Ark 550 Cylinder Repair

[brandonozz 168]

Has anyone ever rebuilt a/the hydraulic cylinder(s) on a ARK 550?  I'm in the process and looking for some part numbers for the o rings, backup rings and outer seal.

Thanks in advance,

Brandon

[JamesBe1 80]

I haven't had to do it yet, but I have a couple of leaky cylinders.  I kinda figured that I would just take them apart and see what there is to see.  I have an o-ring kit and I plan on just replacing every oring that I can find.

 

I'd be interested in some pics and a narrative of your experience.

[brandonozz 168]

Well here is what I have so far.  Let me start by saying I am not a hydraulic guy and have never pulled a cylinder apart before so if my terminology is incorrect I appoligize.  If you are a hydraulic guy (girl) feel free to share any pointers.

 

My first problem was getting the end cap out and I was a bit worried because I had no idea how to get it out.  I thought the end cap would screw out with a spanner wrench but after turning it it didn't do anything.  You will notice the slot just above the end cap in the first picture. 

 

Here is a picture after the end cap is removed with rod, piston and end cap.

 

In this picture you will see a close up of the piston and the retaining clip that has to be removed from the slot to get the end cap out.  Not sure you can see but the clip has a 90 deg. bend on one end that will sit in a hole in the end cap.  This is used to drive the clip out or pull the clip back in during reassembly.  You will need to get a narrow tool like a screwdriver to get the clip started out.  A spanner wrench can be used to turn the end cap but I used channel locks over a rag and it turns fairly easy.  Turn the end cap until you find the two ends and then get the screwdriver under the loose end and turn to get the clip to "peel" out.  Once you get it out  a bit you can remove the screwdriver as the slot is tapered.  Removing the locking nut will get everything off the shaft.

 

Here is a picture of the end cap. 

 

 

End cap will need an O ring and backing ring on the outside sealing against the case and an O ring, backing ring and wiper/dust seal on the inside to seal against the shaft.  The piston has an o ring and two backing rings.  There is also an o ring on the shaft under the piston but I'm not replacing mine as it was pretty tight to get the piston to slide off the shaft so I think it's in good shape.  This loader hasn't been used for more than 5 years but the oil inside still looked pretty good.  I hope the oil in the uprights is looking good as well.  Been a few months getting the trans rebuilt and the loader is the next step.

 

[KC9KAS 4,741]

Thank you for the narrative and the photos.

I have an ARK 550 and will some day need this information......Now if I can just remember it!

[JamesBe1 80]

Thanx Brandon.  That's some great stuff. 

 

You probably saved me a couple hours of scratching my head and swearing at it trying to figure out how to get it apart - if I can just remember it too!

 

What do the wiper/dust seals look like?  Are they standard o-rings or something special?

[953 nut 51,775]

   Never have had to work on a hydraulic cylinder but you have removed some of the mystery involved in it.                

 

 

[brandonozz 168]

James,

I definately was scratching my head when the end cap didn't come out when I started turning it      I knew the slot had to be there for a reason it just took me a few minutes to figure it out. 

The wiper seal fits into a recessed groove in the end of the end cap.  To replace you will have to pull it all apart to get it installed.  My seal is toast and falling apart (likely a contributing factor to the o ring wear) but it looks similar to any oil seal but without a spring.  The seal is "L" in shape with the sealing surface 50% wider than the part that fits down into the recess.

 

Sorry the parts in the first pics were dirty - I snapped them before I cleaned them up.  Here are a two more including the O ring under the piston.

 

I'm not sure how important it is to replace the backing rings but I'm going to look for some.  I guess its going to be a manual search as I haven't been able to find any numbers on the interweb for the parts so I can cross-reference.  Not much parts information out there on these cylinders from what I can find. 

 

 

[KC9KAS 4,741]

Maybe you can locate a hydraulic cylinder repair shop to help you out.

[gwest_ca-(File Mod) 10,503]

Did you see the Ark manuals in the manual section here? Do a search for Ark and they will come up.

 

Garry

[brandonozz 168]

Did you see the Ark manuals in the manual section here? Do a search for Ark and they will come up.

 

Garry

 

Garry,

I had looked at the manuals and I see they had a replacement O ring/seal kit but no parts listed for the kit.  I figured I would need to go hunt the parts and do the best I can.

 

 

Maybe you can locate a hydraulic cylinder repair shop to help you out.

 

KC9KAS,

Well I took your advice.... Kinda.

Both of the major seal suppliers in Tulsa were closed today so I called a hydraulic cylinder repair shop.  He confirmed both shops were closed as he had checked also.  He was a great guy and offered to try to match the parts with what he had in stock so I went over to give it a shot.  The good news.... he said the backup rings next to the O rings are only there to support the O rings on the pressure side and didn't need to be replaced.  He found both the outer O rings and the one inner O ring and even found the seal for the 1" shaft.  The bad news is that I didn't get any part numbers to list here for reference but I think anyone could match up what you need at a seal distributor like Sealco or Crown here in Tulsa. 

I got to say, this guy knows his cylinders!  I asked about wear on the inner sleave of the cylinder and he said he doubted there would be any problems so thats a good thing.  He also said this type of cylinder is easy to work on as long as you don't break the "90" on the retaining clip when your trying to get it apart.  If the "90" breaks when removing the clip you will likely need to take to a shop that can get it out costing you some $$$.  So, when you first start turning the end cap preparing to get the clip out I would soak the groove with some PB Blaster if you find too much resistance in the event the clip has rusted to the outer case.

This "old timer" not only found my parts but installed them in the piston and end cap and wouldn't even take my money!  That is the type of place I will spend my money when I need some work done!

[MalMac 1,328]

brandonozz, thanks for your post, My Ark is heading down the same road. I tracked the guy down that owned Ark Loaders, he is still in business making bigger loaders for big tractors. I sent emails and called the company but could not get the guy to return any correspondence. That was a couple of years ago. Guess he has no interest in his past products.

[KC9KAS 4,741]

Glad you found the information on the cylinders and got them put back into shape!

[brandonozz 168]

brandonozz, thanks for your post, My Ark is heading down the same road. I tracked the guy down that owned Ark Loaders, he is still in business making bigger loaders for big tractors. I sent emails and called the company but could not get the guy to return any correspondence. That was a couple of years ago. Guess he has no interest in his past products.

 

You know, I've only been playing with Horses a couple of years now so It's nice to be able to contribute to the forum/all you great guys who have helped me out in the past.

 

 

 

Well guys, I got the cylinder back together and on the loader.  Installed a new belt on the pump and  got the pulley on the pump adjusted to align with the PTO.  Had the loader out behind the garage so I fired up the 200 to go get it and hook up for the first time. 

The PO had the loader out in the pasture for 5+ years after the trans case cracked and didn't know how to fix it.  Hooked up the loader and cleaned the quick connects and fired her up.  It took a while for everything to prime in but finally things started to move a bit and then..... smoke everywhere!!!

Blew a hose and the oil sprayed on the mufflers and engine.  I knew the hoses were junk from sitting outside and planned on replacing them but I wanted to get it in the garage so I was just trying to get the loader off the ground so I could move it.  What a mess.  So..... I can't report on the seals and if they will leak or not but hope to get some new hoses early next week and see how it performs.  Took a look at the other dust/wiper seals and they are junk as well so the other three cylinders will be getting rebuilt very soon also.

 

Does anyone see a problem with de-greasing/washing the engine?  Anything I shouldn't get wet?

 

I knew this was going to be a challenge with my skill set so I'm learning as I go.  Fix one thing, then on to the next, then the next..... enjoying it though!

[JamesBe1 80]

Hahaha.  Fix one thing and another breaks.  Sounds like you are taking a page from my playbook.  Don't give up, you will get there and learn a lot along the way.

 

There are several degreasers on the market.  Pretty much all of them will loosen/remove paint.  I would spray it down with some purple-power or other degreaser and wash it off with the hose.  I wouldn't worry too much about getting things wet.  Just done spray the reg/rect and force any water into the breather.  Other than that, you should be fine.  Of course, that is my opinion, not my advice.  I very often spray down my engines and try to be mindful of the things I mentioned.  Also, try not to do it when the engine is hot.  You run a high risk of cracking the block.

 

After you are done, get it started again and make sure you bring it up to temp for a while to boil off any water.

 

I am sure that you are going to get lots of opinions on washing the engine.  That was my 2c worth.  Good luck.

james

[KC9KAS 4,741]

I just checked my cylinders on my 550, and all 4 of them have an internal snap ring on the rod end.

[boovuc 1,090]

Well that should keep the mosquitoes under control for a little bit!

[brandonozz 168]

I just checked my cylinders on my 550, and all 4 of them have an internal snap ring on the rod end.

Are you saying they are like mine or are they made different?  

 

 

 

Well that should keep the mosquitoes under control for a little bit!

LOL, not as bad as the mosquitoes are around here right now.  We had steady rains and the ditch across the street wasn't draining and there were millions swimming in the ditch.  That was actually the first task I gave to the 200.  Had a breaking plow and fabbed to a A frame for the 3 PT.  As soon as the ditch dried up enough I got in there and ripped a ditch to get the water to drain.  Got to love hydraulics.... when the hoses don't break!

 

Since all the hoses are off the loader and the lines are drained down I think I'm going to pull the other 3 cilinders and go thru them as well as their wiper seals are junk at a minimum.  Even if the O rings are good for now it probably wont take long for them to get damaged without good dust seals.

[JamesBe1 80]

 

I just checked my cylinders on my 550, and all 4 of them have an internal snap ring on the rod end.

Are you saying they are like mine or are they made different?  

 

 

 

 

Mine have snap rings also.  They are not original at all.  They are 2500PSI (i think).  Much larger than the standard cylinders.  I suspect that they move slower than the regular ones, but it's not like speed is important in this application.

 

One of the things that bugs me about these loaders-  When you have it level with the ground and you scoop up material, there is no way to tilt the bucket back further.  The only way to carry a full bucket is with the assembly raised high.  Definitely not a good thing on anything other than flat level ground. 

 

Anyone else notice this?

[KC9KAS 4,741]

Are you saying they are like mine or are they made different? 

 

Mine ARE NOT made like yours.

My cylinders do not seem to be exceptionally large diameter, nor exceptionally small diameter, so mabe they are original?

[MalMac 1,328]

JamesBe1, I agree with you all the way. They need to till back more than they do. I have run Pay loaders and big farm tractors with buckets and it was hard to get used to the way the Ark tilts back. If you don't carry it high you won't have any material in the bucket. Also if you are hand loading material with a shovel or pitch fork or whatever you have to have it high enough so material does not fall out. Most defiantly a dangerous situation trying to move any distance and keep a bucket full.

[JamesBe1 80]

Mine are definitely not oem.  Dunno where along the line they were installed, but they bear no resemblance to any of the others that I have seen.

 

I can't say if yours are oem.  How closely to they compare to any others you've seen?

[JamesBe1 80]

JamesBe1, I agree with you all the way. They need to till back more than they do. I have run Pay loaders and big farm tractors with buckets and it was hard to get used to the way the Ark tilts back. If you don't carry it high you won't have any material in the bucket. Also if you are hand loading material with a shovel or pitch fork or whatever you have to have it high enough so material does not fall out. Most defiantly a dangerous situation trying to move any distance and keep a bucket full.

 

Yeah, I almost rolled mine once.  Didn't make that mistake again!  I felt it start to go past it's tipping point on less then level ground, and between shifting my body weight and dropping the bucket, I was able to save it.  That's as close as I ever want to get to learning the limits of these things.

 

I got mine for the purpose of scooping up piles of horse manure in the small pasture where we keep the horse.  Turns out that the D's rear wheels will spin before it can break through all the plant growth around the manure (plants love manure).  These are liquid filled ag's, and I still couldn't get enough traction. 

[brandonozz 168]

Well guys I got the new hoses installed and it works great.  I decided to try out the loader a bit and get/make the right tool before I rebuilt the other three cylinders.  Started to turn the retaining clip out but I had resistance so I decided to wait until I get a good spanner wrench so I dont gouge up the end cap with channel locks.

James - thanks for the advice about moving with the bucket low.  I hadn't thought about turning it on it's side but will definately keep that in mind.

Brandon

[brandonozz 168]

Got the D 200 out two days ago and went down to my neighbors house to help him move some compost. Two or three buckets in I had another seal fail and started leaking badly. I had only had time to get one of the cylinders repaired this past summer and knew I was on borrowed time. I used the loaded several times thru the summer with no leaks but the cold weather had it's way with the old brittle seal.

One thing of note from the teardown. I relayed some information previously in this post about the backing rings for the "O" rings that had been told to me by the hydraulic repair guy. He said that they didn't need to be replaced as they just support the "O" rings. I will now disagree with him as that is exactly the part on the piston that failed and I would replace with new if they show any signs of wear. The seal supplier where I picked up my new parts recommended different types of seals for the piston and shaft seal and said they were much better than the "O" rings so that is what I bought and figured I would give them a try. Note the "T seal" for the piston is almost shaped like a tri rib tire and the backing rings come with the T seal as a kit and are split for getting them in place easily. These seals are made of a harder type of plastic except for the wiper on the outside of the end cap which seems a bit softer. The seal on the outside of the end cap is a standard "O" ring with a backing ring.

Please note I was buying parts for three other cylinders but they didn't have everything I needed so the quantities are not correct for what you need. Here are a few pics with the invoice for part numbers

 

I'll get these new seals installed and report back if I have any problems.