Off-Idle Bog/Hesitation/Stumble: Let's figure this out with Science!

All the work you do in the workshop. Maintenance, repair, troubleshooting, customizing, etc.
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radare
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Re: Off-Idle Bog/Hesitation/Stumble: Let's figure this out with Science!

Post by radare » Thu Jul 13, 2017 10:44 am

Some observations while doing this:

The engine will not idle smoothly until the pilot jets are set consistently at a particular A/F ratio. Setting all carbs to 14.7 results in a very smooth idle.

Changing pilot jets independently from this setting will cause the idle to roughen out again. But changing all pilot screws the same amount, consistently, does not impact idle.

The pilot screws are much more tunable as they are screwed out further. In the 1-3 turn band, small adjustments in the pilot screw results in wide changes to the A/F. That is, a 1/16 turn in the screw might result in an A/F moving from 16.6 to 12.1. However, after about 3 turns out, the screws can be easily adjusted to meet a certain A/F ratio.

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Casper
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Re: Off-Idle Bog/Hesitation/Stumble: Let's figure this out with Science!

Post by Casper » Thu Jul 13, 2017 11:27 am

That is good to know. Interested that the suggestion was to go to 2.5 turns out instead of something a bit of 3.
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