[EDDIE110171]

I am rebuiling a carb and one of the jets was frozen and broke when I tried to remove it. I already drilled it out, now I need a tap to clean out the theads. For some reason it seems to be an unusual size. It is 32 threads per inch and the threads have a OD of .309". I can probably order the tap but nobody seems to have one in stock that I can just match up.
Does anyone know what size tap this would be? Any help will be appreciated.

[gt702]

Have you run the numbers in the metric system? Not sure what bike/car it is for so not sure what system.

I would think those are a special size, but have no experience with them. Good luck.

[G-Force Junkie]

If its a Jap carb its metric. 6 or 8mm are problay what it is, you'll have to do the math to convert the pitch.

[southpark460]

.75 or .80 mm probably...

[EDDIE110171]

It's off a Briggs & Stratton engine so it should be standard. The carb is a Briggs and Stratton 1 piece flow jet.

[cwr954]

Originally Posted by G-Force Junkie

If its a Jap carb its metric. 6 or 8mm are problay what it is, you'll have to do the math to convert the pitch.

there is no convertion for the metric taps the pitch is probably 6-8mm and the tread pitches for metric are 1.25-1.5-1.75 pitch

[sheepofblue]

An 8mm is approxiamately .314 so if the .309 is to the thread base it is likely an 8mm.

[gt702]

Originally Posted by EDDIE110171

It's off a Briggs & Stratton engine so it should be standard. The carb is a Briggs and Stratton 1 piece flow jet.

I don't have much experience with B&S, but don't have good confidence their carbs have standard threads for the jets (odd British stuff maybe )

or you can just bore it big and use JBWeld to make new threads?

[G-Force Junkie]

Originally Posted by cwr954

there is no convertion for the metric taps the pitch is probably 6-8mm and the tread pitches for metric are 1.25-1.5-1.75 pitch

What do you mean there is no conversion? Grab a caculator and you can easly convert 32 TPI to metric. That is what I was saying, I have never seen any M8 bolts with a thread pitch finer the 1.00mm, except for inside the thimble of metric micrometers. He said it was 32 TPI, my math puts that at a metric thread pitch of .0793 which is odd. Anywyays, I doubt any briggs and stratton carb in USA made, but it may be with inch pattern threads. My Machinist Handbook showes there is a 5/16-32 NEF, thats probaly what you got.

[G-Force Junkie]

Originally Posted by gt702

I don't have much experience with B&S, but don't have good confidence their carbs have standard threads for the jets (odd British stuff maybe )

or you can just bore it big and use JBWeld to make new threads?

Theres another idea, but I really doubt there would be a Whitworth thread in there, but then again I have seen strainger things. Ahhh the memories, Whitworth threads, Lucas Electronics, and a POS MGA I spent way too much time on