What is the trick to start a 1977 Johnson 6hp?

tpenfield

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Mercury Power Tune is like Seafoam, but actually foams up and seems to do a better job or removing carbon from the cylinders.

What I did is run the engine for about 10 mins to get it warmed up ( that may be a show stopper right there, since you can not get it started :) )
Then I put the engine at a high idle speed and squirted the Power Tune right into the carburetor opening for a few seconds at a time . . . several times
Then I stopped the engine and took out the spark plugs and squirted more Power Tune into the spark plug openings.
I also soaked the spark plugs a bit in the power tune.
Spin the engine with the pull cord while the plugs were out to relieve any excess liquid from the cylinders.
Let it sit for about 30 minutes, put the plugs back in
Fired it up and ran it at a fast idle for about 5 minutes.

The comments about the throttle setting is on the twist handle, to set the throttle a bit higher than what you may have it set before pulling the starter cord.
 

flyingscott

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Go back to your mechanic and ask him to show you how to start it. You can't powertune it until you get it running.
 

Chinewalker

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Once the mechanic gets the carb knobs set, DON"T TOUCH THEM! They rarely need to be messed with. I suspect that changing them has thrown the carb adjustments out of whack to the point where the motor is difficult to start. As noted above, have the mech show you the starting procedure. That motor should start in one or two pulls every time.
 

jimwalt

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Thank you everyone for the tips/tricks. I took the motor to the mechanic this morning. He put it in the tank, used my gas can, primer bulb and fuel line and was able to start it after about 8 pulls. He said it was highly flooded, but somehow got it to start!. He's keeping it for the day and said he would figure out exactly what the correct combination is to start it (choke/throttle). He told me that I don't need to change the rich/lean setting when starting the motor, just if it starts running hard like in the spring or fall (with too much, or too little oil). Since I've had the boat/motor (a few weeks) I always use a 50:1 oil/gas mix. I was using some left over Penzoil 2-cycle that the guy I got the boat from gave me, when that ran out I got a small bottle of SuperTech from Walmart - But have heard that oil is crap, so going forward I'm only going to use the Johnson/Evinrude oil for this motor. Also I will be adding some of that Sta-Bil 360 Marine to each tank.

For the posts above that you all answered. I'm not doing anything with the carb knobs (there aren't any knobs). I was referring to the RICH/LEAN adjustment on the outside of the motor - Maybe that is what you are talking about?

Last week when he had my motor he said that they did a carbon cleaning treatment.Maybe that's the same as that Mercury Power Tune??? He also said that the spark plugs looked great so he didn't change them.

FlyingScott you said "Turn the low speed knob in until it lightly seats then turn it out 1.5 turns." - What is the low speed knob???

Wish there was a way to post a pic of the outside of my motor and throttle so you all could see what I have to work with.

Thanks again. Please keep the comments coming!
 

flyingscott

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The writing on the throttle is a suggestion only it seldom lines up where it needs to be. The knob on the front of your motor is for the low speed fuel/air mix.
 

jimwalt

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I'm an idiot! Mechanic showed me the trick.... throttle between start and fast (closer to fast), Choke out, pull rope. If it doesn't start on first pull leave choke IN then pull rope.

When I tried it at the shop it started 1st pull in three different tries!!

My problem was I had the choke out on every pull therefore flooding it.

He also taught me the trick to start with a flooded motor. Disconnect fuel line, choke in, pull rope till starts, reconnect fuel line.
 

jbuote

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Well at least you get to go out and have a weekend with your son soon!!
​Have fun with it!! :thumb:
 
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