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Johnson 10hp QD16 1955

G

galen reid

Guest
" runs okay, it has been sitti

" runs okay, it has been sitting for a couple years but seems to be perking up the more I run it. However, I keep having to adjust the lean/rich knobs in order to get it to run at top speed. It has a tendency to stall when I give it gas from idle unless I goose it gently.I opened up the carburator and it seems to be pretty clean, except the float is corroded. How much of an impact does that make? Do you have any suggrstions? "
 
"Galen..... The carb is fouled

"Galen..... The carb is fouled, clogged, gummed, etc. Running the engine with the carb in that condition causes the engine to run lean. This will destroy the internal components of the engine.

Remove, clean, and rebuild the carb with a complete casrburetor kit, available at NAPA or your local dealership. Then adjust it as follows:

(Carburetor Adjustments - Two Adjustable N/Vs)

Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.

Setting the high and low needle valves properly:

NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle valve adjustment.

(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, waiting for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.

(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running. Eventually you'll hit the point where the engine wants to die out or it will spit back. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustments, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

Joe
"
 
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