Combines Slippin 7720

HTR

Guest
Over heated hydro oil can cause the problem. Check the oil cooler to see if it is plugged. Weak relief valve could be problem. Change places with them and see if it helps. One is for forward and one for reverse. Worn belts and pulleys can cause the belts to slip. Some times hard to tell if they are slipping without somebody watching to see if they are slowing down when the problem occurs.
 

zbar

Guest
Could be a worn hydrostat. Install a gauge in the charge pressure test port. Should be around 250 PSI in neutral. Put the machine in 4th gear and lock the brakes and put some large blocks in front of the front tires. Run the machine WOT and watch the charge pressure gauge as the machine is stalled. The charge pressure should not fall more than 50 PSI from the reading in neutral. When the pressure falls more than 50 PSI it indicates internal leakage. Most likely worn valve and bearing plates inside the hydro unit.
 

Krzewina_Farms

Guest
we changed the hydro filter and oil....no difference. I noticed today that when the oil was cold, the combine seemed to have good power to the hydro. But soon after it warmed up, it started slipping. A new charge pump and hydro is $2400.. Does that sound reasonableIJ Thanks for everyones help!
 

HawkenCougar

Guest
Relief Valve!!, Relief Valve!!, Relief Valve!!, Swap forward and reverse to confirm. Very common.
 

Wheat_Reaper

Guest
If you have the manually locking hubs on your rear axle, they might be in the unlocked position. When they are in this position, the hydraulic oil bypasses the axle and it also messes up the drive to the main wheels or something like that. We leased a 9610 w_ this setup and whenever we hit a little mud, the combine would just stop with the stick all the way forward. Finally called the dealer to come out and look at it because we weren't getting anything cut, and he said all we had to do was to lock the hubs in. Fixed the problem, but remember to unlock them whenever you go down the road or else one of the wheels might lock up.