8n PTO & Hydraulics

   / 8n PTO & Hydraulics #11  
Joel
The pressure relief valve is located on the hydraulic pump body, towards the rear of the tractor, maybe a half inch UNDER the PTO shaft. You really can't see it from the inspection holes with the shaft in place, but when the pto shaft is spinning, if it's leaking you can see turbulence in the hydraulic fluid adjacent to it.
Better access is obtained by taking the top cover off, the one foot by one foot casting under and behind the seat. This cover is somewhat heavy, maybe 25 pounds, but if you take it off, lift it straight upwards, and the only danger is bending the one foot long rod sticking down awkwardly below the cover and mechanism. Like I said lift the cover straight up till that rod clears the tractor and you'll be all set.
When you put the cover back on use a new gasket, because the hydraulic fluid is pumped up thru a passage in the main tractor body and into the cover--you'll see the hole on the back right where the two castings meet, and this will be under pressure when the pump is operating correctly maybe 2000 psi.

When the cover is off you can check the lift piston-- it has a leather--yes, leather--ring that stretches over the top of the piston and into a groove on the piston. If the leather is shot, you need a new one, because it needs to maintain the seal in the cylinder.

When you put the cover back on, the ball on the end of that awkward rod needs to be put into the recess of the mechanism on the side of the hydraulic pump, as you lower the cover that last half inch. Two people can help with this, as one slowly lowers the cover, and one feeds the rod into it's position feeling thru the right inspection hole. It's clever how it works, but that last half inch is awkward.
Get the I & T manual, there are pics to help you.
simonmeridew
 
   / 8n PTO & Hydraulics #12  
there is a newphrene backupwasher and oring available for the NAA piston, and you can still get the oem 3 steel ring piston as well.

some people find the neophrene backup washer easier to install, plus it is formed with a cup side to support the oring.

remember.. oring towards the colsed end of the piston.. backup washer to the open end of the piston... open end of the piston faces out o fthe cyl.. closed end faces into the cyl..

soundguy
 

Tractor & Equipment Auctions

Ferguson Rubber Tire Asphalt Roller (A52377)
Ferguson Rubber...
2017 INTERNATIONAL PROSTAR (A53843)
2017 INTERNATIONAL...
2000 John Deere 1860, 30ft Wide, Gandy Box, Wing Fold, 7.5in Spacing (A53472)
2000 John Deere...
2016 RAM 5500 Bucket Truck - Cummins Diesel - Auto Trans - 4X4 - Terex LT40 Boom (A53473)
2016 RAM 5500...
2010 Ford Edge SE SUV (A51694)
2010 Ford Edge SE...
2000 SCHWING P88 PORTABLE CONCRETE MIXER (A51247)
2000 SCHWING P88...
 
Top