JD 4400 3pt drops like a rock

[chickenman22]

I'm working on my grandfather-in-laws JD 4400. The 3pt arms drop like a rock regardless of me having the control knob under the seat shut down. Doesn't seem to change speed whether turned towards turtle or rabbit. There is no draft control on this tiny tractor but i'm not sure where to start looking. Also the raise speed seems slow. loader works fine. Should I be looking at the rockshaft piston, control valve, or something else? Not sure how the internals work for the rockshaft control knob. Thanks!

 

[sisupower]

I'm working on my grandfather-in-laws JD 4400. The 3pt arms drop like a rock regardless of me having the control knob under the seat shut down. Doesn't seem to change speed whether turned towards turtle or rabbit. There is no draft control on this tiny tractor but i'm not sure where to start looking. Also the raise speed seems slow. loader works fine. Should I be looking at the rockshaft piston, control valve, or something else? Not sure how the internals work for the rockshaft control knob. Thanks!

Will it lift weight?

 

[chickenman22]

It will lift a tiller. the rockshaft control lever seems to only really work in the fully raised position and an inch down, any further and it completely drops. It was lugging the engine at fully raised but i found a rollpin that was missing on the adjustment rod that runs from 3pt arm to the rockshaft control valve.

 

[sisupower]

Sounds like its way out of adjustment. Try to find a manual for the adjustment procedures

 

[chickenman22]

Sounds like its way out of adjustment. Try to find a manual for the adjustment procedures

But wouldnt I still have speed control over the 3pt with the rate of drop valve? I would think that I should still be able to lock out the 3pt with the rate of drop valve regardless of adjustment, shouldn't I?

 

[RoyJackson]

But wouldnt I still have speed control over the 3pt with the rate of drop valve? I would think that I should still be able to lock out the 3pt with the rate of drop valve regardless of adjustment, shouldn't I?

You should be able to lock out the 3PH with the rate of drop knob. I'm thinking there's an internal leak or bypass (check valve?) stuck open.
I can't help much with the troubleshooting, but I do have a copy of the service manual. Drop me a PM with an e-mail address