Georgia Fiero Club Forum

All Things Fiero => Tech Tips, Tech Questions => Topic started by: Fierofool on October 28, 2018, 11:14:15 pm

Title: Preventing Fires--Climate Control Cleanout
Post by: Fierofool on October 28, 2018, 11:14:15 pm
Over time there has been lots said about keeping the climate control system clean of debris.  Pennocks is full of information but very little has been posted on this forum.  I just want to open the eyes of some who may not be aware of the fire hazard that can be lurking in your heater box, especially newer Fiero owners.

The problem might be more common in a car that's seldom driven.  Mice or Chipmunks will frequent the car more often, even making living and birthing quarters in it.  If you are seeing debris in your dash vents, it's time to take action without delay, but don't wait until you do see debris. 

There is a ballast resistor accessible in the front compartment.  On AC equipped vehicles, it's just to the passenger side and toward the bottom of the silver canister or accumulator.  It will have a harness with several wires going to it and 2 screws that hold it in place.  This is the true danger area.  There are 3 coils on the back of the plate.  These 3 coils are resistors for the 3 lower speeds of your heater and AC blower motor.  When either of the 3 lower speeds are activated, the corresponding coil glows red hot, just like a coil on a hot plate. 

Little critters can climb up through the larger rubber cowl drain tubes that are visible on either side of the front firewall.  Once up inside the cowl, they can gain access to the inside of the heater box.  Leaves and other debris can work its way into the cowl area around the opening between the bottom of the windshield and cowl cover, around the front decklid latch, and several areas along the lower edge of the cowl cover.  If you succeed in keeping it out of these areas, critters will bring their own.  They will steal insulation from inside the vehicle.  Climbing through the footwell vents and getting padding from behind the carpet, seats, or anywhere in the interior. 

The best way to clean out the system is to remove the heater box cover underneath the passenger side dash, remove the ballast resistor and remove the heater motor and its attached fan.  For some reason, the critters love to build their nests around the resistors.  Debris pulled in through the upper cowl has to pass by these resistors and it often doesn't get by and lodges in or against the resistors.  Should any of this debris catch fire, it's near impossible to extinguish because it's in an enclosed area.

During the RFTH 23 Rerun, being a cold day and a rainy day, both the heater and defroster were in regular use on my 86SE.  It worked well with no indications of any problems or any burning smells coming through the vents.  I can say that I got a warning on my 87 when I smelled leaves burning.  When I removed the ballast, I found leaves caught in it and they had already shown signs that they had smoldered.  Back to the 86, though. 

At some point late in the rerun, my blower motor started to make some horrible screeching noises.  I didn't take long for me to realize that the motor bearings had failed, so today after Church, I pulled out my spare and set about to replace the old one.  Now, I've been driving this car on a fairly regular basis, but in the early years, it sat for a couple of years until I got a motor for it, and prior to that, it sat in the previous owner's garage for an unknown lenfth of time.

It didn't really surprise me to find debris when I removed the motor and blower, but when I felt over toward the resistor, I was horrified.  I could feel nothing but debris.  I have no idea how my climate control system worked at all.  When I removed the resistor, debris was all around it.  Some of it had actually melted to the coils, making a bridge between coils. 

Below is what I got out of the area.  My 10 1/2 foot is there to give you some perspective of the size.  The horizontal view is about 5 inches high.  Lots of hair, some automotive insulation, leaves, bits and pieces of seeds and acorns and pine needles.  I have no idea where the hair came from unless it came from the previous owner's period of ownership. 





A thread from Pennocks.   http://www.fiero.nl/forum/Forum2/HTML/141959.html
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: PK on October 29, 2018, 08:01:22 am
I have done this before but a timely reminder to do it again.

The critter talk also made me realise that although Dangermouse is now in nice fresh air, I need to shut the doors and boot (currently open) to deter ready critter access!!

Thanks
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: Fierofool on October 29, 2018, 08:33:21 am
Even with everything closed, they can still climb up through the cowl drain tubes.  My cars stay outside, so they are more exposed to critters than if inside, but if a critter can get to it, it can get into it.  Those cowl drain tubes are about 1.5 inches in diameter and extend down to the area of the steering rack. 
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: PK on October 29, 2018, 09:31:46 am
When I did this before, I only did the clearing around the ballast resistor accessed from the bonnet.

I will have a go at the cab side too this time.  Is this a reasonably quick job?  Either way it's added to my long and growing list of Fiero tinkerings.
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: Fierofool on October 29, 2018, 11:01:17 am
It takes about an hour to an hour and a half.  Because my heater core had been replaced during the summer, I didn't remove the cover on the inside.  All of this is what came from the front area, packed up against the AC exchanger coils.  I suggest you remove the fan motor and the resistor.  As was suggested in the Pennocks thread, be careful not to damage the fins on the condenser.  I used a piece of rubber hose inserted into the vacuum hose end and inserted it through the opening for the fan motor.  It would grab a chunk and I'd have to pull it out and remove it from the end.  Material was too far back inside to reach with my fingers. 
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: Raydar on October 29, 2018, 11:36:33 am
Wow! That's one thing I need to do on the Ghost. Haven't done it yet.
Since it's a Arizona car, and was quite clean, I haven't thought much about it. Perhaps I should.
Thanks!
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: Fierofool on October 29, 2018, 01:34:19 pm
It should probably become a yearly maintenance item.  "Remember....Only You Can Prevent Fiero Fires."
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: pgackerman on October 29, 2018, 07:06:08 pm

Whoa... big foot.

Title: Re: Preventing Fires--Climate Control Cleanout
Post by: TopNotch on October 30, 2018, 10:17:56 am
Do you wear those fancy wingtips when you're working on cars?
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: Fierofool on October 30, 2018, 11:02:09 am
Sometimes.  I had just come home from Church and didn't change.  As long as I'm going to be on my feet, I don't usually change.  If I''m going to be down on the ground where the shoes can get scuffed and scraped, I will change. 
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: PK on October 30, 2018, 12:10:15 pm
I would destroy those shoes within seconds regardless of what I was doing!

Always wondered what wing tips are.. Now I know.
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: GTRS Fiero on October 30, 2018, 04:12:15 pm
They look like shoes.  What makes a "wing-tip" different?
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: Fierofool on October 30, 2018, 05:26:18 pm
The perforated design toe.  Some styles just have the decorated toe.  Others have more decorations like mine that extend to the heel, and around the opening of the shoe. 
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: GTRS Fiero on October 30, 2018, 05:32:52 pm
Breathable shoes.
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: Fierofool on October 30, 2018, 07:18:36 pm
It's actually a second layer.  The holes don't go all the way through.  At least on none of the pairs I've had.  Might be a good thing.  Instead of Big Foot, when I was a kid my sister called me Stinky Toe. 
Title: Re: Preventing Fires--Climate Control Cleanout
Post by: GTRS Fiero on October 30, 2018, 09:12:45 pm
LOL!