Hi all,
Wondered if I could pick some of your brains on this issue and see what you lot think.
While servicing my 1641(with twin carbs)I was inspecting the spark plugs and found that plugs 1 and 2 are rather black and sooty compared to 3 and 4 which are perfectly chocolate colour.
I proceeded to fit my gunston colour tune to the cylinders 1+2 to check the carb balance. As expected the colour tune was glowing orange, rather than the blue colour required.
I then checked the plugs 3 and 4 which as expected showed they were glowing blue.
This in my head was a positive sign that the carb was out of balance for cylinders 1+2. I re attached the colour tune to the problematic cylinder and adjusted the carb till colour tune changed from orange to blue.
However now the bus is backfiring so I have set the mixture screw halfway between the the original setting and the new. This has stopped the backfire but the colour tune is not 100% and not sure exactly why this is happening?
I also should mention that in the past I have fitted an electronic ignition with flame thrower coil, and upon recomendation opened the plug gap to 0.30 from 0.25.
Bus has been running fine with no obvious issues before the service.
Cheers
Sent from my SM-N910F using Tapatalk
Wondered if I could pick some of your brains on this issue and see what you lot think.
While servicing my 1641(with twin carbs)I was inspecting the spark plugs and found that plugs 1 and 2 are rather black and sooty compared to 3 and 4 which are perfectly chocolate colour.
I proceeded to fit my gunston colour tune to the cylinders 1+2 to check the carb balance. As expected the colour tune was glowing orange, rather than the blue colour required.
I then checked the plugs 3 and 4 which as expected showed they were glowing blue.
This in my head was a positive sign that the carb was out of balance for cylinders 1+2. I re attached the colour tune to the problematic cylinder and adjusted the carb till colour tune changed from orange to blue.
However now the bus is backfiring so I have set the mixture screw halfway between the the original setting and the new. This has stopped the backfire but the colour tune is not 100% and not sure exactly why this is happening?
I also should mention that in the past I have fitted an electronic ignition with flame thrower coil, and upon recomendation opened the plug gap to 0.30 from 0.25.
Bus has been running fine with no obvious issues before the service.
Cheers
Sent from my SM-N910F using Tapatalk
