quadmethyl
New member
- Joined
- Oct 27, 2013
- Messages
- 4
I figured I would post this since I just fixed it and its fresh on my mind. I noticed that the normal whirring of my AirDog 2 DF-165 had stopped and so I checked the battery connections, fuse, relay, voltage, and continuity on the wires all the way back to the pump. Everything was fine but the pump still wouldn't kick on. Finally I wiggled the wires entering the pump body and the unit came alive. I removed the two bolts on the back of the pump body, where the wires enter, and removed the backside of the pump.
If you do this "BE CAREFUL"!!! There are two solid block brushes that are held in with mouse ear curled springs and if they are not coated in gunk will try to launch out when pulled off of the back of the motor. There is also an O-ring that seals the back of the pump cap that will need to be replaced on the cap when replacing it.
I expected to find a bad solder joint but what I found was that the block brushes had been so coated with gunk that they had stuck in their retainers and couldn't be held against the motor shaft by the mouse ear springs so eventually the gunk became a dielectric. I sprayed the components off with contact cleaner, waited until it dried, regreased the bearing on the back of the shaft, made sure the brushes articulated well, and replaced the motor cap with the O-ring. The truck fired up and the pump acted like it was brand new. I had never seen this problem mentioned in a forum so here you go.
As an addendum the two bolts that hold the motor cap on also hold the motor body to the gerotor housing. If you don't pull the motor body it will just stay up with the gerotor housing. I performed the entire maintenance without removing the entire pump unit but rather just the motor cap. I also recommend using a multimeter to troubleshoot the voltage all the way back to the pump unit itself.
I hope this helps someone.
If you do this "BE CAREFUL"!!! There are two solid block brushes that are held in with mouse ear curled springs and if they are not coated in gunk will try to launch out when pulled off of the back of the motor. There is also an O-ring that seals the back of the pump cap that will need to be replaced on the cap when replacing it.
I expected to find a bad solder joint but what I found was that the block brushes had been so coated with gunk that they had stuck in their retainers and couldn't be held against the motor shaft by the mouse ear springs so eventually the gunk became a dielectric. I sprayed the components off with contact cleaner, waited until it dried, regreased the bearing on the back of the shaft, made sure the brushes articulated well, and replaced the motor cap with the O-ring. The truck fired up and the pump acted like it was brand new. I had never seen this problem mentioned in a forum so here you go.
As an addendum the two bolts that hold the motor cap on also hold the motor body to the gerotor housing. If you don't pull the motor body it will just stay up with the gerotor housing. I performed the entire maintenance without removing the entire pump unit but rather just the motor cap. I also recommend using a multimeter to troubleshoot the voltage all the way back to the pump unit itself.
I hope this helps someone.