Timing/Carb Adjustments on 1963 Johnson FD17M 18hp

5oldjohnsons

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Apr 23, 2011
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11
Wondering if any of you guys can tell me how to set the timing and what are good starting points for carb adjustments. When trying to start right now it will spit out the exhaust like its backfiring. Actually got it to start with a little bit of starting fluid and ran ok off idle.(i'm running it in a barrel so i don't know how it runs under a load.) But as soon as I roll the throttle back down it starts spitting/backfiring and dies.
 

F_R

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Jul 7, 2006
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28,226
Re: Timing/Carb Adjustments on 1963 Johnson FD17M 18hp

There is no timing adjustment other than breaker points gap, set to .020"

Spitting and sneezing at idle is caused by running too lean. Give the slow speed needle a tweak to the left. If that doesn't fix it, the carburetor is dirty and need a good cleaning (especially since you have to use a snort of ether to get it going). Initial settings are 3/4 turn open on the high speed and 1 1/2 turns on the slow speed. Must be adjusted on a boat on the lake after that.
 

5oldjohnsons

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Apr 23, 2011
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Re: Timing/Carb Adjustments on 1963 Johnson FD17M 18hp

Thank you much, have one more question. I only see one adjustment on the carb and its the one on top of the carb attached to the knob next to the choke lever. Is this the slow or high speed and where is the other one?
 
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