Headlight "Doors"

Back in my first post I stated:
"One of the existing (original) doors had a bit of damage to the aluminum casting along one edge. It's a small dent or crease upward (away from the car) that caused a tiny crack in the cast metal."

As I removed the finish from the doors I discovered the other door also has a hairline crack in exactly the same location as the first. However this door has no damage to it (it's not bent like the other one). I wonder if there was some sort of manufacturing issue with these doors that lead to the cracks? I'm still not certain how the first door became bent upward in the particular location. But the fact both have similar cracks in that spot is curious. The crack in the first door is larger but it was not obvious until I started looking closer at the bend. And it turned out to be bigger than I thought once everything was stripped. The crack in the second door was not visible at all until the finish was removed. So who knows how many other X's have cracked headlight doors but it doesn't show.

Perhaps one explanation for the cracks (and possibly the bend) is stress from the motor driving only on one side of the door? As the pivot bushings become dry and corroded they get stiff (we've seen some bushings that actually broke apart). That may put force cross the top of the door in between the two bushings as the motor torques it. And that is where the cracks are located.
 
Thanks, that sounds like what I'd expect, a rather standard process. Given the propensity for these to sluff off the finish I thought maybe there was some sort of special prep treatment like exists for some other substrates.

Check out Aircraft Spruce. They have a number of products for paint prepping aluminum, including restoring, or paint preperation. They are toxic and costly, and I have had good results. I have not given them the test of time and weather: I do trust products made for the aircraft industry.


 
to anybody out there,
I have an electrical issue with the pods not closing after a body repair.
they open ok but do not close. I checked the master Lighting switch, relay, fuse-box etc. I put battery power to the green/white wire at the motor and it opens and closes, so it can't be the diodes. any thoughts?
 
Thanks Rudy, I haven't heard of that product - I'll look into it.
it,s used all over the ABE Aviation industry. its, basically the same stuff BOEING is using before their max 8,s are painted. thats why they look greenish/yellowish befor the customers painting.
 
Tony, I've decided I'll blast mine as well. The top surface is pretty flat and can be sanded easily. But the rest of it has too many contours, cast brace structures, pockets, etc, to sand. And I'm finding the corrosion is over the entire surface of the whole unit. The more I remove the existing paint the more I see there is oxidation under it. So this is definitely a issue with improper prep before the factory finished them. Like pretty much everything on these cars, the headlight doors are turning into a bigger project than I imagined. :(
Sand blasting is the way to go , 5 minutes per light and not dealing with any chemicals,
 
Back
Top