773g lift and tilt shimmy

[kech]

Hey guys new to the site. My 2001 bobcat 773g hydraulics pulse or shimmy on the way down. The heavier the load the more it does it, to the point it will bounce the whole machine like crazy. Anyone ever had this problem before?

 

[Bobcatdan]

Only on the way down or lifting up too? How does tilt work? One way or both directions?

 

[Tazza]

Only on the way down or lifting up too? How does tilt work? One way or both directions?

How is the oil level?
Odd that it does it on the way down, that is usually smooth, up can be jittery when low on oil.

 

[kech]

How is the oil level?
Odd that it does it on the way down, that is usually smooth, up can be jittery when low on oil.

The oil level is full and it does do it a little lifting and tilting up but doesn't seem to be as bad. I've changed all the filters including the inline ones with no change.

 

[Bobcatdan]

The oil level is full and it does do it a little lifting and tilting up but doesn't seem to be as bad. I've changed all the filters including the inline ones with no change.

Is the hydraulic oil cavitating while using ?

 

[kech]

Is the hydraulic oil cavitating while using ?

I don't think so. One guy told me to raise and lower and tilt up and down for about 5 min then get out and look in the fluid level window and see if there is air bubbles, which I did but didn't see any bubbles, so don't think it's sucking air.

 

[Tazza]

I don't think so. One guy told me to raise and lower and tilt up and down for about 5 min then get out and look in the fluid level window and see if there is air bubbles, which I did but didn't see any bubbles, so don't think it's sucking air.

That is very odd, cavetation is the main cause of jittery hydraulics.
Not sure what else it could be, tight pivot points? ram issue?
The thing is, for it to do it for lift and tilt would be pretty well un-heard of though. Having both lock up or rams fail at the same time.
Come on Dan, get that grey matter working

 

[Bobcatdan]

That is very odd, cavetation is the main cause of jittery hydraulics.
Not sure what else it could be, tight pivot points? ram issue?
The thing is, for it to do it for lift and tilt would be pretty well un-heard of though. Having both lock up or rams fail at the same time.
Come on Dan, get that grey matter working

Even thou its not cavitating, I'd still start with a direct pump test to see if the gear pump is failing. Otherwise I'd think something in the control, possibly cracked housing.