Bolt of the day 10/3/11 JH head mark

[Christopher A.]

Ok, this bolt really has me confused. I have performed several frame off restorations and i have never seen a bolt like this on a Corvette. Perhaps it just ended up in the bolt box by mistake, but perhaps not.

As per usually, i will post the year and engine of my car.

66 427/390hp California car with A.I.R. and T.I.

-JH head mark 3/8-16 thread size, partially threaded. No indication of other marks that would give the strength rating of the bolt, so I assume it was not used on the suspension system, but instead might be to hold a component in place.

-Length is approximately 1" when measured from under the head of the bolt to the end.

-Threaded portion appears to be roughly 7/16" in length, non threaded portion is around 9/16" in length.

-Thread size is 3/8-16 course thread

[Terry M.]

Re: Bolt of the day 10/3/11 JH head mark

John Hinckley ??

J/K

[Gary J.]

Re: Bolt of the day 10/3/11 JH head mark

Must be bolts that were left over from the Viper plant where John worked.

[John H.]

Re: Bolt of the day 10/3/11 JH head mark

Obviously, my favorite bolt . I have one too (photo below), but it didn't come from a Corvette; it came threaded into a 4"-long piece of zinc-plated steel tubing that came with a dozen fiberglass driveway marker rods, for use as a tool to drive them into the ground with a hammer. I think the Grade 5 would be adequate for that usage .

[Michael G.]

Re: Bolt of the day 10/3/11 JH head mark

John only has a bolt, I've got whole car, albeit, a POS British car....

Ignoring the initials, that's a strange bolt Chris. It had to be made with particular purpose in mind, hence the bulge between the head and the threads. That bulge had to be put there by the thread rolling dies, which normally do not touch that part of the shank. I'd guess someone put it there to hold a seal up against the head. That, and the very short thread length, tells me that it probably was probably more of plug than a bolt.

[Joe L.]

Re: Bolt of the day 10/3/11 JH head mark

Ok, this bolt really has me confused. I have performed several frame off restorations and i have never seen a bolt like this on a Corvette. Perhaps it just ended up in the bolt box by mistake, but perhaps not.

As per usually, i will post the year and engine of my car.

66 427/390hp California car with A.I.R. and T.I.

-JH head mark 3/8-16 thread size, partially threaded. No indication of other marks that would give the strength rating of the bolt, so I assume it was not used on the suspension system, but instead might be to hold a component in place.

-Length is approximately 1" when measured from under the head of the bolt to the end.

-Threaded portion appears to be roughly 7/16" in length, non threaded portion is around 9/16" in length.

-Thread size is 3/8-16 course thread

Christopher------


I have seen this "JH" headmarking on hardware store bolts, although this bolt does not appear to be otherwise configured like a hardware store bolt.

I think the "JH" indicates a foreign manufacturer. Taiwan, China, or Korea, I think.

[Christopher A.]

Re: Bolt of the day 10/3/11 JH head mark

I have also seen the JH headmark on bolts at the local Hardware store. However, these are old and were re-plated with the rest of the stash that came with the car.
Im pretty sure they do not belong to the Corvette or perhaps any car for that matter, but i thought i would ask just in case someone had seen them before.
I will file them with the rest of the unidentified bolts that most likely do not belong to the car.

Thanks

[Ronald L.]

Re: Bolt of the day 10/3/11 JH head mark

Seen lots of them at Home Depot.