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carb problem

Ok , so I set the timing by the book , adjusted carbs and it idled at 1100 rpm. Then I backed off the Idle screw and got the rpm down to 750 rpm . This retards the timing quit a bit but seems to Idle good and increased throttle works good. Am I doing this right or is retarding the timing going to hurt anything ???? First time setting up an outboard. Am I learning
 
Once you get it out on the water you will need to final the idle adjustments in forward gear after running it at hogh speed for five or so minutes. Then you should not have to touch it until the nest carb service. Always check/adjust engine sync when you pull the carb.
 
It is always best to error on the rich side of the slow needles to protect the engine at slow speeds it helps with cold starts and the hole shot.
 
If you read the manual it specifically says to error on the rich side when adjusting the slow needles. Too lean means running low on oil and you can score thecylinder walls running extended periods low on oil. Go from slow to fask quickly if it hesitates add 1/8 turn rich on the slow needles and try again. Once you get a clean hole shot you should be good.
 
You stated that a motors may need more oil at idle.----Motors with automatic oil injection often cut back on the amount of oil going into the fuel at idle.
 
The point is 2 strokes , conventional or oil injected do not need more oil at idle as was stated !
 
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Uh.....premix is 50:1 not matter what needle setting is, all you are doing is changing the air/fuel ratio not oiling.
 
faztbullet said:
Uh.....premix is 50:1 not matter what needle setting is, all you are doing is changing the air/fuel ratio not oiling.
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So your saying there is no oil in the fuel? I’m confused by this reasoning you can put smaller high speed jets as long as the fuel mix is 50:1. Remind me why i should let you touch any of my engines?
 
The point is that you are saying to richen the low speed needle to PROTECT the motor.----You imply that a motor needs MORE oil at idle.----We are saying that is not true.
 
That page does not mention that " damage " will occur !-----You said ---" too lean means running low on oil " in post #38----That simply is not true !----Motors can run well with less oil at idle.-----Lean scoring is something that happens at full throttle and full load.
 
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So your saying there is no oil in the fuel?
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Nope...said its 50:1 not matter the setting...adjusting needle changes air/fuel ratio not whats mixed in fuel..

I’m confused by this reasoning you can put smaller high speed jets as long as the fuel mix is 50:1
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You answered your own question as adjusting needle is similar to changing jets...your changing the AFR(stoichiometric air fuel ratio). And just because ratio is 50:1 doesn't mean you can use smaller jets.
Remind me why i should let you touch any of my engines?
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....Because I know how to fix them
 
Agreed. The lack of an acceleration pump in most OB carbs requires a richer than normal idle to prevent bogging.

Jeff
 
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