The Stovebolt Site Forums The Parking Lot Big Bolts Hydraulic cylinder

Does anyone happen to know where I can find the rear seal for my big hydraulic cylinder, the one in between the frame to lift the bed? It is on a 1963 chevy c60. I am not sure who makes the cylinder and I am pretty sure that it is stock.

is it a welded cylinder or does it have a threaded ot bolt-on cylinder head? There is a reason I'm asking.

Also, what are you calling the rear seal? There is only a piston seal (probably a cast iron piston ring) and the rod seal. So one is inside and the other is at the top. Most of these old twin arm cylinder had welded bases.

I pulled my rod seal and headed to the bearing/seal shop in town. If I recall correctly I ended up using a seal for a Chevy timing chain cover. It wasn't as thick has the seal that came out so I ended up installing 2 of them.

The seal I am talking about is around the rod so I am guessing a rod seal? I think the cap is threaded as in I did not see any welds at a quick glance.
Jrpontiac: I live in a small town so the closest bearing/seal shop is over an hr away

dealing with farming and logging you don't have anyone around that does hydraulic work??

Bill

Surprisingly not anymore. Carquest used to do all of our log truck and large equipment work but then oreilleys bought em out. Now oreillys doesnt carry any parts for anything over 1 ton, not even in the catologs. Napa does my tractor work for hydraulic hoses and couplings and the smaller cylinders but that is about it.

Good news..it has the threaded cap. That means it's rebuildable w/o machining the cap off. Here's what to do:

1. raise the body and securely brace it with some heavy timbers of say 6x6 size. Lower the body onto the timbers and when your absolutely sure the weight of the body is resting against them and there is no pressure against the cylinder you may proceed.

2. Remove the cylinder rod end from the hoist mechanism. This may be bolted or pinned but however it is take it loose making sure the cylinder is supported below. You may want to completely remove the cylinder as many are uncomfortable working under the raised body. I've done it both ways so I understand the reluctance of many to work there.

3. When you have access to the rod seal/cyinder cap remove it and take it to the clean part of your workbench. Remove the seal w/o damaging it or tearing it up.It will likely have a small stamped number on it that can be used to cross-reference it to some available brand.

4. If you cannot find it locally then almost any seal can be found and identified by dimensions alone. This is probably available on the internet as nearly anything else is. Just measure the ID, OD and depth.

5. When you have the new seal use a reverse procedure to re-assemble the cylinder and re-connect to the hoist and the hoist to the body. Make sure the cylinder rod is clean and free of debris. Lightly oil it before replacing the seal over it. Same with the cylinder head where the seal goes but that goes w/o saying. So why did I say it? Because dirt, contaminates and scratches will ruin the new seal as it has the old one.

6. It would be a good idea to drain and replace the hydraulic fluid in the system while it is down. Dirty oil, water and air in a hydraulic system will kill it quicker than you can say Jack Robinson. Cycle the hoist several times with the body connect to make sure all the air is bled out. Likely there is a small bleeder on top of the cylinder at the rod end much like a wheel cylinder bleeder.

7. Be careful and exercise good judgment and check yourself twice.

8.Your now done. Go enjoy your new truck. EZ as that.