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MGB 77 MGB Cooling Fan Problem

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kyreb1862

kyreb1862

Jedi Knight
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My 77 MGB has developed a cooling problem. The first radiator fan switch failed in the closed position causing the fans to run constantly. I then ordered a new fan switch and installed it. Now this switch doesn't seem to want to kick the fans on. The hook up and installation seemed to be pretty straight forward but the new swicth is not working. There is power up to the swich but, even after the engine reachs a temp which should cause the switch to operate,no power goes through it to the green/black wire going to the fans. I used a jumper and connected to the green/black wire and one of the fans kicked on. I think the other fan motor is bad. Does anyone know anything I can do to make the switch work? Or is this just something I'm going to have to return and wait for a new one?

Regards John
 
Hello John,

I would check the switch using a pan of water on the stove and monitor the temperature and see when or if it switches (using a meter or a battery and bulb). If it doesn't work at a sensible temperature I would send it back for a replacement.

Alec
 
John - do both of them not work?
 
Only the fan on the passenger side is not working. I can jump the switch and get the drivers side fan to work but not the passenger side.

Regards John
 
Yep, bad fan motor...you can take it to your local auto electric repair shop & they can rebuild it for you.
 
tony barnhill said:
Yep, bad fan motor...you can take it to your local auto electric repair shop & they can rebuild it for you. [/quote

Ok, that sounds like a plan. I'll pull the fan motor today and take mit into the repair shop tomorrow.
Click to expand...
 
Whenever I disassemble a car, I check the fans to make sure they work by putting 12V directly to them....if one doesn't, I take it to my local guy who rebuilds it before I put it on my shelf.
 
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