Bobcat 322 Dipper Arm Dropping

[Mick-the-fitter]

agreed with the ram fully extended Bri, but still disagree with it fully closed, holding the dipper up ... it will pass sufficient fluid to prove the seal fault, before any induced vacuum stops the motion

Would you not close the dipper ram and rest the dipper on a prop, remove the hoses from the dipper ram, cap both ends of the ram, join the hoses, start the machine and using the boom lift the dipper off the prop! If the dipper drops then it’s a seal issue or a cylinder score!

 

[Bri963]

That would work as well.

 

[V8Druid]

Would you not close the dipper ram and rest the dipper on a prop, remove the hoses from the dipper ram, cap both ends of the ram, join the hoses, start the machine and using the boom lift the dipper off the prop! If the dipper drops then it’s a seal issue or a cylinder score!

that's what I suggested, apart from joining the hoses, rather than capping them and I advocated sitting the dipper on the floor to do it, rather than a prop.

 

[Mick-the-fitter]

that's what I suggested, apart from joining the hoses, rather than capping them and I advocated sitting the dipper on the floor to do it, rather than a prop.

Yes the same thing Sir! That is where I would start any way

 

[mpb]

Thank you for all the advise, can some one advise me what size caps and plugs I need.

The hard lines are 3/8 and the female nuts are 18mm or 11/16. This is a bobcat from about 2000.

Many thanks

Martin

 

[V8Druid]

Thank you for all the advise, can some one advise me what size caps and plugs I need.

The hard lines are 3/8 and the female nuts are 18mm or 11/16. This is a bobcat from about 2000.

Many thanks

Martin

bloody metric fittings ........ I BSP

 

[Shovelhands]

Thank you for all the advise, can some one advise me what size caps and plugs I need.

The hard lines are 3/8 and the female nuts are 18mm or 11/16. This is a bobcat from about 2000.

Many thanks

Martin

Take a picture of the union and a pic of it separated, so the thread can be seen and the cone etc.

If you’ve not bought anything, then this test could probably done with a ball valve fitted in the the appropriate line, but this will be more expensive than caps and plugs.

 

[Bri963]

that's what I suggested, apart from joining the hoses, rather than capping them and I advocated sitting the dipper on the floor to do it, rather than a prop.

Just re-read your first post properly, Gra. Could have saved myself a lot of writing.

 

[V8Druid]

Just re-read your first post properly, Gra. Could have saved myself a lot of writing.

LOL ... can't see the wood for the trees sometimes Bri ... been there, done that !

 

[mpb]

Just an update. Called in to the local hydraulic hose shop and the threads are 9/16 JIC. Just waiting on the plugs and caps to come into stock.

 

[Mick-the-fitter]

Be good to keep hold of them once you get them!

 

[Mick-the-fitter]

I was going to say more so with a bobcat but I won’t!

 

[mpb]

Problem solved. Capped off the ram and the dipper arm didn’t move.

So I took the floor out and took the prv out. In the end there looked to be pieces of a broken o ring holding it open. Remove the debris put it back together and it works.

I don’t know where the rubber has come from but it’s working again.

Thank you for all your help and advise.

 

[Mick-the-fitter]

Probably an “O”ring left over on a Friday at five to five! Thrown in for good measure

 

[topkit]

Had a similar problem on my Yanmar B15-3 with the boom dropping originally had the boom ram re sealed. Then had a look at boom pilot control and found it was partially sticking on the up/down plane of the control so cleaned it and lubed it and the problem was solved.

 

[V8Druid]

Problem solved. Capped off the ram and the dipper arm didn’t move.

So I took the floor out and took the prv out. In the end there looked to be pieces of a broken o ring holding it open. Remove the debris put it back together and it works.

I don’t know where the rubber has come from but it’s working again.

Thank you for all your help and advise.

possibly a hose inner breaking up ...

 

[V8Druid]

I don’t know where the rubber has come from but it’s working again.

Thank you for all your help and advise.

possibly a hose inner breaking up ...

this is what I had out of my return filter when I had an LS issue with my 'Drema ...

cleaned the LS port restrictor out

and blew the line from that to the pump out

catching what came out ... re-assembled and been fine since