Rear Defrost Questions

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Joined
Jul 24, 2018
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Location
Northville, MI
My Car
70 Maverick Grabber w/351W & Toploader
71 Mach 1 w/ 429 & T56
Hi guys -

I'm in the process of installing my rear defrost glass into my 71 and had a few questions. I currently have two pieces, both have minor scratches, both I believe work, but looking for some help from anyone who may have more expertise:

1) The attached pics show what I have. Does this look correct, and am I missing anything (I believe I am)?
2) Does anyone have a pic of how the sail panels interact with the glass (where the wires come out, how the wire covers attach, etc)?
3) Does anyone know of a good procedure for testing one of these pieces before install?
4) Does anyone know if scratches will cause an issue when operating (more prone for shatter)?

Thanks,

Marc
 

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1 - missing a bunch of parts, see the wiring diagram below.
2 - dig around on the 429 Megasite, IIRC there are some pics somewhere in there http://429mustangcougarinfo.50megs.com
3 - I'd mount the whole setup on a piece of plywood and power it with a battery beforehand
4 - ¯\_(ツ)_/¯



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Marc, if you are adding rear defrost to a car that didn't have it, you are missing a number of things.
Ground wire that connects to the passenger side of the glass
Behind the dash wiring and relay
Defrost "on" indicator light
Wire harness from the starter solenoid over to behind the driver kick panel
Wire lead covers where the leads connect to the window
The switch you have has the toggle broken off (common problem, but repairable via rebuilding using a repro convertible top switch)
Metal washer piece that goes between the switch and the back side of the dash
Chrome nut that holds the switch, metal washer and bezel all together to the dash.
The wire you have is the 73 type (green connector) as appears to be the glass. 71/72s had wire leads soldered to the window
73s were higher wattage than 71/72s and used different wire connectors and thicker gage wire
73s used a fusible link at the starter solenoid, 71/72 used a circuit breaker
Alternators were generally higher amperage than cars without defrost to handle the increased power draw when the defrost was "on"
 
Yep, you're missing a lot of parts, as has been said. As for the scratches, there isn't enough heat in it to cause glass to shatter. If some of the "filaments" across the glass are scratched, there used to be a liquid you could patch them with.

2010_02070003a.jpgInterior a.jpg
 
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