How to remove relief valve seat from hydraulic control valve b6200/7200

[Clay T.]

Good Morning, I am trying to overhaul the relief valve in my b6200d 4wd gear tractor. I can get the spring, collar, poppet, shims all out of the control valve easily, but not the valve seat with the o-ring on it. Does anyone know how to remove the relef valve seat from the control valve body? Thanks. Clay

 

[TheOldHokie]

Good Morning, I am trying to overhaul the relief valve in my b6200d 4wd gear tractor. I can get the spring, collar, poppet, shims all out of the control valve easily, but not the valve seat with the o-ring on it. Does anyone know how to remove the relef valve seat from the control valve body? Thanks. Clay

I would try plugging the outlet(s) and then apply a little shop air to the inlet while holding a rag over the top of the valve. Should poppet (sic) it right out

Dan

 

[Clay T.]

I would try plugging the outlet(s) and then apply a little shop air to the inlet while holding a rag over the top of the valve. Should poppet (sic) it right out

Dan

Dan,

Thanks for the tip. Where that valve seat is located makes it very difficult to extract. Forgive me for sounding dense, but the seat has a hole in it where the poppit sits, so how will air pressure build up behind the seat to push the seat out? My other question (again very dense) would be where is the inlet that you would put the compressed air in to get the air behind the seat to force it out? Any help greatly appreciated. Thanks. Clay

 

[TheOldHokie]

Dan,

Thanks for the tip. Where that valve seat is located makes it very difficult to extract. Forgive me for sounding dense, but the seat has a hole in it where the poppit sits, so how will air pressure build up behind the seat to push the seat out? My other question (again very dense) would be where is the inlet that you would put the compressed air in to get the air behind the seat to force it out? Any help greatly appreciated. Thanks. Clay

Apply air pressure to the oil inlet and it will unseat the poppet. You may not even need to plug the outlet. If it is still on the tractor and the oil lines are connected use hydraulic oil to push it out. That will be messy so do it at lowest possible idle RPM, have a catch basin under the valve, and be ready to shut the tractor off the instant the poppet pops. Good strong magnet might also work.

Dan

 

[Clay T.]

Dan, We may be talking about two different parts. In my case the poppet on the relief valve comes out, but sitting further into the control valve body is a replaceable valve seat with an o-ring on it. The poppett cone sits in this valve seat. That valve seat with the o-ring is what I need to get out. Will the air pressure also dislodge that? Clay

 

[TheOldHokie]

Dan, We may be talking about two different parts. In my case the poppet on the relief valve comes out, but sitting further into the control valve body is a replaceable valve seat with an o-ring on it. The poppett cone sits in this valve seat. That valve seat with the o-ring is what I need to get out. Will the air pressure also dislodge that? Clay

My mistake - I thought you were adter the poppet. You may be able to pop the seat out with a small pick inserted in the center hole. Depending on how tight it is in the housing air or oil in sufficient volume might do it as well. Or if you don't need to salvage the seat screw a small tap into the center hole and use that go pull it out.

Dan

 

[#40Fan]

Grab a short piece of rubber hose and your wife's turkey baster. Stick the short hose on the baster, squeeze the bulb and push the other end of the hose against the seat. Release the bulb and pull the seat out.