Honda 50 Running Rough on Idle

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Paulieb
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Honda 50 Running Rough on Idle

Post by Paulieb »

Just finished changing the oil, filter, lower unit oil, and plugs in my Honda 50 this weekend. The engine started on the first crank but seems to be running rough in idle, accoriding to the tach the idle is currently about 250-350 RPMs. I used stabilized fuel all last season and drained the carbs for winter. Any ideas what would cause this rough idle? What should the idle be set at? Does anyone know where the idle set screw on a Honda 50 is located? I did see a procedure to "sync" the carbs, but it looks like you need special equipment, has anyone done this or do I need to bring it to a mechanic? Thanks in advance for any ideas.
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Timm Miller
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Honda 50

Post by Timm Miller »

Is your gas fresh?.......I know you said you used Stabil but is your gas fresh? The idle rpm's should be 900-1000 rpms. The adjustemnt screw is located at the very bottom carburator......follow the linkage to the very bottom....you will notice it faces up and backwards some......much different then the others in the linkage. You want to make sure the motor is warmed up before you adjust it.
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Captain Jim
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Post by Captain Jim »

Paulieb,

Check this thread out, it should help you:

http://macgregorsailors.com/phpBB/viewtopic.php?t=10490

The idle adjust ment is located at the bottom of the vertical carborator linkage. Turning the adjustment screw in the clockwise direction increases the idle. Set your noload idle adjustment around 750 - 800 rpm and you should be fine under operating normal conditions. I just went through this process at the beginning of May and things are good.

Fair winds,

Jim :macm:

S/V BOLD VENTURE
Kelly Hanson East
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Post by Kelly Hanson East »

Paul - tachs are notoriously inccurate at low rpms - I doubt the engine would even run at 250 rpm. Sure sounds like a fuel thing though.
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Paulieb
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Post by Paulieb »

Yes - the gas is fresh, filled the tank the same day. I think the idle is just set too low I hope. When I adjust the fuel manually from the helm it seems to run great. With the low idle, the engine stalls when coming out of gear and going to nuetral.

Thanks for all your help, can't wait to get home and try to adjust the idle.
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Uncle Jim
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Post by Uncle Jim »

I've had the same problems, fist is the obvious; gas, try a different tank of fresh gas (stabilizer is only to keep the gas from thickining does not keep the water out). Second is the vent open and the bulb hard (guilty on at least one count of each). Now for the fun stuff! adjusting the idle is easy, on the starboard side of the eng there are the three carb bowls with a linkage between the three. They all have an adjustment screw but the lowest carb (#3) is the one you'll turn for adjusting the idle. But make sure that the eng is running smoothly or you'll have problems with missing and a lack of top end.

If the eng is not running smoothly with fresh gas and a clean tank, you have a plugged injector or a dirty carb bowl, a rebuild kit cost at $12 you'll need three. Takes a couple of hours to install. I also installed a second fuel filter (glass type) in the hose so that I can see if there is any dirt in the line without taking the hole thing apart.

Jim
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