rear heater questions/sollutions (1 Viewer)

Joined
Sep 18, 2022
Messages
39
Location
vernon bc canada
hi all, ive been happily working on my new to me 78-fj40. with winter on its way i want to be ready with as much heat as possible as this will be my daily. i noticed the rear heater doesnt work, i checked the conection under the console. its plugged in, i assume that conection is the power and the unit itself is grounded as theres only one wire on the conection, i assume the motor is dead. what motor/fan can replace the motor or are they repairable in any way. thanx for any tips.
 
Joined
Apr 2, 2008
Messages
11,389
Location
Victoria, BC
There can be rewound if needed. It’s most likely corrosion in the bushings or that it needs brushes. I’d recommend opening it up and see what’s going on.
 
Joined
Apr 2, 2008
Messages
11,389
Location
Victoria, BC
There should be power to the rear heater when the fan is on high speed on a single speed rear heater.
 
Joined
Oct 30, 2011
Messages
685
Location
Lakewood, WA
Just replaced my rear heater hoses over the weekend. The single wire is the only power to the motor. I wired mine to a dedicated switch so it can be run independently from the front fan. I'd try powering it up from a different source to see if the motor will spin. If not I've also heard about someone was able to get the motor to work again using a drill to rotate the fan shaft for a while to clean up the inner contacts. Good luck!
 
Joined
Sep 18, 2022
Messages
39
Location
vernon bc canada
got lucky....i took it apart and took the motor out and tried it with power and a ground and it worked,,,,put it back in and it didnt work, checked the power and had only 10.5v on that wire with fan on high. i removed the ground wire and ran it to the chassis and then it worked fine with the fan switch. not sure why the factory ground was bad but glad it came to life, and the heat valve to direct antifreeze worked perfect too whooohooo.
 
Joined
Apr 21, 2005
Messages
22,081
Grounds are a big issue on these old FJ40s. Not sure what dedicated ground your rear heater had. Mine always grounded thru the mounting bolts to the floor. Checking for voltage and the ground are what I always do first. Tearing into a motor would be the last thing I would do. Never seen dielectric grease mentioned on mud. Clean the threads and area ground is needed then use some dielectric grease would help keep a ground from getting corroded.
 

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