Dunham Lehr 22 loader cylinder disassembly

[ScottNC]

Had not encountered a hydraulic cylinder with an internally grooved tube before attempting to re-seal the rollback cylinder on a DL 22 mounted to a DB 885. Could not remover the rod and piston last winter due to the internal groove I wasn't aware of. I ended up $360 in the hole for a simple seal kit replacement at a local hydraulic shop. A lift cylinder is now spotting the floor and not wishing a repeat expense wish to know how to defeat the groove. I was told there is a half round plastic ring "tool"?

 

[DanielW]

I can't think any tool you mean for that style of cap removal. To be clear (because I can't remember ours): Is it the style with the internal groove for a steel wire/rod that you feed in/out through a hole in the side of the barrel that fastens the cap to the barrel? Or just a snap-ring holding the cap on?

Whatever the case: Is it really worth your trouble to re-seal? Especially knowing the previous seals have somehow torn themselves up within a year (which would cause me to suspect something else is up - a scored bore/piston, a slight bow/bend in the rod putting excessive loading on the cap, etc.).

We have a D/L #22 loader on a Ford 6600. When the roll cylinder went about 8-10 years ago, I just went to Princess Auto and purchased an appropriate brand-new aftermarket cylinder. Can't remember the size or cost, but wouldn't have been more than $250 CAD at the very most. No worrying about the condition of the old bore/rod/cap, no tearing apart, no sizing and sourcing a seal kit. Just a plug and play cylinder (might have required a couple of ORB to NPT adapters at a few dollars each, but no big deal).

I find that the case for the majority of my hydraulic cylinders that need work. Unless they're unique/custom, it's not worth the time to rebuild. Especially if the rod/barrel is at all suspect, or if they have the old-style vee-back seals. Just not worth my time when a new aftermarket cylidner is usually between $150 and $350.

 

[rrlund]

I'm thinking there's a set screw that you take out then push that end in to get to the wire ring isn't there?

 

[ScottNC]

rr, getting the wire out isn't the problem, it's getting the seals past the internal groove once the wire ring in removed.

 

[ScottNC]

Daniel, I am familiar with the style needing the wire removed through a hole. On my cylinders once the end cap is unscrewed the rod support can be pushed in far enough to remove the wire/snap ring.

 

[rrlund]

How far in is the groove? The service manager at a dealership told me one time that when you're installing a seal where there's danger of it rolling, cut a coke bottle so the hole in the tapered part is just the right size to slide on the shaft so it goes inside the back of the lip to keep it from rolling. Might not work in your case. I can't see what you're working on.

 

[ScottNC]

How far in is the groove? The service manager at a dealership told me one time that when you're installing a seal where there's danger of it rolling, cut a coke bottle so the hole in the tapered part is just the right size to slide on the shaft so it goes inside the back of the lip to keep it from rolling. Might not work in your case. I can't see what you're working on.

Less than an inch as I recall RR. It is obstructed by the piston as it is being withdrawn from the cylinder. The piston seals/packing snag on it.

Back when I was a 20's sprout in construction in the Rio Grande Valley (Brownsville, Harlingen and Padre Island) we had weekly cylinder leaks due to the sand that I tended to on Saturdays. Mostly Case, never saw a cylinder with inside the cylinder grooves. Later I bought a D4D dozer with leaking blade lift cylinders, again no problem. Maybe the use of internal retaining ring grooves is another example if British engineering? Dunno. They seem to have a propensity for looking at how the rest of the world does something then copying it by doing it differently. I offer as an example driving on the left.

I have emailed a supplier of hydraulic cylinder reseal kits looking for a solution (or the described-to-me plastic half ring) but CS being what it is these days, my question must have confused their AI response "staff". It's been right at two weeks without a response.

Scott

 

[DanielW]

Would a piece of shim-stock wrapped around it not do the trick? To act as a sleeve to get past the internal groove? Seals that have to slide past internal snap-ring grooves aren't exactly uncommon. Don't know that I've ever seen one on a cylinder, but I definitely have on a few hydraulic PTO assemblies. Don't recall it ever being a major concern. Either a piece of shim-stock used to get it over, or just make sure the edges of the groove are broken so it's not a sharp cutting corner on the groove, and work it over with some careful twisting and lots of lube.

 

[Phill Tibbetts]

I think it's called spending $300 to save $200.

 

[DanielW]

Maybe the use of internal retaining ring grooves is another example if British engineering? Dunno. They seem to have a propensity for looking at how the rest of the world does something then copying it by doing it differently. I offer as an example driving on the left.

Dunham Lehr was an American company. From Indiana, if I remember right. Later merged with Farmhand, then Farmhand was bought by Agco. And driving on the left came first (back in the horse-drawn days).

 

[rrlund]

Would a piece of shim-stock wrapped around it not do the trick? To act as a sleeve to get past the internal groove? Seals that have to slide past internal snap-ring grooves aren't exactly uncommon. Don't know that I've ever seen one on a cylinder, but I definitely have on a few hydraulic PTO assemblies. Don't recall it ever being a major concern. Either a piece of shim-stock used to get it over, or just make sure the edges of the groove are broken so it's not a sharp cutting corner on the groove, and work it over with some careful twisting and lots of lube.

Thinking about it a little bit, I wonder if you could just wrap a little wax paper around it?

 

[Jim.ME]

Thinking about it a little bit, I wonder if you could just wrap a little wax paper around it?

Thin brass or steel shim stock, like .005"to .010" maybe. If the wax paper tears during installation the remains will be in the hydraulic system, I wouldn't take that chance.

 

[ScottNC]

Dunham Lehr was an American company. From Indiana, if I remember right. Later merged with Farmhand, then Farmhand was bought by Agco. And driving on the left came first (back in the horse-drawn days).

Richmond, Indiana I believe a now deceased peach grower and lover of things David Brown told me. At one time there must have been a dealer as quite a few farmers south of me still use/did use David Browns, most had a derelict loader or two laying in weeds along a fence once the tractor got old and became relegated to the sole task of spraying herbicide. According to the hydraulic shop that took delivery of my half disassembled dump cylinder there is a tool for this. They were not forthcoming about sharing its source. Guess $360 for a rebuild trumps only $60 for the parts sale.

Daniel, Back in my college days (early 70's) there was an instructor who's tenure allowed him to keep his job regardless of whether he actually taught the course subject matter. Instead he would go on about worldly stuff - like drinking Aussie beer with Aussies during WWII, RR breaking an axle by dropping a wheel off the side of a mountain road and having the replacement arrive free of charge because, RR do not break axles - and, why the Brit's drive on the left. His story is that in the formative years of the automobile the Germans led the way. Early on they decided the hot exhaust and the fuel system should not be on the same side of the engine. Further the engine exhaust should not be on the same side of the engine compartment as the steering (and brake?) components. Thus, by engine design default the driver wound up on the left. I have repeated this story as true over the years but never looked into if it is factual.