Carburetor studs

[CG]

When I took the two barrel carb off to have it rebuilt it was held on with with two bolts, one stud and nut (semi broken off and rusted tight) and one broken off something. I looked in the assembly and service manuals and looks like it was originally held on with stud nut combo on all four corners. Can someone tell me what thread size and length these studs are supposed to be?

[dave2953]

I'm not certain of the size, but when I needed them for my 2bbl I got them from the help section at the local parts house.

[eedgell]

Most all carb studs or bolts that I have seen have been 5/16 diam. and course thread. If studs are used then the studs are 5/16 course into the manifold and 5/16 fine to the carb side.

[dave2953]

Just found the part I was talking about online. Says they are 5/16"-18. Is 18 the pitch?? Here's a link to the site:

https://www.dormanproducts.com/cgi-b...tegory_list=:0

[Shane]

18 is the pitch ... what "pitch" means is how many threads per inch ... in other words, if you measured a one inch length of the stud, and then counted the threads you would have 18 in that length.

Here's another machinist trick and a pretty cool little helpful hint ... if you ever need to know the decimal equivalent just divide 1 by the pitch.

example:
1 / 16 = .0625
1 / 20 = .0500
1 / 24 = .0417

You may be asking yourself "Why the heck would I ever need to know that?" You may not, but just in case, this is the measurement from the top of one thread to the next. In other words, for a 5/16"-18 thread, it is .0625" from the crest of one thread to the crest of the next.

[dave2953]

Thanks for the info Shane! I was wondering how to figure that out.

[CG]

Amazing how much you can learn on this site...thanks