedal either way works fine and smooth machine seems to have full power to lift loads. May have been like this since spool seals swap I never did touchy work with the pusher or bucket on in the snow to notice it and my guy who also ran it in snow never noticed. Fluid has been swapped twice and new hydro filter too since seals. Any ideas on where to look? Thanks in advance for any help

 

[DIYDAVE]

I'd look for a hose that looks deteriorated. Sometimes hard to isolate, so start with lift/lower hoses. Sometimes a hose can have a piece of rubber that forms a flap, inside the hose. One way, it operates smooth, other way, it acts as a check valve...

 

[Vetech63]

I'd look for a hose that looks deteriorated. Sometimes hard to isolate, so start with lift/lower hoses. Sometimes a hose can have a piece of rubber that forms a flap, inside the hose. One way, it operates smooth, other way, it acts as a check valve...

Then...….when it finally separates, it flows through your hydraulic system and your machine becomes Cybil.

 

[demetrios007]

Thanks for the replies. I'll look it over real well this weekend. I was thinking more along the lines of something being off in the hydraulic block. I know theres a ton of little passages and release valving I was thinking something was sticking inside the block. Searching Google and the site turned up nada