John Deere 440c

Dylan B · August 15, 2024, 08:46:14 PM

I have a John Deere 440c skidder. Started acting up this week. When I first start, it operates norma. After a few minutes of rubbing the steering gets tight and hard to turn and I can barely get the blade to come off the ground. Changed hydraulic transmission filter and fluids are good. Any ideas?

beenthere · August 15, 2024, 10:15:55 PM

Dylan
Not a lot to go on, but welcome to the Forestry Forum.

Take it you didn't change the hydraulic fluid, just the filter? And what fluid do you use?

Maybe time to get a pressure gauge and start checking oil pressures to see if this is not a pump or internal leak.

Do you have the service tech manual?

Kodiakmac · August 17, 2024, 09:37:25 AM

G'day Dylan. Welcome aboard!

I had similar problems with my 440. They all went away when I installed a re-built hydraulic pump.

Satamax · August 19, 2024, 11:23:17 AM

The pumps have a reputation.

Daft idea. Instead of shedding 800/1200 dols in a new radial pump. Woulndn't it be easier to fit an electromagnetic clutch pump on the crankshaft ?

https://www.flowfitonline.com/products/flowfit-12-v-electro-magnetic-clutch-and-group-2-pump-assembly-4cc

B.C.C. Lapp · August 19, 2024, 11:34:14 AM

They do. Those pumps are buggers. But my money would be on the priority valve. (proper name might be the pressure control valve, I'm not sure) I kinda remember a long long time ago when I had a 44B I was having the same issue with my hydraulics. I started out to replace that valve and ended up just removing it and running without it.

mudfarmer · August 19, 2024, 04:02:49 PM

Same description of issue in this thread https://forestryforum.com/board/index.php?topic=104870.0 -- it was his priority valve. If it is like my A model you can just pull the "guts" out of the valve to test, you won't lose much fluid and it is a 15-30min job. If that's not it check suction tube and screen like they suggested in the other thread.