Rebuilding bucket cylinder

[JR79]

Good morning,

I am rebuilding my bucket cylinders on my L275. I believe the loader is an L1730 based on my research but cant be sure because the tag is partly un legible.
Have not had much luck finding info regarding a torque spec on the bottom of the piston. Two questions, is this a critical torque or does it just need to be tight? And how to verify I have the correct loader model number so I can try to source a manual.

Thank you.

 

[Dave_eng]

Good morning,

I am rebuilding my bucket cylinders on my L275. I believe the loader is an L1730 based on my research but cant be sure because the tag is partly un legible.
Have not had much luck finding info regarding a torque spec on the bottom of the piston. Two questions, is this a critical torque or does it just need to be tight? And how to verify I have the correct loader model number so I can try to source a manual.

Thank you.

View attachment 54007

Most find it more cost effective to have cylinder rebuilding at a local hydraulic shop rather than trying to find seals, install them without putting a twist in them. Torque value would be more than just tight.

I have attached a couple of files which are generic to all cylinders.

Dave

 

[JR79]

Thank you for the links. Unfortunately I dont think those apply to my cylinders. As you can see in my picture above the piston nut is not a typical nut - it is round and a spanner wrench is required. I would think It would be difficult to get 200-300 ft lbs on a spanner wrench with a 10" long handle.....kinda at a loss on this.
The fact that it requires a spanner wrench leads me to believe there isnt a specified torque. But I really hate assuming.

Also the gland nut at the top, the one that is typically tighter than hades is not even threaded at all. It simply has a 1/8" rod that laces through the barrel around a groove in the gland for retention. I have done a few of these cylinders in the past, this style is a first for me.

Slot in barrel....

This 1/8 keeper threads through the slot in the barrel and arround a groove in the Gland assy... notice the lack of threads

 

[JR79]

FWIW, I have all seals in hand and one side complete minus the question on the torque for the piston nut. Your chart is pretty well in line with a book I have that calls for 175-200 ft lbs for a 3/4"-10 piston thread. But the book also shows the more traditional assemblies with a standard nut.....

 

[GeoHorn]

JR, why do you need to retorque the piston nut at all? Why remove the piston? Can’t you just replace the seals with the nut on the rod?

BTW, I have just removed the steering cylinder from my compactor-roller because it has a similar “Clip-ring” type of assembly and the parts are not readily available (a metal back-up ring which has to be cut to be replaced...and no replacement available....... so I ended up just buying a completely new cylinder of modern mfr instead.).

 

[Dave_eng]

Go to Kubotabooks.com and look in the Loader section at the L1200.

L1200

Manual says the L1200 is made for L series machines from L175 to L285.

Your cylinders look like the ones on the L1200

This manual describes how to tighten the compression nut which is the nut on the end of the piston rod.

Dave

 

[JR79]

JR, why do you need to retorque the piston nut at all? Why remove the piston? Can’t you just replace the seals with the nut on the rod?

The ID of the seals are 1-1/8. The nut is 2". The nut also just slightly compresses the packing before it bottoms out on the piston.

 

[JR79]

Go to Kubotabooks.com and look in the Loader section at the L1200.

L1200

Manual says the L1200 is made for L series machines from L175 to L285.

Your cylinders look like the ones on the L1200

This manual describes how to tighten the compression nut which is the nut on the end of the piston rod.

Dave

Thank you so much! That answers alot of questions. I was able to find an old used manual on ebay but it wont be in for several days, I had no idea those files existed.

Thanks again!