Another Carb Question. Float Needle Orifice chewed up

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Garnet
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Re: Another Carb Question. Float Needle Orifice chewed up

Post by Garnet »

ME 109 wrote:
Airbear wrote:
The easiest way would be to set up the carb with fuel coming in the top and the needle gently held against the seat. Imagine how little pressure the floats impose and duplicate that. Should give a pretty good idea.
What about a real world test Charlie? Like go for a ride and if yer can light yer boot when yer get back, there's a leak somewhere.

I'll never forget the day the two highway patrol cops suddenly start to back away from my bike when they see petrol pouring onto the hot right hand header pipe creating a cloud of white vapour.
Ah, back in the days before I repaired my carby seats. :mrgreen:
Still gave me a speeding ticket for $227! :cry:

"When there's nothing left to burn, you have to set yourself on fire!"
Orson Welles
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jjwithers
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Re: Another Carb Question. Float Needle Orifice chewed up

Post by jjwithers »

ME 109 wrote:The seats of both carbs look questionable in the photos from where I sit.
How can you tell the condition of the 'wall of the hole' if the seat is still in place?
If the 'wall' is damaged, your in trouble.
If the carbs were rare, they could be repaired with oversize seats.
The photo is the same carb, just two different angles. in the first photo, you can see that the seat is still unmolested. the wall is what's trashed.
I think i'll throw some floats back on and hook up a fuel line and try sending some water down the fuel inlet and see if they leak or not when the floats are up.
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Jean
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Re: Another Carb Question. Float Needle Orifice chewed up

Post by Jean »

DON'T USE WATER. Hey, use kero or something compatable with gas!! IF YOU DON"T WANT TO USE REAL GAS.
That is really the best way to discover if the SEAT is OK or not.
A seat can look fine and still leak badly.
Likewise, it might look like shit and be OK.
Clemson, SC
R100s, R75/5
ME 109
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Re: Another Carb Question. Float Needle Orifice chewed up

Post by ME 109 »

jjwithers wrote:The photo is the same carb, just two different angles.
:roll: Wake up Australia!

Ok, I was confused with your 'walls'.
Is the alloy carb body also damaged?

Changing the seat is no big deal, but there is only one way to do it, as mentioned.
If the carb body has been damaged, my thought would be to use some slow setting JB weld in a thoroughly clean and prepared way, just prior to installing the new seat. Potentially a little messy, so much control needed.
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jjwithers
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Re: Another Carb Question. Float Needle Orifice chewed up

Post by jjwithers »

I threw the needle in and it seals air and gas just fine.

It doesn't have clean left to right 'wiggle room' due to the goop along the sides but it works just fine going up and down.

I'm thinking it will work OK as long as it doesn't get stuck due to that goop.
www.beemersandbits.com
'77 R100S - http://www.joshuawithers.com/r100s
'73 /5 Toaster Cafe bike http://www.joshwithers.com/slash5
'67 Bridgestone 175 Hurricane Scrambler
'66 R60/2
'72 BMW 2002
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Jean
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Re: Another Carb Question. Float Needle Orifice chewed up

Post by Jean »

I like the flamin' boot test...
Clemson, SC
R100s, R75/5
JACK ETHRIDGE
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Re: Another Carb Question. Float Needle Orifice chewed up

Post by JACK ETHRIDGE »

I have a article on how to remove the neddle seat without using head using a tap and bolt. If you want a copy E Mail me at jackethridge@hotmail .com and i will send it. I can't figure pout how to attach it to my replay

Jack Ethridge
Ocala Fl
Jean
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Re: Carb rebuild info

Post by Jean »

Found this in my notes since you will be replacing stuff:
"When I started it the first time, the right side idle mixture needle leaked really bad. I took the Right hand carb back off and did some detective work on the O-rings. The O-rings for this needle and the idle jet are the same size (part number) but it is just too small and does not provide a tight fit in the bore. I finally bought (2) 4mm x 8mm O-rings from Advance and installed one on the leaking needle. No more leak. It was a snug fit."
This was using parts in a kit from Bing. I thought the O-rings were "curious" when I noticed they were alike but tried them anyhow. Bing had to know what they were doing, RIGHT?
NOT.
Be warned. Don't waste your time. If the O-rings you get for the idle mixture needle and the idle jet are the same size, go get some as noted above for the idle mixture needle.
Clemson, SC
R100s, R75/5
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