[Duane4238]

The boss just brought home a JD 2940 4wd with cab from the farm auction. The tractor has a heater/ac unit overhead in the cab, but nothing works. After a quick look, I noticed the heater hose coming off a shutoff valve near the radiator has been cut off and it's connected onto another hose to keep the system closed. Maybe there was a leak in the overhead unit and the PO just unhooked it. The fan also does not come on when switched so there may be some electrical issues to deal with too. Before I get into it, I was wondering if it's easier to take the whole unit out to work on it, or should I leave it in place and work on it overhead?
Duane

 

[jd110]

Is this a factory sound gard body or and aftermarket cab? The factory unit really had no way of removing the entire a/c heater unit as an assembly, so I am wondering if it is a add-on system? I would connect the heater hoses and pressure test the system to see if the heater core is leaking. Then start tracking down why there is no blower motor function. Maybe a fuse or circuit breaker. Some pictures might help identify what you have.

 

[blackfoot1]

Duane4238,
If the cab looks like the image below, it's a factory built Sound Guard Body.
Otherwise, it's after-market.
As jd110 stated, the a/c unit is not removable as a unit.

 

[Tx Jim]

If tractor has a factory SGB(cab) a good place to start looking for an electrical problem is the printed circuit board(parts key #4). The dash cover snaps off so printed circuit board can be accessed. I'll warn you that the wiring diagram on a 2940 with factory cab resembles a "spider web".

 

[Green Weenie]

Is the roof of the cab removable? You might be able to get some work done up there from overhead.

 

[Tx Jim]

Is the roof of the cab removable? You might be able to get some work done up there from overhead.

Yes the roof is removable. Remove 3 screws under the front on the curved part and 2 bolts from the top.

 

[Duane4238]

Good news is the cab is an aftermarket model and the heater unit actually unhooks and swings down for repairs. We found a bad connection in one of the wires, repaired it, and the unit now works. The bad news is the heater core has been disconnected from the heater hoses, and the hoses have been removed. I'll have to remedy that. Also, the boss was told at the auction that the heat and AC had been disconnected, but actually, there is no AC, Just a big blower. Thanks for all the help and suggestions. This forum is invaluable!
Duane