Striped float bowl screws

[helmutholderbenz]

What size helicoiles do I need for my BS carbs float bowl?

[bwringer]

Do you mean the drain screws or the screws holding the float bowl to the carb?

[helmutholderbenz]

Bowl to carb

[jwhelan65]

Do you have a tap set? if so go a size bigger with a new screw.

[helmutholderbenz]

What size helicoil do I need for my float bowl on bs series carbs? Bowl to carb. Thanks for anyone's help

[habsdoc]

You may not have enough base material left to install the heli-coils. Why not just drill or ream the holes for the next size up screw size??? Would be much easier process.

[Skowinski]

You may not have enough base material left to install the heli-coils. Why not just drill or ream the holes for the next size up screw size??? Would be much easier process.

This is exactly what I have done. Just carefully drill out using the size indicated on the helicoil tap, use the tap to cut threads in the carburator body, and use the next larger size screw.

[tkent02]

Do they actually make Heli-coils that small?

[Agemax]

Do they actually make Heli-coils that small?

yep, i have fitted M3 helicoils before. The size in question is M4.

[bwringer]

yep, i have fitted M3 helicoils before. The size in question is M4.

Sorry, they're M5 on BS carbs, M4 on VM carbs.

They do make Helicoils that small, but there's not a lot of metal to work with.


There are claims of being able to solder or braze carbs with special rods, but I've never tried it or seen it done.

http://muggyweld.com/pot-metal-repair

[hampshirehog]

I would tap it to the closest imperial thread (7/32 I think but best do the maths yourself to be sure).

[fastbysuzuki]

I would tap it to the closest imperial thread (7/32 I think but best do the maths yourself to be sure).

What thread would 7/32 be?
been in engineering maintenance for way to many years but not come across that one be interested to know though.
never say never.

[Fjbj40]

8-32 is common in aviation.

[helmutholderbenz]

Well I got the Heilcoils installed in my carbs today. It was pretty easy, should not have any more problems as far as thats concerned. Found the right Heilcoils,(four threads) out of China, took awhile to get here(slow boat) but they were only six bucks and seem to be good quality, 30 coils! I did have to order the installation kit from the UK, it costs $15 and got here two days before the coils did. It came with 20 coils too but I could see they were going to be to long but I have them if I need them. All in all I'm very pleased with the outcome. glad I got this done.