Settling boom

[therick]

I have a 1990 743 Bobcat and it settles while boom is up. I haven't noticed any oil on ground. Any ideas and/or fixes to slow it down or stop it? TIA

 

[Fabricator]

Settles? Over how much time? While operating or once the machine is off?

 

[therick]

Settles? Over how much time? While operating or once the machine is off?

The boom drops slowly but steadily while machine is off. Foot per half hour approximately

 

[foton]

chances are a hydro cylinder is bypassing internally IMO if it does not drop so fast that you notice it while the machine is operating let it go till it gets worse and you are not there yet ,BTW I see new cylinders do this.

 

[cedolvin]

Sounds like the lift cylinders need to be rebuilt. Just went through this with our tilt cylinders.

 

[Fabricator]

That would be expected - it's why there is a prop on newer models. You shouldn't leave the arms up when shut off - and never climb out from under lifted arms. You see people getting crushed and killed that way.

That it drops that much could be a symptom of wear, but I agree with foton.

 

[therick]

chances are a hydro cylinder is bypassing internally IMO if it does not drop so fast that you notice it while the machine is operating let it go till it gets worse and you are not there yet ,BTW I see new cylinders do this.

What's IMO?

 

[JimH]

It's pretty easy to check to see if the lift cylinders internal seals are letting fluid by. Raise the boom all the way up. Support it up safely! Remove the top hydraulic connection on one side at a time. Start up the Bobcat and use the controls to attempt to make the boom go up. If fluid comes out the open hydraulic connection at the cylinder, it is by-passing the cylinder seals.

 

[foton]

IMO= in my opinion