Stud Replacement in original rear spoiler for '69?

[69Z28-RS]

Does anyone here have familiarity with replacing a broken stud in an original rear spoiler of a '69?   I'd like some information on how to remove the broken off stud, and source of a replacement stud and how it installs.  This stud may have been broken since factory installed it, and I don't want to damage the spoiler by my ignorance..  

Thanks,

Gary

[BlackoutSteve]

They are simply a double-ended stud with a 0.63" flange in between.
There is a course 1/4-14 self tapping thread on one end that taps into the spoiler, and a 1/4-20 thread for the nut.
The closest I have found is AMK's B-13780 (x3) (or B-13781 (x9))
These are OK for the front-most studs, but are a tad too long for the rearmost ones. I think the OE are 14-20 x 7/16-ish.

[69Z28-RS]

Thanks Steve;  I'll check out those parts... 

The rear ones are very short; the front ones are longer;  the nuts on the front are different from the nuts on the back as well.   AMK nuts  B-13436 appears to be identical to the nut used on the forward studs  (1/4 - 20 thread with a captive floating washer 3/4" D)...   The floating / captive washer on the rear most studs are smaller in diameter, but I haven't measured them or looked for the equiv AMK...

There was also a sealer (almost plastic like) around the stud at the hole thru the decklid.   Any idea what material should be used to reseal  when I reinstall the spoiler?

Gary

[BlackoutSteve]

For the sealer, I used AMK's B-11608. It's the same mastik-type-caulk that comes on many stamped nuts.
AMK also sell caulk washers which would be cheaper.
I buy the B-11608 because it does door water shields and a bunch of other stuff too.

The nuts I used are B-11679 and B-13436.

[69Z28-RS]

Steve,  The PN for the double ended stud you specified, are not exactly correct.
The four forward studs in the spoiler have 1" of length extending from the spoiler (I haven't been able to get the broken one out, nor have I removed one of the good ones to see what the length is which is screwed into the spoiler.   The rear most 4 studs in the spoiler are shorter, with 3/8" extending from the spoiler.   The nuts used for them are also different from the rear most to the forwrd most studs.   The forward studs (the longer ones) used a nut with a 3/4" floating/captive washer.   The rear most nuts have a smaller diameter captive floating washer (5/8" I think).   I have it written down in the garage..  and I'm typing from memory here.   I'm certain that these studs and nuts are original on my car.  I've tried to removed the broken off stud, but am thus far unsuccessful.... 

Gary

Gary

[BlackoutSteve]

Thanks.. My original reply did say the studs from AMK are too long for the rear.  I know because one of them touched the trunk gutter/tail panel..   Then, I found my OEs.. 

Also, I chose the nuts based on a post from John Z I think.. Could have been over at Camaros.net .
They were both identical nuts with captive washers but with the exception of the washer diameters.

[JohnZ]

Photos below show the forward and rearward spoiler nuts on my untouched/original 02D Norwood '69 Z/28 with factory D80.

[BlackoutSteve]

Thanks John.. Hey, weren't the domed nuts a late production amendment?

[tmodel66]

There was a change from the acorn nut to a regular nut with captured washer. My 07 A had the nuts and washer.

[69Z28-RS]

As does my 09C Z28, Daniel..   and I'm certain this is origiinal, and I believe when I removed the spoiler last weekend, it was the first time ever it had been off.  Unfortunately, one of the studs was broken off flush, and I'm uncertain how to remove the stud without damaging the fiberglass spoiler  I tried drilling into it with a 5/64 bit, intending to use an easy out, but I broke the bit off in it.. 

Does anyone have any ideas of suggestions??

Gary

[Sauron327]

Drill out the perimeter, remove the remnant and install a new one using 3M rigid parts plastic repair. Or weld a stud on the remaining piece and back it out. Even when you remove a stud, the hole gets damaged because of the stud's thread cutting design. I have to relocate the studs on repro spoilers because they are often installed incorrectly. You can't use just fiberglass resin for a repair, it has no strength.

[69Z28-RS]

the fiberglass isn't damaged.   but the long ext part of the stud was broken off flush.   I have removed the broken part by using a hammer and small chisel and gently tapping til it began to rotate..  I got it out without damaging anything.   I used the same technique to remove one of the good ones, so I can see the entire part..   I've attached a photo of it below.   The short end of the stud is 3/8" inch long and screws into the spoiler until the 5/8"  D flange stops it.   The long end of the stud is 1" long and is the external part that goes thru the decklid.   The screw threads are identical (1/4-20) on both ends of the stud  Today I went by Fastenal, but they have nothing like it.  Neither does the AMK catalog.   This may be one of those 'impossible' parts?   Does anyone have an old broken up *original* rear spiler that might still have a installed?   I only need ONE..  

Gary  / 69Z28-RS

[68Zproject]

If I don't get back to you right away remind me.  I have an original spoiler that I am going to sell and it might have a stud, but they might be no good too. I'll check when I get a sec.

[69Z28-RS]

Thanks 68Z..   If your spoiler is a '68, then the studs *might* be different?   The '69 spoilers had longer studs (1 " long) in the four position along the front edge of the spoiler, and 4 shorter studs along the rear edge.  The only reason I can see for the longer studs on the forward edge is to make it a big easier to get the nuts started since the studs are located where the deck lid reinforcement is about an inch deep?  I need the long one to be correct (1" exposed).   Once removed the short end  that goes into the spoiler is 3/8" long.

Gary

[flyingskibiker]

http://www.parts123.com/parts123/yb.dll?userwatch%7EdynamicSearchPage%7Ecadeiije
(www.oldmusclecars.com = Classic Muscle Car parts)

Studs: PN 1478SK
Mounting hardware: PN 14789H

You be the judge if they are correct.  But this is what they are all selling...