hydraulic piston rings

[seanpaintsflames]

In an attempt to rebuild the hydraulic lift controls and whatnot under the cover of the 53 Jubilee, I've got everything apart and covered in 90w goo on the table. I was expecting the pop the hydraulic piston out and find a leather ring, but mine has the 3 steel rings instead. The cover gasket kit I got came with what looks like a rubber seal for that piston, but just one of them.

What is the common replacement to this? I've heard leather and neoprene mentioned, but I don't know what I should be doing.

The reason I'm rebuilding is that I had to hold the draft control down to get the lift up, but them it would slam down as soon as I let the control lever go. I figured that I would just go ahead and replace all the seals that came new in the lift cover kit while I was in there adjusting things correctly.

Also- is there a good online walkthrough or explanation of this rebuild process? Thanks!

 

[carlntexas]

PO must have put an 8N piston in there it should have single neoprene and backup washer.

 

[seanpaintsflames]

Well, now I'm waiting for a new NAA piston with the neoprene ring to show up in the mail. Just a little at a time! At least it's cold outside and the grass isn't growing an inch a day.

 

[Soundguy]

ps.. if the stuff was covered with 90wt goo.. then you have a problem.

the hyds on a NAA use UTF fluid.. not the 90wt that the 8n did.

if the intersump sel the pto shaft passes thru is gone.. rear end fluid can mingle with hydro fluid.. if so.. use utf in both cases.

 

[seanpaintsflames]

if the intersump sel the pto shaft passes thru is gone

what is this?

In my inexperience, I may have misidentified the fluid. I just figured that's what it was because it smells like 80-90 gear dope. It's a grayish-light brown, smells like dog butt... ? I don't know. And I think the same fluid came out of the lift and the rear end housing. The lift fluid may have been darker.

 

[Soundguy]

on a naa well.. all the 53-64 machines ) equipped with hyds and pto, there is a seal between the hyd sump, and the rear diffy sump.. the pto shaft passes thru this sump on the way to the back of the tranny coupler.. if you pull the pto shaft you will notice a boss for the seal to ride on.

the seal can wear or over exuberant people removing or replacing the pto shaft can damage and hog the seal out, and then you can get mixing of the rear end and hydro fluids.

ALSO.. some former owners may have simply been too cheap to buy the owners manual and instead put gear oil in all the sumps becauses that's what 9-2-8 N series took, or they got bad info from other people that were too cheap to buy the manual.

UTF is what really should be in the hydro sump. Plain hyd oil COULD go in there.. but I would advise against it for the reasons stated re: leaky seals.

safest bet is to use UTF fluid in hyds.. then if it does leak into diffy.. it may dilute the viscosity.. but will still be a suitable fluid for final drives and such.