coppercutlass

So my buddy drops off his 72 chevy c/10 for me to buff the whole truck and mess with the carb since he could not figure it out. I know I know not an olds but carb issues can be universal so I find it fitting. It has one of those holley 4100 style summit brand carbs. Well Off the bat the rear fuel float was wayyyyyyyyyyyyyy high. So I took it to my dads shop so I can tune and test it in their long alley along side their shop. First order of business was adjust the fuel float. Well that's when things went horribly wrong. I found out why that float was adjusted so high. Someone had messed up the threads and it would only tighten with the float all the way up as soon as I started adjusting it I knew something was wrong. I took the carb off and I tossed on the 650 holley double pumper from my 72 and it worked with out turning a single screw. Now after that lengthy explanation. Here is my question. Is it possible to helicoil a machine thread that's that small. I don't know the thread size of the needle and seat assembly. I have never used heli coils . My friend said if the carb was not worth messing with he would buy a 650 but im determined to make his carb work it could have been as simple as adjusting that fuel float which I suspected was the issue. I got all excited to fine tune his set up and did not want to use my carb so much for that lol.

nsnarsk65cutlass

Probably better off getting another float bowl.Nick

coppercutlass

No can do . if it was that easy I have a small bucket of misc. carb parts I could have cleaned one up. this is an older style carb where it has a top lid and the lid holds the floats and the bowls are in the lower half of the carb. kinda like an edlebrock / carter.

coppercutlass

My mistake I accidentally typed 3310 I mean 4110 holley or 4100 autolite style carb

nsnarsk65cutlass

Ok i though it was a Holley.i don't know how small or fine of thread helicoil that's available sorry.Nick

coppercutlass

It technically is a rebranded holley. Looks like this. I guess I'll have to go by the napa and see if they have anything or offer anything that small.

5998DownUnder

Any chance of a photo of the dodgy part?

MDchanic

I'd try to ID the thread pitch and diameter with a thread gauge and/or a set of taps and dies.
If you can't scare up the right ones, NAPA may have the ability to gauge the thread even if they don't have the HeliCoil for it.
Once you know the size you're looking for, a web search will probably turn it up. HeliCoil makes a LOT of different sizes, but they're not all available at your local store.

Good luck!

- Eric

Fun71

Agreed. I highly doubt Holley or whomever designed a proprietery thread for that carb, so it should be something that HeliCoil has in their inventory.

coppercutlass

Thanks guys my buddy is going to heli coil it he said they stock them at his shop. I'm also rebuilding a 650 holley dp that his neighbor gave him . He was really pleased with how well it ran with the 650 from my 355 so its on there since my heap is out of commision.