Backhoe Kubota BH 90 Backhoe making banging sound

[JoeL3240]

I have a L3240 Kubota Tractor with a BH 90 Backhoe, which has 20 hours of use. When I move the boom from left to right or right to left there is a banging sound made by the boom, this sound is similar to what is produced when banging a large bell. From what I can see the cause of the problem is a hydraulic cylinder located inside the boom housing, which is attached between the Swivel Frame and the Backhoe Boom. As the boom moves left to right or right to left the hydraulic cylinder bangs against the inside of the boom housing. Has anyone experienced this problem? The Kubota dealer says this is normal.

 

[dillo99]

I don't have the same hoe, but this does not sound normal to me.

 

[ryer]

I have a B26 TLB. The backhoe is a BT820. I have the same exact sound. Sometimes it is quiet but most of the time, if you really swing the boom quick and then stop suddenly, you will get that ringing sound. The tractor has 260 hours of heavy backhoe use with no problems. When I look into the boom with a flashlight, I do not see any cylinder, just hoses...so I am not sure about the cylinder but I would think this noise is probably normal.

 

[dfkrug]

As the boom moves left to right or right to left the hydraulic cylinder bangs against the inside of the boom housing.

Are you sure that is what is causing the noise? These hoe attachments have
a certain amount of clearance at the pivot that attaches the boom to the
dipper. Sideways swing momentum causes the dipper to move sideways
along the pivot pin. My last Kubota hoe (BT751) had shims added in there to
reduce this movement. I added my own shims to my current hoe to cut
down on this movement and noise.

 

[art]

It is just the cylinder sliding on a pin from side to side. It is a sign of good lubrication if it is sliding and hitting the sides. Shims will tighten it up and tighten up the distance between the cylinder end and frame but I wouldn't waste a lot of time with worring about it!

 

[justcountry]

Is the locking pin hold ing up the boom when it makes the banging? if it's not, it doesnt sound right for the boom cylinder to bang if it has weight of the boom on it. I have a bh90 and don't recall hearing this sound even after 750 hrs.

 

[john_bud]

It is just the cylinder sliding on a pin from side to side. It is a sign of good lubrication if it is sliding and hitting the sides. Shims will tighten it up and tighten up the distance between the cylinder end and frame but I wouldn't waste a lot of time with worring about it!

I agree with Art, mostly. It sounds like the DEALER forgot to install the shims that keep the cylinder in the center. You will get a LOT of grit in the grease and make a fine grinding paste that will wear it out quicker.

I wouldn't waste time worrying, I would correct it.

jb