Combines N 7 Hydraulics

[NDDan]

Rarely put flow meter on system. You could tee 3000PSI plus gauge into output line on pump. I'd say normally you would see 1200PSI hear while not running any functions. 2500PSI when steering hard. 3000PSI when a lifting header to end of cylinder stroke and a bit above idle. After getting your readings hear I would report back in. While doing your testing you should have it warmed up. When warmed up I would crank hard on steering to see if header comes up normally. Problem with header lift is normally in master valve. Could be orfice out of place, seat for earlier style power steering relief broke and or oring for seat blew, or number one solinoid not energizing when tring to lift head. At any rate problem is normally in that front valve which is master valve. Very rare to have pump problem but that would be next if all else fails. If your flow tester is built to take full system pressure at inlet and outlit you could put it in line with pump output. You would normally see 6GPM which is feeding steering and hydro charge when not running other functions. See what you find out. Good luck

 

[Rig]

Did more testing today. I teed a gauge into the compensator hose. It took forever to get the system to screw up but when it did the gauge was showing maximum psi(~3000) and was lifting the head very slowly. When things were going good head was taking 1800psi to lift but the system also briefly went to max before lifting normally then to max at ram limit like it should. Restriction in valveIJ When working normally, why the brief max psi before it starts liftingIJ Occasionally, you can feel the system hesitate then work normal. Compensator hose looks terrible and I was wondering about restriction in hose but I don't see how that could cause these sets of problems. Guessing problem in valve even though dealer worked on it and changed nothing. Hope this site tolerates repair questions!!!

 

[NDDan]

I think your right about restriction in valve. Spike pressure when first lifting may be what you would normally see to get head moving. I strongly feel you have pressure available to header lift valve beings you are seeing that pressure at compensating line. I assume auger swing is normal as well as power steering. When header rate of raise is slow operating power steering does not change that rate of raise does itIJ I'm thinking I would check with dealer to see if he tore down raise side of valve. I would want valve removed from stack so I could check solinoid operated pilot check which includes oring for needle seat and contaminates sticking armature. Next and more likely I would check oring that seals OD of second stage poppet and oring on the seat for second stage poppet. Some of them second stage poppet seats were locited in so if it don't come out it is likely OK. Don't overlook that seat though because it could be loose in there witch will allow it to move with poppet which will give you these symthoms. While valve is off remove plug to expose orfice on raise side so you can be sure it is installed and not loose. If not loose remove it to be sure it is clean and then blow some brake clean threw passages before reassembly with all new seals. Good luck

 

[Rig]

Thanks a bunch. Are you a tech_dealerIJ Would you consider letting me take off this valve segment and send it to you to check and fix. Auger swing and steering seem fine when header lift is struggling.

 

[NDDan]

Yes on tech_dealer. Email me if interested in sending. I'd have you send master section also just in case I don't find suspect problem in header valve. Going to be very busy until and when they finally get seeding so you'll have to allow me some time. Thanks