Just for folks reference, at about 2000 hours my heater fan gave out. Pulled the cab roof off and popped the fan out. Brushes worn out and the copper leads ran against the commutator down to the ceramic in the middle.
I thought it might be 100$ for the motor, nope, 700$ at our dealer. Try crossing the motor at NAPA, electric motor shop etc no luck, found one online at a motor shop in england. Surplus Centre has one that is almost right but couldn't be sure the shaft was right for blower wheel for 10$ but its a pain buying from the US here. Its a 0.266" shaft (I think that it was 7mm or something )close) 60 mm diameter motor.
Motor is made by Denso of Japan that supply oem motors and heaters to RV manufacturers etc and seem to supply Kubota as well. They don't sell parts though.
So chucked the armature into the lathe and turned down the commutator to flatten it out some and cleaned the gaps out. Couldn't clean it all the way or it would knock the segments off. Went to starter / alt shop and was given some old dodge brushes of similar hardness for free then filed them down to fit the brush holders. Soldered the new brushes in with old heavier copper braid leads in parallel with vice grips pinched on to stop solder from sucking up the braid.
Reassembled with a drop of oil in the bushings and the blower runs like new! 700$ saved for about 1 hour actual work.
