Repacking/rebuilding a cylinder

[gemini5362]

It's dollars either place.

Unless I misunderstand, both KJM and john_bud have mentioned a wrench that enganges holes on the side of the cap. My cylinder caps don't have holes, just two round sides and two flat sides. These are fairly small cylinders, 2 1/8" from flat side of the cap to flat side of the cap.

As for a pipe wrench, I'll take the cylinders to the dealer and get them repacked before using a pipe wrench. I've found service/pump wrenches that size (around $30), but I'm not sure they'll work. The other options are a regular wrench or a large adjustable wrench which would both be around $100.

You are correct they are talking about spanner wrenches. These look like a wrench with two pins sticking out on one side. The pins go into holes in the cap and engage the holes allowing you to put pressure on the cap.

What size wrench does the cap need. 100.00 seems pretty steep for a crescent wrench or even a huge wrench. why dont you try to measure it and see what size it is then go to an auto parts store and see if they have something big enough to fit. Autozone, O' reillys, Napa all have free tool loan programs. You pay a deposit on the tool then when you return it they give you your deposit back

 

[chanceu]

Have you been successful finding spanner wrenches?.I am also looking for something to remove the "round nut" on both my loader cyl.Mscdirect has about200 different ones

If your question is directed to me, I have not found anything I can use yet. However, I don't think I need a spanner wrench. If I understand what a spanner wrench is, it comes in two varieties. One is a face spanner which is used when the holes/slots are on the face or front of the nut/cap/pulley and the other is a pin or hook spanner which is used when the holes/slots are are the side of the nut/cap/pulley. I've seen both in fixed and adjustable sizes. In either case, the pin holes/slots are required for the spanner wrench to work.

In my case, there are no holes or slots in the cylinder caps. My cylinder caps are simply round with two flat sides opposite one another. I assume I'll either need a big adjustable wrench or a 2 1/8" open end wrench.

 

[chanceu]

What size wrench does the cap need. 100.00 seems pretty steep for a crescent wrench or even a huge wrench. why dont you try to measure it and see what size it is then go to an auto parts store and see if they have something big enough to fit. Autozone, O' reillys, Napa all have free tool loan programs. You pay a deposit on the tool then when you return it they give you your deposit back

I need a 2 1/8" wrench. I've only looked a couple places, but all the open ended 2 1/8" wrenches I've found were around $150. The smallest adjustable wrench I've found that will handle 2 1/8" is a 24" and not all of them do. Northern Tool has a set that includes a 24" wrench for $49, but neither their web site nor their catalog give the maximum capacity of it. Crescent and Armstrong make one which run around $120. I've found a couple for around $50 that say they'll handle 2 1/8", but when there's that big of a difference in prices, I tend to doubt specs I find on web sites.

I did think about a tool rental/loan place, but I haven't checked in to any yet. I'm going to call around this afternoon to see what's available.

 

[tommu56]

chanceu

I've made a similar wrench out of a old broken truck spring.
Just lay out 2 parallel lines the with of flats grind inside lines a little do it slowly and keep cool cut out center in the same way finish up sides keeping them square to face and keep trying on part for proper fit.

tommu56

 

[chanceu]

I've found my solution. Northern Tool has a 24" (2 5/8" max) adjustable wrench. There are 3 Northern Tools within 20 miles of here and at least one has it in stock. It might be a big POS, but for $24.99, if it lasts long enough to remove and tighten these 2 caps, it'll be worth it.

 

[638]

Try putting the nut in a vice, clamping on the flats, standing it upright. Stand on the workbench and turn the cylinder with a bar through the boss on the other end.

ron

 

[bones1]

I gave up on finding spanners locally but I did find a big aluminum pipe wrench and the nuts came off very easily.

 

[KJM]

Yeah, we all have used pipe wrenches .... but.... they are really not the first choice in tool. A pin wrench can be had off e-bay for 20-30 bucks.

Issues with pipe wrenches are the obvious teeth marks, and the less obvious but more serious distortion of the cap. This only occurs when a 400 pound (that a 180 kg gorrilla for you Ozzies...) puts the cap on. A pipe wrench will squeeze the thing it is working on and if you apply enough force (3 foot breaker bar - 1 meter Ozzie!) it will put a lot o squeeze on and can deform the cap enough that you may have to spend some $$$ on a replacement.

G'day!

jb

Quite so - the distortion of the cap would be an issue if the cylinders are small. The ones on the backhoe are solid - distortion was one of the things that made me do a search-for-the-right-tool first. I really should have said that up-front - well spotted, that's a real concern.

I weigh in at under 80kg, with my cheater bar I figured the torque being applied was OK

Hunting down specialist tools here in Oz is both painful and expensive. Probably due to the less than 1/10th the population of the US and an area the same size - population density makes it uneconomic for people to carry whacky tools. Hopefully we'll get a nice bunch of on-line suppliers who can retail stuff quickly and cheaply! In these post 9/11 days, I'm very reluctant to bring tools back from the US in my check-in luggage. Gets kind-of hard to explain at immigration..

Anyway, G'Day to you too!

Cheers
/Kevin

 

[KJM]

I've found my solution. Northern Tool has a 24" (2 5/8" max) adjustable wrench. There are 3 Northern Tools within 20 miles of here and at least one has it in stock. It might be a big POS, but for $24.99, if it lasts long enough to remove and tighten these 2 caps, it'll be worth it.

I read this before I left work today and called in at our local tractor place. Had a look at all the cylinders I could see - and I found a couple with that kind of end. I asked the service guys what they used to remove them and they plonked down a Bahco adjustable. So there you go. Bigger adjustables seem to be proportionally stronger and the insane amounts of play matter less - so I'd guess your $25 is well spent. (and it can double as a hammer )

The other thing they showed me was their home-brew pin drive wrench. Very simple - it is a steel bar with a hole in one end into which an appropriate high tensile bolt fits (appropriate for the pin hole). There is an "arm" too - another smaller piece of bar with another pin-drive and this is bolted to the main bar in a "Y" configuration - the bolts that drive the pins are at the ends of the "Y". You grab the stem of the "Y" and away you go. This tool was made in the early 1970's and is still being used today, so it clearly works "just fine". I'm trying to figure out how I can fab something along those lines for the external (around the rim) pin drives on my cylinders...

Cheers
/Kevin

PS: responses are always 12 hours late (sorry!) - I'm on the bright side of the planet when your side is dark...

 

[MJPetersen]

The last(!) thing - you should be able to pull the rod/piston from the cylinder by hand (slowly). If you can't - be careful when you reach for a compressed air gun to "assist". Don't ask about that


Kevin, I cannot help but ask how far across the shop the rod and piston shot when you gave it a bit of assist air. I really laughed when I read that. Think potato gun with hydraulic cylinder.

I got to thinking of the 50 ton Grove hydraulic cranes that we had to replace the extension boom cylinder seals in. I forget now what the diameter of the largest piston(a telscoping hydraulic cylindar and rod) was (I am thinking 6-8 inches.) We had one stick and then come out rather, huh, forcefully. No real damage to the shop wall though.

We had to rig a dingle berry brush on a long rod with wooden carrier bearings to hone the thing. We had to replace the packing because they could not take the -50 and colder temps in Prudoe Bay without leaking and that is a no-no in precise work like bridge building when you have men working around the load.

Mike