View Full Version : Bumper guard bolts
ALLZS
06-01-2021, 07:30 PM
What are the correct style & markings for the bolts that go to the rear bumper guards on a 69 z/28 camaro
jl8z28
06-01-2021, 09:56 PM
What are the correct style & markings for the bolts that go to the rear bumper guards on a 69 z/28 camaro guard bolt
ALLZS
06-04-2021, 12:51 PM
Thanks
rlw68
06-05-2021, 05:06 PM
The lower bumper guard screws are GM 9780422, dark phosphate, 5/16-18x3/4. It's the same one that's on the license plate bracket up front. I'm not sure if specific manufacturers are expected, or if there are any formal judging guidelines.
:smirk:
ALLZS
06-05-2021, 07:05 PM
anyone have a good photo of the lower bolt
rlw68
06-06-2021, 04:15 AM
This
195747
Or E, or RBW, or one of each apparently
https://www.yenko.net/forum/showpost.php?p=1330685&postcount=3
195748
olredalert
06-06-2021, 02:48 PM
----I believe the bolt in the no.1 post is an rsc which is a known GM supplier bolt.....Bill S
m22mike
06-06-2021, 03:25 PM
Lower rear bumper bolts are bright plated zinc or cad .
https://www.yenko.net/ubbthreads/pics/usergals/2016/11/full-2974-53035-dscf6035.jpg
ALLZS
06-06-2021, 06:44 PM
here is whats on the car upper are black phost plated lower are silver zinc plated
mhm1966
06-09-2021, 05:45 PM
I just took my rear bumper guards apart. It looks like the "RSC" bolt that holds the bracket with the N with a circle around the N was zinc plated not black phosphate. Can I get some other input before I plate my bolts.
Edgemontvillage
06-10-2021, 01:27 AM
Mike, from original cars I've seen the lower rear bumperette bolts were clear zinc (silver) plated. They are often misread as phosphated because the original plating has been sacrificed over time. Here is a photo of a 22K mile 9C built Norwood survivor.
https://live.staticflickr.com/65535/51238102665_f86c8ee4de_c.jpg
mhm1966
06-10-2021, 12:23 PM
Lloyd,
I agree with the bolt in your picture should be clear zinc plated. I was talking about the other bolt "RSC" head mark that looks like black phosphate. My bolt that hold the bracket to the bumper guard shows no evidence of being black phosphate plated.
Edgemontvillage
06-10-2021, 02:26 PM
Mike, from original (and NOS) examples I've seen the bumper hook is silver cad and the bolt is either cad or zinc.
https://live.staticflickr.com/65535/51238269318_42c155ceaa_c.jpg
https://live.staticflickr.com/65535/51239121745_7bd08f7a57_o.jpg
rlw68
06-10-2021, 04:56 PM
Mike, from original cars I've seen the lower rear bumperette bolts were clear zinc (silver) plated. They are often misread as phosphated because the original plating has been sacrificed over time. Here is a photo of a 22K mile 9C built Norwood survivor.
Lloyd, the lower bolt is p/n 9780422 according to the AIM (also found on the front license plate) However this has a screw-like point on the end and no capture washer. Its definitely not the same as you are finding on the survivor cars. On your CRG thread from a few years ago one person replied that "my Norwood 12D 69 Z is originally blacked out on the bottom extension pieces of the rear bumper guards, and the bolts are black phosphate."
Perhaps it could be yet another change made sometime during the production year?
http://www.camaros.org/forum/index.php?topic=15233.0
:dunno:
Edgemontvillage
06-10-2021, 06:46 PM
Lloyd, the lower bolt is p/n 9780422 according to the AIM (also found on the front license plate) However this has a screw-like point on the end and no capture washer. Its definitely not the same as you are finding on the survivor cars. On your CRG thread from a few years ago one person replied that "my Norwood 12D 69 Z is originally blacked out on the bottom extension pieces of the rear bumper guards, and the bolts are black phosphate."
Perhaps it could be yet another change made sometime during the production year?
http://www.camaros.org/forum/index.php?topic=15233.0
:dunno:
Rob, as we know assembly line practice varies on occasion from what's stated in the AIM. All I can say is from the many original cars I've seen since the 2016 post, its my opinion that the fastener used on the bottom of the rear bumper guards is consistent with the photo above of Skip L's survivor car. I can't say if it has a blunt or chisel point as that can't be seen.
mhm1966
06-10-2021, 07:48 PM
Lloyd,
My bumper guards (03D of 1969) look exactly like post #13 with the silver cad hook and the bolt in either silver cad or zinc.
jl8z28
06-10-2021, 08:50 PM
I went through the legends the uppers are zink
jl8z28
06-10-2021, 08:52 PM
I mean silver cad
68camaroz28
06-11-2021, 02:36 AM
guard bolt
Bolt used for bumper guard bracket attachment clear zinc but lower bolt attaching bumper guard to lower panel phosphate. That is how Skip’s car is....
mhm1966
06-11-2021, 05:38 PM
Before I get my bolts plated, can we get an official answer on how the bolts that attach the bumper guards to the rear valance are plated.
jl8z28
06-11-2021, 05:44 PM
Phosphate
X66 714
06-11-2021, 05:57 PM
05A 12k miles car....Joe
Edgemontvillage
06-11-2021, 08:47 PM
Thanks for posting Joe, to clarify, shown in the photo are the standard, short style bumperettes vs the optional, long style.
X66 714
06-11-2021, 08:48 PM
Short. You're welcome....Joe
Enoch
06-16-2021, 03:31 PM
The lower bumper guard Bolts, I have seen two Styles. Some cars have a recessed head with a captured lock washer. But more cars than not have the captured flat washer. The application for the bumper guard should be zinc chromate. However this is the same exact bolt that attaches the starter brace to the block. And those were black phosphate. So it's possible that they got switched up at the factory on occasion or if they ran out they snag some from that bin
Edgemontvillage
06-21-2021, 09:29 PM
The lower bumper guard Bolts, I have seen two Styles. Some cars have a recessed head with a captured lock washer. But more cars than not have the captured flat washer. The application for the bumper guard should be zinc chromate. However this is the same exact bolt that attaches the starter brace to the block. And those were black phosphate. So it's possible that they got switched up at the factory on occasion or if they ran out they snag some from that bin
Thanks Rich. I also reached out to "JM" for his input on the question and he responded: "Silver Zinc, indented hex head with a floating washer. Standard and full rear guards used the same bolts"
X66 714
06-21-2021, 09:44 PM
I just got other pictures from another known original 69 z/28. Phosphate, exactly like to 12k original car....Joe
Enoch
06-23-2021, 03:20 PM
Here's a sampling of headmarkings for this application.
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