Factory A/C Fan Speed Switch Source?
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From: Palm Bay, Florida
I was told that the BIG Ford L9000 type trucks/tractors use the same switch and these were made until into the 90s and should still be available that way, they are mounted horizontally in this series but will work in '73-'79 Fseries.
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From: Gadsden Purchase
After noticing all of the "big three auto makers" switches have trouble "on high"... I only use high when I really need it.
Also I fixed my switch. Took it apart and made a new contact for the "high position" and it's still going.
Alvin in AZ
Also I fixed my switch. Took it apart and made a new contact for the "high position" and it's still going.
Alvin in AZ
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That's weird because there is practically No Resistance when on the High position. Unless it is the amount of voltage going thru it and that heats the switch up to make it fail. The switch is before the resistor though.
I would expect more problems at low speed when there is maximum resistance.
I would expect more problems at low speed when there is maximum resistance.
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From: Gadsden Purchase
Originally Posted by Mil1ion
That's weird because there is practically No Resistance when on the High position. Unless it is the amount of voltage going thru it and that heats the switch up to make it fail. The switch is before the resistor though.
I would expect more problems at low speed when there is maximum resistance.
[Dennis]
I would expect more problems at low speed when there is maximum resistance.
[Dennis]
First gather the symtoms, then look for an explaination.
My guess...
Too high current on high to go for years like that -and- when the switch contacts get the least bit of resistance they become the highest resistance in the circuit so the problem snowballs.
BoltGunnner's switch "spit sparks" so his switch may be too far gone to fix.
I've re-worked the contacts in mine twice now that I' think about it. As soon as high started "acting up" I took the switch apart.I've thought about re-wiring the circuit so there's a very short piece of ni-chrome resistance wire in the high circuit (make changes to a replacement resistor-board and install it, plus run the high circuit through the new board somehow too) but I'll prob'ly never get around to it.
Alvin in AZ (both a tinkerer and a hammer mechnic)
ps- BG, 700VS 22-250
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Please note, that should have read "amperage" going through the switch not voltage.
My comments were more to do with Ford's circuitry.
I would rather have a relay to run the system.
Ford seems to like things to go through the switch for some reason.
My comments were more to do with Ford's circuitry.
I would rather have a relay to run the system.
Ford seems to like things to go through the switch for some reason.
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From: Gadsden Purchase
Originally Posted by Mil1ion
I would rather have a relay to run the system.
Ford seems to like things to go through the switch for some reason.
Ford seems to like things to go through the switch for some reason.
Reminds me of old air-cooled VW circuitry.
And yeah, like Jason said, a relay would be the way to go and maybe even increase the air flow over stock wiring too.
(instead of decreasing it slightly using "my" idea)Alvin in AZ (retired railroad "signal-ape")