3-Point Hitch slow rise, high rpm needed for 3 point hitch

oldnslo · Nov 17, 2016

Sassafras,
I just looked the service manual for my 2400H and it is a different style relief and the instructions simply say remove these parts. I can't tell by the picture but is there room to get a dental pick hooked under the head of the poppet and carefully pull it out? Another option if you can access a pressure port is use some compressed air to blow the poppet out.

Magnet might also work but be careful so that you don't magnetize the poppet. Then they turn into crud catchers. (technical terminology) ;-)

sassafraspete · Nov 18, 2016

Thanks oldnslo. I took the front face of the 3 point piston off (includes stop valve and inlet line and is what you do when you replace the 3 point lift seals) and was able to use your suggestion to force air into the fluid inlet and push to poppet out. This needs some restraint , as the air pressure will turn the poppet into a flying missle. Don't ask me how I know! The poppet looked clean. Since I was too lazy to take the whole seat platform off, I was not able to visually inspect the valve seat. There is not much room to work with if the seat platform not removed. Anyhow, I used compressed air to blow out some passages, hoping to dislogdge any gunk that might be in the seat.

While I had the stop valve assembly off, I took it completely apart and blew out passages.. It appeared to be clean. The stop valve itself, consists of a piston that has a chamfered end, that fits into a chamfered seat to seal off the flow. The back side of the piston (the side next to the rod end) has 2 o-rings that seal the piston to the walls of the cylinder it slides in. The piston is not connected to the rod shaft. When you turn the stop valve in (to the right), it pushes the piston (valve) against the chamfered seat and seals the flow. When you turn the stop valve knob to the left, it backs away from the piston. The fluid pressure has to push the piston back to the end of the rod...thus opening the passage. I am wondering if somehow this piston is not getting pushed back all the way...possibly due to worn o-rings. Although they looked ok to me, I may try to get some new ones and replace.

Anyway, having said all this.... what I have done so far has not improved the 3 point speed. I currently have the backhoe on...and it's speed did not improve yet. I plan to replace the o-rings on the little stop valve piston and see if that helps any. After that, I assume I need to look at the FEL joystick control valve. I keep hearing people talking about the detent and valves not centering. There are 4 valves/lines controling the FEL, an inlet line, outlet line, and a 7th line on one side that I assume is the power beyond (PB) side?

Anyhow, thanks for any suggestions/ideas.

sassafraspete

sassafraspete · Nov 18, 2016

Woo HOO.....OK, I finally found/fixed the problem. I hadn't tore into the FEL control yet, and this morning before heading to my "retirement job", I decided to take off the power beyond line and remove the fitting that looked to be something different than other fittings on the control. The fitting had a nipple on the end with a groove with an O-ring that was half gone. Being 12 miles from nearest hardware store, and without a handy box of assorted o-rings (I need to get this), I dug around in my assorted boxes of plumbing supplies and found a ring that worked. Reconnected the fitting and hose, and Voila. there you have it. So about a 1 cent part and 10 minutes of time, I could have had this fixed. I guess the consolation prize is that at least I learned a lot and with first hand experience in looking at relief valves, stop valves, and 3 point lift pistons and seals. Also, I just had a new paying job come up and it was contingent on getting this backhoe working properly.

Thanks everyone for the help. As usual , the Forum is great and gave me ideas.

sassafraspete