carb adjustment on OMC 18 hp

[opposedtwin]

this is a model FD-11. i have for crap spark. i have cleaned the points, adjusted them etc and it’s still white, and not blue. it will fire but now i need to know the initial carb needle settings. i have a QD book and it says low speed out 2 full turns and high speed out 3/4 turn. it’s usually more out for the hs needle isn’t it?

as i pull it over it sneezes and pops.

please help. I’m about to bash this bastard’s brains in and set it on fire.

[wiscoboater]

low speed 3/4 out high speed 1 1/2 turns. Get it running and trim the settings from there. Best to do it on the water under load.

[wedgie]

Did you replace the caps?

[retiredoz]

One of my handy-dandys says low speed 1 1/8 turns, high-speed 1/2 turn.
i think that worked for me. Your sneeze-and-pop usually indicates too-lean mixture..

[legendre]

Start with the basics.. if you squirt a little pre-mix into the (open) carb or plug hole, and give it a pull, will it take off and run a few cycles cycles before it craps out?

Also I’m not sure why you’re moving on to carburetion when it sounds as if you have very little faith in the spark quality. If spark is inadequate, why would you move on?

[opposedtwin]

well, i don’t know why I’m moving on to be honest with you. it ran for a brief spell–30 seconds or so and crapped out again. i have done pretty much all i can do to the points save for replacing them. coils are new and test good. condensers were new when i replaced the coils. fuel drips out of the carb throat but the plugs don’t seem to get drenched. so I’m thinking maybe the float is sticking. i’ll take the carb off and go through it. shouldn’t have to replace anything, it was o/h a couple years ago. the cork like washer on the jet is old and I’d like to replace it. i have the buna rings for the RD models but not sure if they’re the right ones for this model. can anyone confirm or deny?

legendre: to answer your question, no it won’t fire when i spray into the carb throat. i have not tried spraying it into the plug hole. i was always told that was a no-no. the spark is big/robust looking but it’s white and not blue.

thanks for your help guys. this club is awesome! i always say it and it’s always true.

[opposedtwin]

quote Wedgie:

Did you replace the caps?

not sure i follow. what caps?

[wedgie]

quote opposedtwin:

quote Wedgie:

Did you replace the caps?

not sure i follow. what caps?

Caps (capacitors) = condensers. I see you have said you replaced them along with the coils. Maybe swap in some other points, even some used ones to see if anything changes. I know this may seem too obvious, but are the plug wires reversed?

[frankr]

Hm.m.m.m, fuel dripping out of the carburetor and won’t fire when you squirt more in. Sounds to me like it is TOO MUCH fuel. Called flooding.

[opposedtwin]

plug wires are not reversed. the points never need replacement in these do they? i have never on an OMC uni mag. maybe I’ve been lucky. I’ve got plenty of other used ones on junk mags. i’ll try it maybe.

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