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Discussion Starter #1
What is the simplest procedure for replacing the heater fan motor? It looks like the whole dash has to come out to get clearance enough to pull out the bottom of the box where the motor is. Please tell me there is an easier way ('79 Spider). ThankS!
 

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Hmm... Interesting, that's what I would like to know aswell. I always thought takeing the center console out would do, but I remember that sucker being deep in there.

By the way, what's wrong with you're heater? Did the fan blow or is it leaking?
 

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The fan is at the bottom half of the heater box. The fan can be removed with the dash still in. The heaterbox has four metal clips that hold the lower box in. Two in the front (easy) two in the rear between heaterbox and the fire wall (tougher). I flick the clips open with a flat blade screwdriver. You sould then be able to slide the lower heaterbox out. This has the fan in it. Of course you first have two remove the center consel and the heater ducting ect. I just remove my heater last weak. To get the upper part of the box that has the lines and radiator in it, it is easier to remove the dash but if you only needed to get to the fan leave the dash in. Dealing with the Wiring and speedo and tach cables is harder then the heaterbox.
 

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Discussion Starter #4
Well that sounds fairly easy - I guess i need to look for those clips. My fan is frozen from rusted bearings. I can reach my hand inside the box and when I try to spin the fan, its very tough to move, like the bearings are filled with rocks. I made the mistake of turning on the fan switch, and wondering why nothing was happening, only to smell smoke from the fan wire heating up and melting the insulation. Now Ive got to replace the wire and motor. The motor was never used by the prior owner I guess, but I drive the car on cool fall nights so I really want to get the heater working again.
 

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After looking at the heater box agin today it looks like there may be a third clip on the backside. Mine only had four but one may have been letf off an earlier repair. I hope I haven't messed you up.
 

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This is a timely post! I've been edging up towards this repair for a while now...console is out, right duct is off, two aft clips are off, so I guess I need to pop off the front clips and pull the left duct, and I can se what I've got. I can spin the fan by hand, but it's hitting something. Sounds like there was either something dropped into the fan via a duct, or the fan has shifted on it's shaft and is hitting the housing. My car is a '78 Spider- can anyone tell me definitively which wires go to which terminals on the fan switch? The fuse was blowing immediately, so I think there was a dead short at the switch, but I can't deduce the correct wire positions, and my wiring diagram doesn't get that detailed. Thanks in advance! Pat Hood, Pair O' '78 Spiders,
NWARC, Seattle.
 

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Hey CarPoor,

I think I can help you out with your switch wiring. I've been struggling with that **** thing for a week and I've finally got it working (I think*). I had an internal fault with the switch. Don't take that thing apart unless you've got 5 pairs of very small hands to get it back together.

My car is a 78 UK Spider.

I don't have terminal numbers available, but hopefully this description will be good enough:

Rip the switch out of the console. As you look at it, there's three spade connectors on the top and two on the bottom. Top left and bottom left are actually the same piece of metal (i.e. always connected to each other)

Top left is not connected.
Bottom left has a yellow wire**
Bottow right has yellow wire with black stripe**

yellow and yellow with stripe go to the fan motor. One of these also has a second wire which operates the warning lamp on the dash**.

You then have with the two connectors on top right. The one with black wires (Earth) should be covering / on top of the one with red wires (12v)

Internally:

Switch off : Earth is connected to top left and bottom left (Shorts out motor, has braking effect when turning off motor)
Switch in middle: 12v is connected to both bottom terminals and top left (power to both +ve brushes in motor, i.e. full speed)
switch to bottom: 12v is connected to bottom left/top left only** (power to one +ve brush only, half speed)

Hope that helps!

I can get you exact details if you need. You sure the fuse isn't blowing because the motor is stalled ?? (stalled motor = high current)

Dan.

* I say I think it works, but I'm getting full speed in mid position and slow speed with the switch in second position. Having dismantled the switch and figured out how that complicated **** thing works, I think that's the way it is supposed to happen!

** from memory! I may have got the exact details of the bottom two terminals (Yellow wires) mixed up, but you should be able to get the gist of how it works from the above.
 

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Thanks, Dan (BeigeAlfa)

Dan- Thanks very much. I'll have a go at this after I get a new fan or rebuild this one. I took the fan out last night, and it looks/sounds like the fan has slipped down and is hitting the motor itself. Also, there are NO brushes left at all, and there's corrosion in the armature. No way that thing would have ever run... I think the switch may be bad also, because we checked it with a VOM, and couldn't get any logical readings. I appreciate you taking the time to post that detailed description. I'm printing it out for future reference once I get the fan functional, and I'll let you know what I find. Boy, getting the heater out is certainly a fun job!
 

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Dan - the fan in my GT Junior seems to be switched that way i.e. full speed in the first position and slow speed in the second position. I guessed that it was wired the wrong way round - maybe not then.....
 

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Alfa wired the fan switches backwards for UK cars. Afterall, you guys drive on the wrong side of the road.

(just kidding, I couldn't resist)
 

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Replacing Heater Fan

Ironman,
Just wondering how your heater replacement effort went and if you have any advise. My center consoul is out and my dash is loose except for tac and speedo connections. I just started a complete interior restoration of my '78 Spider. My heater fan problem sounds identical to the one you had. Also wondering if you rebuilt or found a replacement fan motor. If replacement where did you shop.

DSpeer
 

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Discussion Starter #12
Well, truth is I haven't tried to replace it yet. You may have seen my other threads regarding my cylinder head problems. I haven't done anything else, and won't start a new project until that's done. As for the fan, I bought a used one from Ebay. i think it was 40 bucks.
 

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Guys- Int'l Auto Parts has the fan new. About $80 or so...he one I got had a fan that looked right, but was too large and wouldn't fit into the housing, so I had to use the old fan. HTH.
 
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