Fixing a 79/80 Front bumper strip
#1
Senior Member
Thread Starter
Fixing a 79/80 Front bumper strip
Like many of you I discovered a major flaw in Mazda's design of the front bumper. When I removed the rubber bump strip I found that the backing plate which attaches the rubber to the car had corroded to little more than dust.
Replacements from Mazda are available for the ripe sum of about $130. Being a frugal Yankee (ok cheap) by birth I figured I'd give replacing the backing a try before shelling out the bucks. What came out is actually, IMNSHO, an great improvement on the original design.
Here's how you do it"
Get a strip of 1/8" x 1 1/2" x 36" of Aluminum at your local Ace Hardware store. I frequent mine. They know me by name. Thirty six inches is actually about 1 1/2" short of ideal but still works. The strip fits almost perfectly inside the rubber.
To make the studs I drilled holes on the ends of the aluminum in line with outer most fixing holes in the bumper and inserted Rivnuts. (A rivnut is a threaded sleeve that installs into a hole using a tool like a pop rivet gun.) After filing down the long end of the rivnut a bit I inserted 1" Phillips head bolts in the rivnuts and snugged them down with some Locktite for good measure. After these were set I filed off most of the screw head so that there wouldn't be a visible bump in the rubber.
You will need to enlarge the holes in the bumper to allow for the rivnut to stick inside the bumper, Use two or 3 washers to take up the remaining ength of each rivnut inside the bumper before installing the nylocs. Notice that I only used two bolts, one at each end. That's all that's needed because the aluminum is stiffer and holds the shape of the bumper better.
I used stainless hardware to prevent galvanic corrosion with the aluminum. Cost is about $16. Pictures are attached. Feel free to ask questions.
Replacements from Mazda are available for the ripe sum of about $130. Being a frugal Yankee (ok cheap) by birth I figured I'd give replacing the backing a try before shelling out the bucks. What came out is actually, IMNSHO, an great improvement on the original design.
Here's how you do it"
Get a strip of 1/8" x 1 1/2" x 36" of Aluminum at your local Ace Hardware store. I frequent mine. They know me by name. Thirty six inches is actually about 1 1/2" short of ideal but still works. The strip fits almost perfectly inside the rubber.
To make the studs I drilled holes on the ends of the aluminum in line with outer most fixing holes in the bumper and inserted Rivnuts. (A rivnut is a threaded sleeve that installs into a hole using a tool like a pop rivet gun.) After filing down the long end of the rivnut a bit I inserted 1" Phillips head bolts in the rivnuts and snugged them down with some Locktite for good measure. After these were set I filed off most of the screw head so that there wouldn't be a visible bump in the rubber.
You will need to enlarge the holes in the bumper to allow for the rivnut to stick inside the bumper, Use two or 3 washers to take up the remaining ength of each rivnut inside the bumper before installing the nylocs. Notice that I only used two bolts, one at each end. That's all that's needed because the aluminum is stiffer and holds the shape of the bumper better.
I used stainless hardware to prevent galvanic corrosion with the aluminum. Cost is about $16. Pictures are attached. Feel free to ask questions.
#2
Moderator
iTrader: (3)
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,829
Received 2,597 Likes
on
1,845 Posts
lmao, that is way better than the Mazda design
Thread
Thread Starter
Forum
Replies
Last Post
jreynish
Suspension/Wheels/Tires/Brakes
3
03-28-16 10:47 AM
nissan-300zx
1st Generation Specific (1979-1985)
8
06-25-06 07:56 PM