Cat excavator cyl leaking

[leaddog]

I just bought a cat ms120 excavator and it has a couple of cyl leaking. The packing gland has a wire ring on it. It looks to me like I should be able to tighten the packing gland but I can't seem to move it. I can't find a set screw or any thing holding it in place. Does the wire ring do something. Does any one have a breakdown on these cyl's? The rods are smooth and clean so I'm hoping I can get by with just replacing packing or do I have to rebuild them?
Thanks
leaddog

 

[wdchyd]

Leaddog,

You have a "Mitsubishi" Cat.......that ring is a lock ring to keep the gland from loosening, be prepared to do some real heavy duty torque work to disassemble this cyl......and the kit won't be cheap.....

Seen many competent mechanics fail at getting these apart successfully as the nut on the end of the rod is torqued "Extrememly Tight"......

This repack or rebuild will require special tools and/or cylinder torque bench just to remove the nut to expose the seals inside the gland head......and the chrome rod may have nicks and scars to be worked on if it's a bucket cyl....

It would be cheaper in the long run to farm the job out to a hyd repair shop (or Cat) with the cyl bench , it'll have to go back together retorqued back to specs to prevent failure from the nut coming off......which potentially will trash the cyl.....

I say this cuz I have such a machine capable of this in excess of 30,000 ft lbs of torque.......I've had some jobs of cleaning up botched jobs from DIY's and it's not pretty, costs more money than just farming it out.....

To the right shop it's routine........:thumbsup:

Here's a pic of our cyl bench (28' long).....It brings in BIG work....

 

[leaddog]

Thanks, I was hoping that I could pull the packing gland off and put in split packings and not have to redo the whole cyl. I'm a retired machine repairman and have done LOTS of hyd cyl and was hoping cat made them with split packings but guess that was wishful thinking. When I looked at the rod end and saw it was solid I knew the wiper seal had to go on from the piston end but the rod and wiper seal are good so I was hopeing!!!!!
I don't have a part breakdown on these so that is why I asked.
Guess , I'll take it off and take it in. Thanks for the info.
Yes this is a Mitsubishi cat. It's in really good shape but wasn't used much in the last few years and I think the packing got dried out. I wish I could get a manuel for it but I don't think they are easy to find.
leaddog

 

[wdchyd]

Yep, that's either yank it and do all the seals (and rod gland teflon lined bushing) or leave it alone and use it leaking.....

The piston head has to come off to get at the rod seals in this case....

Good luck..

Bill