Scratched cylinder

I got a lightly scratched cylinder on a Tak excavator. Is there any way to repair it without having a new ram made? It is leaking right now not really bad but i would like to fix it before work picks up again?! I would hope to fix it myself if possible, got raped last time i had a ram made. How would you go about pollishing the scratch out and would you have to reseal the cylinder?? Thank you

you should be able to have it re-chromed

Good Timing...

I was just looking at this recently for a machine I was looking to buy.\

It really depends on how badly the piston is scratched. If you think it can buff out, the seal (a new seal anyway) will adapt to the slightly changing dimensions of the rod.

You will need to replace the seal pack on the end of the cylinder, which can be a pain - so get someone to help you if you haven't done it before. It's my understanding that you can just go and buy the new seals. Getting the end off of the cylinder can be difficult, I beleive you will need to make a special wrench to thread the end off, or jerry-rig something up. I am sure they would sell that as well.

If the scratch is through the chrome, I beleive that you have no choice but to dissassemble and have the piston re-chromed.

This is all anecdotal of course, never having done this myself, just what i gather from reading online and talking to a local dealer.

Refinish.

Hello.

If there is much of a scratch at all the only solution is to refinish it.
The reason being is that the actual contact surface is the chrome.
Polishing down past the chrome will leave you with metal that will flake off over time.
The hydraulic oil will seep under the chrome and decay, forming an acid that will just get worse over time.
If the scratch is bad enough you may need to take it to a machine shop and have them mill it down a touch than have the plating place build it back to size with chrome.
This is Much cheaper than a new piston.

My machine shop has stock sizes of chrome shaft in stock. They just cut the fitments off both ends and replace the chrome section. Pretty straight forward.

How deep is the scratch and does it have rough edges?
If the scratch is deep and smooth fill it with locktite metal filler and buff smooth.
just keep a eye on it the filler can come loose over time make sure you use a propane torch to bun off any oil before applying and clean well , If the scratch was rough and has damaged the seal you will need to replace it depending on how bad it leaks. its a lot cheaper to try to repair the scratch then recroming.
I have had good luck repairing the rod this way, I almost forgot pull the pin and rotate the rod eye 180 so the seal has new surface to seal against. If the seal has a little damage this can stop the leaking.

How deep is the scratch and does it have rough edges?
If the scratch is deep and smooth fill it with locktite metal filler and buff smooth.
just keep a eye on it the filler can come loose over time make sure you use a propane torch to bun off any oil before applying and clean well , If the scratch was rough and has damaged the seal you will need to replace it depending on how bad it leaks. its a lot cheaper to try to repair the scratch then recroming.
I have had good luck repairing the rod this way,it wont last for ever it will get you buy for a bit, I almost forgot pull the pin and rotate the rod eye 180 so the seal has new surface to seal against. If the seal has a little damage this can stop the leaking.

cylinder

watglen said:

My machine shop has stock sizes of chrome shaft in stock. They just cut the fitments off both ends and replace the chrome section. Pretty straight forward.

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I agree, this is the best way too go, Watglen, maybe you can give him a price, saying he was in your area and he will know what to expect in his area. I guess we need some measurement from him before you can do that.
I dont know about the filler idea, if I was working the machine on a job and that happened, I probrably would try it, but its a get by temporary fix only. As you stated you want to get it fixed now before the work picks up and thats a very good idea
Ive never had anything rechromed, but I was told it cost more that getting yours replaced by a machine shop
Example you dont fix it right and you get this great job and start it and you start leaking fluid on the ground, HUMMMM not good, if you get caught and they stop the job, then you are looking at either losing the job or spending twice as much to fix it right
Ive been there done that and Ive got scars to prove it

I have a six inch main boom cylinder on my knuckle boom log loader that had a big nick in the rod. So I cleaned it up then used starting fluid to get the oil and dirt off. Then made a had plastic U shape to fit the rod and used J B Weld and took the U shape curve to made it the same as the rod and it has been on there for years now.

Great info, i will try to fill the scratch and rotate the rod. Really appreciate it!

I know this works inside a cylinder with rust damage, so should work on rod. use acid core solder to fill scratch and smooth down to size. in a cylinder we just hone it back to size.

No problem glad to help

One of the rams on a loader I looked at a while ago had a long, deep gouge on a ram welded up. The seller showed me the repair; otherwise I would not have noticed it. He had hired a pro to do the welding. He told me the details of the type of rod they used and how they smoothed the surface afterwards, but I don't recall the exact details. In that case, it appeared to work well.

Once I was googling this type of repairand I found something that is done in the field like welding or resurfacing. From what i remember it was southern states area. I am sure it was not cheap. Showed them doing a big machine and saying how fast the repair was with not much down time for the machine.

I carry a fish hook sharpener stone. Lightly buff the high rough ridges on ethier side of the scratch- at right angles to the stroke. This will make the glan seal last a little longer.