My blower has burnt up a couple relays over the years to the point that the relay sockets are shot. We wired it direct into fuse box w/ inline fuse and it is ruining that. Quit the other day and inline fuse holder was burnt and 15A fuse was blown? Blower sounds fine, Seems like it is over drawing. How many amps should it pull on high? Has anybody else had these same problems? I am thinking of just replacing blower. Seems like a pain do to being mounted in the ceiling panel of cab
Poor grounding can cause heating in the power feed especially at the connections. Check the web ground straps to the cab and frame located on the right of the trans. Run a temporary ground straight from the battery to the blower and see if it happens again. There is a resistor near the blower motor that is for the different fan speeds. Be sure it also is grounded well or maybe it is bad.
Most faults I have seen with these blower motors is that the brushes are worn out. If you're handy with electrics they can be pulled apart, cleaned, new brushes can be purchased from an auto electrical wholesaler, solder them in & you can test them on the bench before installation. ....... or you just buy a new motor & grin & bear the cost. Getting the motor out of the roof is the hardest part of the job - without damaging any of the dozens of plastic panels & clips .....
I figured it was going to be a pain to replace. When I do it I will just replace. I dont want to back in there any sooner than I have to
I Grinned and eared it and bought the blower from the dealer. Any tips on installation? Especially on the removal and reinstallation of the roof panel. Luckily I have a heated will lit shop to work in
Also wondering if I should replace the resistor while I have it apart? New fan does not include it.
Probably be a good idea to replace the resistor while your in there, that way you can pretty much rule it out if you have more issues. What did the blower cost? Mine won't run on high. I'll be needing to take the headliner down soon to investigate why. Let us know how it goes.
Cost at dealer for blower was $270 plus tax. Resistor was $70 plus tax. Blower instock resistor will be here wednesday. I know from auto experience that if you loose a speed on your fan it is usually the blower resistor.
I am sure the setup is the same as autos. Full voltage provides full speed of fan. Each of the lower speeds is created by reducing the voltage at the motor using a resistor. if you have high speed only then it is the resistor. if you have no speed but other speeds than you have an issue with high blower circuit. Many vehicles use a relay for high speed. if the resistor is failed is is almost always the thermal limiter that goes bad in the resistor due to over current. In other words your motor is bad and caused the resistor to fail.
Good to know. I am burning fuses and relays. Motor sounds fine but something is over drawing so I am changing both
So I replaced blower and resistor yesterday. It was not to bad of a job. Took about 2hrs? Nothing that was a major struggle. I did not see anything physically wrong with motor. I can see if your machine had AC it would be a tougher job I would think. I was able to remove the 4 nuts that holds air box to roof and let it hinge down and rest on steering wheel and not have to remove heater hoses. then motor just slides out. There is a main harness plug out side of air box so wiring can be unplugged prior to dropping box to make it easier. 5 screws hold head liner up and 4 nuts hold air box to roof.
Good to know. Thanks for posting! I have the same machine, no A/C, and need to pull mine down soon. My high speed is not working, need new cab filters. The headliner looks like crap so I'll need to do something with that while it's out. Have to work outside so hopefully get a couple warmer days soon.
It wasn't that bad at all. you have to remove knobs from controls and pull the bezel so you can pull the pillar cover loose and let it lean out. Head liner tang goes in behind it. Then flexing the head liner to get it around the coat hook ect. I had to flex it a fair amount to get it out and in bad not overly difficult. It did help that I had a 60 degree well lit shop to work in also
Thanks for the tips. Getting a few warmer days in the forecast soon. Hoping I can get in there and have a look!