Edit: If fluid is getting to that side of the piston, the piston packing is also leaking. There should be little, if any fluid up there. The "seal" around the shaft is probably nothing more than a dust wiper.
Jerry
Actually there is suppose to be oil on that side of the piston because that side of the cylinder also serves as the hydraulic reservoir.
When I replaced the seal on my '48 the one that came out was a leather lip type. The one I put back in was the modern double lip rubber type. And if I remember correctly there is enough room to put two of them in there, which I did so the outer one acts as a dust shield and better protects the inner one.
I also used a type of teflon rope that I wrapped around the flanged face of the cap to seal it to the cylinder when threaded back on.
What I find especially ingenious about this type of set up is that the outlet hole on the reservoir side of the cylinder also serves as the bypass. As the piston moves up the cylinder while lifting to the top past this hole, the pressure escapes though this hole and recirculates back to the pump. Pretty cool I thought.
Anyways, I hope your back feels better soon and back to working on your truck!!!
Paul.
