flat spot/stumble off Idle

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nick_m
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flat spot/stumble off Idle

Post by nick_m »

The mighty magic carpet aka my b310 a12 auto sunny has this somewhat annoying stumble when you take off from the lights with anything more than half throttle. It is just a big flat spot which is sometimes enough to stall it when its still warming up and even once warm it certainly has a good go.
I just did a service on it today new points,condenser, dizzy cap, rotor, and leads and did the tappets and timing while it was at it but it still does it.
Apart from burning a bit of oil it appears to be in good health
Could you guys shed the light on what you think couId possibly be causing it?
I was thinking since the thing is now 30 years old and completely standard its probably never had the carb off, I had thought about pulling the carb off and giving it a good clean out?
Bartman
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Re: flat spot/stumble off Idle

Post by Bartman »

Could be either an air leak, or a fualt with the accelerator pump?
They don't call me the man with the rubber arm for nothing you know.............
tsC20
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Re: flat spot/stumble off Idle

Post by tsC20 »

I have that problem too Nick with my A12. Sometimes over time a flat spot wears in the carburettor butterfly spindle and it doesn't open smoothly at times. just a thought, I havn't looked into mine very thoroughly yet.
nick_m
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Re: flat spot/stumble off Idle

Post by nick_m »

I had thought about a vacuum leak, I haven't had a good look but all the vacuum lines appear in good nick and have good connections.
I have a feeling its carb related, whether its the accelerator pump, its gunked up, it needs a tune or a combitnation of all three.
nick_m
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Re: flat spot/stumble off Idle

Post by nick_m »

tsC20 wrote:I have that problem too Nick with my A12. Sometimes over time a flat spot wears in the carburettor butterfly spindle and it doesn't open smoothly at times. just a thought, I havn't looked into mine very thoroughly yet.
You'll know what I mean then :)
Its not really a big issue, it would just be nice to sort it out.
Bartman
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Re: flat spot/stumble off Idle

Post by Bartman »

I had that problem 100 years ago with an old A12 I had. I just swapped the carb and the problem went away. Garth was selling a carb or two very recently, maybe see if he still has one?
They don't call me the man with the rubber arm for nothing you know.............
nick_m
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Re: flat spot/stumble off Idle

Post by nick_m »

Yeah could be worth investigating, athough as you will know dealing with 2nd hand 30 year old parts, I could get a carb with the same problem!
Dattochriswagon
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Re: flat spot/stumble off Idle

Post by Dattochriswagon »

We cant have a rough running Magic Carpet
nick_m
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Re: flat spot/stumble off Idle

Post by nick_m »

Dattochriswagon wrote:We cant have a rough running Magic Carpet
This is true!
Its always been there more or less, its just been bugging me recently, Its certainly a lot smoother now its had a good tune up
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