I have a leaky cylinder on the tilt part blade of my D3. It was dumping oil pretty badly and I got it tore down but the rod looks to be bent. I am wondering if they can be straightened? I am taking it a cylinder shop next week but am anxious to know before then. BTW, it was a tough one to get apart, I left the reservoir end attached to the machine as I couldn't get the pin on that end out. The threaded end was tight as could be and after I got it off I ended up using the pickup to pull the rod and seals out of the tube as it was in there real tight for some reason. This is the first time I have tore down a cylinder. Thanks.
Straighten? I wouldn't bet on it. Also looking bent and being bent are two different things. Set it up between centers and check it with a dial indicator. That will tell you how straight or bent. So did you every get the clinder body off the machine? You will need that too as it has to be honed to clean up the bore when the cylinder is rebuilt.
In the past we had no good luck straightning out a bent rod. You might take a good look at the head to make sure that bent rod did not damage it too badly. Had bucket tilt cylinder on a 416 B a few years ago that got bent and it destroyed the cylinder can and head. Total loss. Good luck.
Rods can be straightened in a machine shop set up to do that with an expert doing the work with the right guages and other tooling. But a D3 rod is way to small to fool with. Toss it and buy a new or good used one.
I was able to get the rod over to the rebuilder today and he says he will need to replace it. It was bent. They will cut the eyelet end off and then weld on a new rod, say it is common procedure. Not sure how the reservoir end is gonna work out but at this point I am gonna get the rod replaced, reseal it and see if that fixes it. The pin is gonna be a real pita to get out if indeed I do need to take the entire cylinder off. I soaked it in WD and used my big air hammer on it and it would not budge a bit.
If you don't hone the cylinder housing you are wasting your time. Not doing so will damage the new packings on the piston head. Try some heat from a torch on it.
I have resealed MANY hydraulic cylinders in the field without honing the barrels, and have never had a complaint. If a visual inspection shows any surface flaws on the barrel wall, then yes you need to hone it. Get a bright light and inspect it good, and if you dont see any problems, I'd use it as is. If you take a cylinder to a hydraulic shop, they will hone it every time, whether it needs it or not. I understand that because they have expensive machinery they have to pay for. Honing really is the best way to go, but to say it is absolutley necessary in every case is, in my opinion, just not true.
Good advice bolthrower. We had some 992D's that I packed the cylinders myself 8-10 times over a period of 12-14 years. Never pulled the can until the pin bores got worn out. Those machines were running 20 hrs. per day 7 days a week.