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By Hercules
#8926
Hi Friend, i have an Amal 376/29 Monobloc carb with following specs Needle jet 106, Pilot 30, Main jet 180, Slide #4 and Needle type C. I have installed it on my 1959 Royal en-field G2 350CC bullet, it is running rich with black smoke and within miles of riding , the spark plugs worn out.

I have tried following troubleshooting steps but no solution. First, i have changed Main jet to 160 and Pilot jet to 25. Still the problem persists. Then, i have ordered new Type C needle, Main jet 150, 140 and tried this new jets with new needle. Still carb is running rich and emitting black smoke also spark plug worn out.

Can someone help , what we can do for this issue.
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By Wheaters
#80232
Is the float height correct? Have you checked the that float itself is not leaking (and doesn't contain any fuel)?
By dave p
#80234
Check for wear in the needle jet. If the bore is anything but perfectly round replace it. A worn needle jet is a very common cause of richness.
By Hercules
#80235
Hi Wheaters, i have not opened the Float chamber yet, i am going to do that tomorrow. Will check and let you know.

@ Presto, thanks for your info. I didn't install any Choke items to it.

@Dave, Okay...I never thought of it. Will check that too.

@ all, Gentle mans, i have opened the same topic in Technical Message board on Hitchcook. hence, i would like you to reply on it, if any future suggestions.

Thanks for your valuable time.

By ric
#80263
I know it’s a frequent question asked with fuel related problems and Amal monoblocs, but have you recently fitted a washer below the fuel inlet banjo which raises the fuel height thus creating a richer mixture?

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