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Lean\rich knob on Johnson 6hp 1977

C

coteno

New member
First started my 1977 Johnson this morning (new super gaz , mix 1:50, gearbox into bucket)
I dont have the owner manual.
It start after 3 pull.

Question????
What is the initial setting of the knob ''lean\rich''?
How do it work?

Thank

Normand (Québec)
 
That is the low speed fuel mixture adjustment.-----Usually about a turn and half out from GENTLY seated.-----That keeps the motor running on first start.----Then you must adjust it for smoothest idle with motor warmed up and in forward gear.-----Make sure motor does warm up.-----The thermostats often fail in the open position on those.
 
coteno said:
First started my 1977 Johnson this morning (new super gaz , mix 1:50, gearbox into bucket)
I dont have the owner manual.
It start after 3 pull.

Question????
What is the initial setting of the knob ''lean\rich''?
How do it work?

Thank

Normand (Québec)
Click to expand...

The slow running needle is adjusted after removing the knob. If necessary, but if it starts , runs and idles properly with the knob in the middle of its adjustment range dont mess with it

If you need to , pull the knob off, screw the needle in until it seats very, very gently then back it out 1½ turns.

Start the engine allow it to warm up reduce the rpm to the absolute minimum then screw the needle in 1/8 turn at a time , reducing the rpm if it speeds up, until it falters. Then back the screw out again by up to ¼ turn to find the best position

Fit the knob in the centre of its range. Adjust the idle speed to normal

You should not then need to alter the setting but you can experiment to find the best position for starting together with the throttle opening

Be sure when running in bucket that the water level is several inches above the anti ventilation plate or you will risk not cooling it properly

You should only need regular gasoline but alcohol free if possible. A 2 stroke does not need the high octane stuff

You can get an owners manual from https://www.outboardbooks.com/
 
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If your adjusting in a barrel, you need to remove the cowling to help get fresh air to the carb. Why? The barrel accumulates heavy exhaust gasses and will cause a rich mixture and ineffective low speed adjustment. Sometimes I even use an electric fan to get air moving on a calm stale day. Many situations can change between shop and real life out on the lake.
Note: No high speed adjustment anymore. There is a fixed jet elsewhere in the carb. This can become partially plugged with fuel debris and symptoms include poor operation....fuel starvation.... at speeds above about 1000 rpm.
 
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Normand, send me your email addy in PM, don’t post your address, (bots might pick it up & spam you, or worse). I’ll send you a PDF factory service manual. It’s for a few years older than your ‘77, but most things are the same.
i also have the original owners manual, I can send you photos of the relevant pages, those years are not a very in depth manual.
As Vics said, make sure you have deep water in the tank. It has to be WELL above the cavitation plate, the pump won’t self prime.
Mines a ‘74 that I was given,
http://www.marineengine.com/boat-forum/showthread.php?467485-6HP-Evinrude-Fisherman-1974
 
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