Look what I found

Since the gasket kit I bought to R&R the pump assembly came with a new "O" ring for the ram piston, I pulled the piston this morning and this is what I found. Hard to believe it was lifting at all.

Here is the piston, has a few scratches but not bad.
Quick question for my memory...whats the position for the rubber and cork ring? top/bottom?

Thanks
Dennis

Put the new piston on your work bench with the DOME end up. Heat some water to boiling point, remove from heat. Put the leather backing ring into the hot water and let sit for about 20-30 minutes [until the leather is plyable]. The leather backing ring has a smooth side and a rough side. After the leather backing ring is plyable, carefully slide it down the piston into the groove with the ROUGH side UP. BE VERY CAREFUL,THEY WILL TEAR IN A HEART BEAT. Next, oil the rubber "O" ring and slide it down the piston into the groove on top of the leather backing ring. DO NOT ROLL THE "O" RING ONTO THE PISTON. You can use a brake cyclinder hone to polish the cylinder. If there are deep scratches or gouges in the cylinder, replace it NOW. Don't forget to replace the three gaskets that go under the cylinder when re-installing.IMHO don

I think he says it preety good..... ....Dell

I did as you discribed and I gotter back together this eveving, she's work N Great!

Thats my youngest son...he thinks he knows everything

Thanks to the ZANE's post in 3/00 here's what he says.

Just always remember that the back up washer goes on the opposite side from the oil.It is so the O ring will not be cut on the sharp edge of the piston ring gland when pressure pushes it toward the ram rod end of the cylinder or the open end of the cylinder.