B3030 cab heat/defrost fan wont work below 32 degrees

[Michford]

The fan in the cab of my B3030 for the heat and defrost does not work when the outside temperature is below freezing. The fan worked fine last winter. I also notice the radio goes out when I turn on the heater fan which is odd as they should be on their own fuse. Anyone ever see anything like this? Is the fan located above the headliner? I looked on Messicks at the cab parts diagram and did not see where the fan is.

 

[BAP]

I would check the ground for the cab electrical system. There should be a ground wire running from the cab to the rest of the tractor. It is needed because most cabs have rubber bushings on the mounts. If the ground has become rusty underneath or the bolt is a little loose, then it will cause an intermittent problem.

 

[LouNY]

does it work again when it warms up?
If so sounds to me like it could have gotten moisture around it.

 

[number two]

Not sure,but I believe the headliner will need to be removed to remove the roof,giving access to the HVAC unit.
Others will know for sure.
Good Luck!

 

[fruitcakesa]

I would check the ground for the cab electrical system. There should be a ground wire running from the cab to the rest of the tractor. It is needed because most cabs have rubber bushings on the mounts. If the ground has become rusty underneath or the bolt is a little loose, then it will cause an intermittent problem.

This is the most common culprit with "weird" electrical issues

 

[BubbaJr]

Here's a link to the A/C - Heater motor assy. It is item #30. It looks like you will need to remove the roof to access the motor as it comes out from the top.

http://kpadweb.kubota.co.jp/kpad2/PartsInfo.do?bookCd=100K0845&funcCd=011&figNo=P10500&dispType=2

Good Luck,
Joe

BTW, I also think you may have a ground issue.

 

[Michford]

Thanks all for the suggestions. Temps got above freezing today, no fan. I will search for a ground wire for the cab to the tractor chassis, but there is not alot of room to search under the cab. Maybe I'll run a new ground wire if I cant locate the factory one. Dropping the headliner and pulling cab roof will be a spring or summer project to go deeper into the fan assembly.