First you need to determine whether the cylinder is the problem (oil getting past the piston, allowing it to drift) or the hyd valve is at fault (bad/worn spool valve or o-rings).
Two very different repairs.
I checked it pretty close Steevo, really believe it's the cylinder that is at fault. I've rebuilt cylinders before but don't know if a kit or parts are available for this little rascal. Some info from someone that has had one apart would be helpful.
I have rebuilt one on my 1225 but it was years ago and the dealer I got the part from is no longer in biz. It is very easy. The hardest part is getting the fittings out and then pulling it apart. I believe it consists of 2 small seals and one smaller o-ring. No fear, just might be hard to find the parts. Contact sonny's or sam's bolens. Both are in Indy.
Some of the smaller cylinders have a rod-end cap that is kept in place by the fitting that the hydraulic line connects to. If that is the case, there will be no holes in the cap on the rod end for a spanner wrench to turn it. For these, you just remove the fitting, and with the cylinder drained of fluid, you clamp the rod eye in a vise and pull the cylinder body off of the piston.
Sometimes that is harder than it sounds, and you have to persuade it.
Thanks Steevo, believe I have that type of cylinder. Talked to a friend in Oregon yesterday and he has a couple of spare cylinders I've swapped him out of so, for now at least, the rebuild question is moot.