Heater Blower Fire

[zoom240]

Well, it's not quite an emergency, but I could use some advice. About four months ago, I was pulling out of a parking garage & smelled smoke. I got the fire out, drove it home & was so disgusted I parked the Z for 4 months while I worked on other projects.

Today I finally crawled under the dash & found what happened. I think the heater switch failed & started a fire. I'm not sure why, but a couple of suspicions:

> could have just been 25 yrs of crud & dirt

> I've been running over-voltage because I haven't been able to track down why the voltage-regulator can't maintain voltage. Have replaced it twice. Might need to change out the alternator.

So questions:

I did some checking & you can't just replace the unit. You can see the fan blade is melted & will wobble from now on. Any source on parts for it? I'd like to replace the melted duct, but a junk yard is the only likely source. I've not had much luck here (New Orleans area). What about the heater switch - I guess I can just replace the switch. Anything I need to know that could cause problems there?

The over-voltage problem. Do you think that was the root cause? Runs about 16 volts normally. I'm looking at changing out the alternator next, I think.

Finally, I've done searches on this forum in the past to look for replacement wiring harnesses, but I've never found a source (other than the generic harnesses). Anything changed?

Thanks all,

Dave

Car: 1978 260Z 5 speed with air (yes '78 - brought it from Holland & they sold the 260 there while the 280 was being sold in the US).

[Ed]

16 volts? Seems a little high. Isn't 14 about average?

When you melted the unit was it running for a while?

[zoom240]

I'd been having trouble with the voltage for several months, so it's not like it was a new problem. I'd changed out the voltage regulator twice & was thinking about changing the alternator. 16 volts is high - it used to be very steady at just over 12.

The car had been running maybe 5 minutes when the heater caught on fire - just enough to get from the top of the parking garage to the bottom.

Dave

[wal280z]

I did some checking & you can't just replace the unit. You can see the fan blade is melted & will wobble from now on. Any source on parts for it? I'd like to replace the melted duct, but a junk yard is the only likely source. I've not had much luck here (New Orleans area). What about the heater switch - I guess I can just replace the switch. Anything I need to know that could cause problems there?

Dave-

I've got a blower unit complete w/o the flex. duct (just sold that recently), however, this one is for units w/o A/C. The dropping resistors (the wire wounds inside the heater blower case you see in your pic) are wired to your switch, however, I tend to believe that some crud was in there that when it got hot (from the heat dissipation of the resistor switch), it started a fire. Do you recall what fan setting you had it on? "HI" is basically a straight short, where the other speeds use the resistance. Send me a PM if you are interested. The unit that I don't need is on the right. I also have the fan switch for 3 speeds if you are interested in that.

Wayne

[zoom240]

Wayne,

Thanks, but I'm going to look around a bit & see if I can find one for the air, but I'll keep it in mind. I will have to replace the blower motor - it had been making some noise :stupid: , when I pulled it apart - the armature is very worn. Probably was arcing. Not sure the picture really does it justice.

Dave