Topic: What kind of bolts are these
in Forum: C3 Engines, Driveline and Handling
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BURBANK, WA - USA
Joined: 12/21/2004
Posts: 59
Vette(s): 1981 Frost Beige Coupe... all original.. My SECOND Love...
OK, I tried to post a picture 3 times, but in a world of Microsoft security and pop-up blockers I can't seem to figure out how to make it work...
I'm working on removing the half-shafts on my 1981. The u-joint caps are held on by these small bolts with funny looking heads. They are not Hex nor Allen heads. I have seen these bolts before, but I don't know what they are called or what tool is needed to remove them.
If you have an idea, I would be most greatful...
Thanks!!! Carl
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Duncanville, TX - USA
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They are inverted torx bolts. Don't remember the exact size, but I'm sure someone will confirm that...
Shame on you Dave, for posting such a large pic...of a really kewl car...
Shame on you Dave, for posting such a large pic...of a really kewl car...
Joel Adams
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[QUOTE=Adams' Apple]They are inverted torx bolts. Don't remember the exact size, but I'm sure someone will confirm that...
Shame on you Dave, for posting such a large pic...of a really kewl car...[/QUOTE]
Shame on you Dave, for posting such a large pic...of a really kewl car...
[/QUOTE]
Never heard them called inverted torx, we call them twelve pointers here. You just need to use twelve point ring spanners (wrenches) to undo them. If your wrench kit only has hexagonal rings, they won't work. They are all the same sizes as the normal hex AF sizes. I think the U joints are 1/2".
Former Member
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BURBANK, WA - USA
Joined: 12/21/2004
Posts: 59
Vette(s): 1981 Frost Beige Coupe... all original.. My SECOND Love...
Ok.. I admit that I was having one-of -those-days.. Thanks for the info. They had a set of wrenches at Sears...
Lifetime MemberModerator
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20225
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
I have seen some of the 81-82 cars with 1/4" 12 point bolts there, but from what I can tell, they were replaced before. The ones I've seen that were "original" to the car have all been inverted torx head bolts. I may have a couple I can snap a pic of.
What type of wrench did ya wind up using, Bob?
What type of wrench did ya wind up using, Bob?
Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
Former Member
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BURBANK, WA - USA
Joined: 12/21/2004
Posts: 59
Vette(s): 1981 Frost Beige Coupe... all original.. My SECOND Love...
I took your advice and went to Sears and got a set of Torx Sockets. The second smallest one fit perfectly and with a few grunts I got the passenger side off. 
I may replace them with allen head bolts if I can find some that small.. Thanks for the help!
Carl
Lifetime MemberModerator
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20225
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
There are replacement bolts for this, that are 1/4" head, 12 point type. They are also used in...ahem...Chryslers...and Yeeps. 
The problem with those is, the heads tend to round off quite easily.
Don't know how many of them sobs I've had to drill out over da years...
What size was the socket? Was it 7mm...5mm? Inquiring minds want to know!(and my declining mind can't remember!)
The problem with those is, the heads tend to round off quite easily.
Don't know how many of them sobs I've had to drill out over da years...
What size was the socket? Was it 7mm...5mm? Inquiring minds want to know!(and my declining mind can't remember!)
Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
If the bolts are original they are just 1/4 inch 12 point hex. bolts. 
You have to have a 12 point socket or wrench to fit them, a standard 6 point won't work.
You have to have a 12 point socket or wrench to fit them, a standard 6 point won't work.
The only other head type that I can imagine them being would be an inverted torx. (not likely) GM has changed them to hex. My guess is they're 12 pnt.
in Forum: C3 Engines, Driveline and Handling
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