I have a few carb questions:
1. Does anyone know how many CC's the float bowls should hold when the floats are adjusted correctly?
2. I have a float bowl screw hole stripped out. What is the original screw size and thread - and what would be the next size up?
Thanks in advance for any help.
Float Bowl
- dingdong
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Re: Float Bowl
Not sure about float fuel CCs.
Original JIS screw size in mm is 4x70 Next size up is 5x80. Be very careful when tapping the carb bodies. The cast aluminum alloy can fragment at the threads if you work too fast or don't use cutting oil. Slow and careful. There is so little extra material around the holes you only get one size over to get it right. I messed up a couple when I attempted to tap mine. Ended up going with Heli-Coils and using the original screw size.
Original JIS screw size in mm is 4x70 Next size up is 5x80. Be very careful when tapping the carb bodies. The cast aluminum alloy can fragment at the threads if you work too fast or don't use cutting oil. Slow and careful. There is so little extra material around the holes you only get one size over to get it right. I messed up a couple when I attempted to tap mine. Ended up going with Heli-Coils and using the original screw size.
- landisr
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Re: Float Bowl
In a pinch, you could try filling the hole with JB Weld, letting it set up, then drilling and tapping with the stock size. I don't believe those screws are intended to be torqued tight enough to pull through. Others might know more about it and will chime in...
Ron in AZ
Ron in AZ
I'm not so sure about an inner child, but I have an inner idiot that surfaces every now and then.. 

- Maz
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Re: Float Bowl
If it's the screws that hold the bowl on, use a Helicoil kit to re-thread them back to original size. I have done this on 2 of my carbs and it works perfectly.Steve01 wrote: ↑Mon Sep 24, 2018 4:16 pm I have a few carb questions:
1. Does anyone know how many CC's the float bowls should hold when the floats are adjusted correctly?
2. I have a float bowl screw hole stripped out. What is the original screw size and thread - and what would be the next size up?
Thanks in advance for any help.
Maz
Ironically, Common Sense is the LEAST common of all senses!