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

[jimwalt]

I'm a first time boat owner. Three weeks ago I got a 12' row boat with a 1977 Johnson 6hp. The seller gave me a 5 minute course on how to start it.

Since that time I and my 7 year old son have went about 7 times. Each and every time I have to pull the rope 10+ times to get it to start. Last week I took it to a very reputable boat motor service center and have it looked at. They said it was one of the best cared for from that time era they have seen. They have been in business over 30 years too!

They cleaned the carberator did a few other very minor things I was told. The spark plugs looked good they said, so they were not changed. Not sure if anything else was actually done. When I went to pick up they showed me how to start it. They had it in a huge tank and the 1st pull it started.

Yesterday I and my son were going to go out and fish. I thought I should maybe verify it would start by doing it in a bucket. After about 6 to 10 pulls if finally worked and we went out. Today we went out again, got to the lake and into the boat..... I pulled, waited, tried EVERYTHING for over 1 hour and couldn't get the darn thing to start. I'm glad I had oars so I could get back to the dock. Nothing like this to ruin your Sunday and feel like a looser in front of your little boy!

Seems it had to be a fluke that the service center got it to start with 1 pull. That has NEVER happened for me.... but I wish it would.

So what's the trick?

I have it in Neutral, Choke all the way out, Lean/Rich set just as the service center left it 12PM and 6PM, Primed the gas ball till firm (and verified gas was going into motor by removing connector outside motor).

I just can't figure the darn thing out and need an education. So instead of sitting on the lake now, we are back home sitting on the couch typing this.

Thank you VERY much for your help!!!

 

[flyingscott]

You need to turn the throttle towards fast try about a 1/4 or more with the choke out and primer bulb pumped.. If the motor is cold you will need to start it using the cold start procedure every time. If it is still a warm motor you will still need to use the throttle.

 

[jimmbo]

deleted

 

[F_R]

You need to turn the throttle towards fast try about a 1/4 or more with the choke out and primer bulb pumped.. If the motor is cold you will need to start it using the cold start procedure every time. If it is still a warm motor you will still need to use the throttle.

My thoughts exactly. The "Slow-Start-Fast" label on those motors' tiller handle are never accurate. Put it a bit above the "Start" position. You will soon get the hang of it and know what it takes.

 

[oldboat1]

Maybe over choking.

Might run over to NAPA or AutoZone and pick up an adjustable spark tester, open air type. Remove both plugs, and test top and bottom wires for spark. Set the tester at about 3/8 inch, and make sure it has a solid ground connection.

no kill switch on that one, unless a PO installed one -- think there was an accessory kit. (could be problematic or at least an issue -- cuts off spark)

 

[xjdriver]

my 1975 would usoully start within 1 or 2 pulls cold. I advance the throttle to full then back it off about 1/4 turn prime full choke and as soon as it tries to start push choke in to half choke once its running throttle it down near idle and after a few seconds take choke off. if your still having trouble after reading these posts there is something up with the motor.

 

[tpenfield]

I have difficulty starting my 1980 Johnson 4.5 HP . . . usually takes 5-6 pulls. I agree, maybe a bit more throttle when trying to start it. I found that the engine I got (used) had a lot of carbon built up in the cylinders. So, I treated the cylinders with some 'Mercury Power Tune' and it seemed to improve things.

My 1969 Mercury 7.5 HP starts second pull pretty much every time.

 

[F_R]

BTW, ignore what the book says about the recoil starter. Give it a yank. Just not a LONG yank (don't yank it out by the roots).

 

[jimwalt]

You need to turn the throttle towards fast try about a 1/4 or more with the choke out and primer bulb pumped.. If the motor is cold you will need to start it using the cold start procedure every time. If it is still a warm motor you will still need to use the throttle.

Thank you. I'm really not sure I understand. Let me take it step by step.......

Throttle says Fast, Start, Shift, Slow, Stop (I believe). - So move between Start & Fast
Pull Choke all the way out
Pump the gas primer until firm
Pull rope.....
I've tried that countless times and it just doesn't work for me.

What do you mean "If it is still a warm motor you will still need to use the throttle"? Yes, I would put it on "Start"... I don't understand.

 

[flyingscott]

more throttle. Depending on water temp a motor could stay warm for 15 min to 1/2 hr where you would not need to use the choke again.

 

[jimwalt]

My thoughts exactly. The "Slow-Start-Fast" label on those motors' tiller handle are never accurate. Put it a bit above the "Start" position. You will soon get the hang of it and know what it takes.

"Above the Start position" means???? Mine says Stop - Slow - Shift - Start - Fast

 

[jimwalt]

Maybe over choking.

Might run over to NAPA or AutoZone and pick up an adjustable spark tester, open air type. Remove both plugs, and test top and bottom wires for spark. Set the tester at about 3/8 inch, and make sure it has a solid ground connection.

no kill switch on that one, unless a PO installed one -- think there was an accessory kit. (could be problematic or at least an issue -- cuts off spark)

Yes, mine doesn't have a kill switch. Just the spots on the throttle. I have to move it to Stop.

 

[jimwalt]

I have difficulty starting my 1980 Johnson 4.5 HP . . . usually takes 5-6 pulls. I agree, maybe a bit more throttle when trying to start it. I found that the engine I got (used) had a lot of carbon built up in the cylinders. So, I treated the cylinders with some 'Mercury Power Tune' and it seemed to improve things.

My 1969 Mercury 7.5 HP starts second pull pretty much every time.

How do you treat the cylinders? Can I do that and also with the "Mercury Power Tune"?

 

[jimwalt]

Is it possible to "flood" the engine by pulling the rope too many times? If so, how do you remedy that? Does it just need to sit for some time (how long)?

Thank you again everyone for your help.

 

[jimwalt]

​When you can't get the motor to even turn over, then how is it possible to give "more throttle"? Thank you.

 

[jbuote]

I could be wrong, but I think what they're trying to tell you, is to turn the grip more towards "Fast"..
​As long as you're in neutral, you need to find the "Sweet Spot" between start and "Fast" where you're engine wants to start the easiest.
​So, "More Throttle" in this case, means more towards "Fast" even though the engine isn't running.. Kind of like stepping on the gas pedal in your car to help it start (Old carb type.. LOL)...
You're giving it "More Throttle" to help it start...
​It was mentioned the stickers indicating "Start, Fast, Shift, Slow" etc.. Aren't always accurate..

​Sounds like you might want to play with your initial throttle setting and see where it wants to start.. Kind of a trial and error thing...

​Not trying to step on any toes... Just hoping to help clarify a bit.. That is, If I understood what they were trying to tell you...

 

[jimwalt]

I could be wrong, but I think what they're trying to tell you, is to turn the grip more towards "Fast"..
​As long as you're in neutral, you need to find the "Sweet Spot" between start and "Fast" where you're engine wants to start the easiest.
​So, "More Throttle" in this case, means more towards "Fast" even though the engine isn't running.. Kind of like stepping on the gas pedal in your car to help it start (Old carb type.. LOL)...
You're giving it "More Throttle" to help it start...
​It was mentioned the stickers indicating "Start, Fast, Shift, Slow" etc.. Aren't always accurate..

​Sounds like you might want to play with your initial throttle setting and see where it wants to start.. Kind of a trial and error thing...

​Not trying to step on any toes... Just hoping to help clarify a bit.. That is, If I understood what they were trying to tell you...

Thank you very much! Yes I have tried on Start, a bit between Start and Fast, and really close to Fast............ No luck.

I do wonder if it has something to do with the Rich/Lean knob? I read that you have to have EXACTLY the right mix of gas/oil to get it started as well.

What a way to ruin a Sunday with my 7 year old in the boat and dad can't start the motor. :-(

 

[flyingscott]

​When you can't get the motor to even turn over, then how is it possible to give "more throttle"? Thank you.

Turn the handle towards fast until it stops.
If it floods turn the handle towards fast and push the choke in and pull until it starts.
Turn the low speed knob in until it lightly seats then turn it out 1.5 turns.

 

[jbuote]

Dang... That stinks!!

Well, I saw it mentioned that maybe it's "Over Choked"...
Have you tried different choke settings combined with different throttle settings?
​Maybe try 1/2 choke instead of full out... Or Full choke for a pull or 2, then 1/2 or something....

​If the mixture is set where the shop had it, and it started on pull 1, I wouldn't change it..
​Gut is telling me it's a choke AND throttle combined initial setting that needs to be found..

​I'm by NO means an expert, but you had it running...., The shop did too...
​Sounds really like it's a matter of learning what the engine wants... Once you find that combo, bet it'll start first pull every time...

​Maybe even call the shop tomorrow, and ask them how the heck they got it started in 1 pull...

​I'll leave it to the others now, but sorry you had a bad Sunday... :facepalm:

 

[oldboat1]

The knob controls carburetor air/fuel mix. Lean is less fuel, rich is more fuel.

The oil "mix" is another matter. It's a ratio, 50:1 on yours. That means 3oz of 2-cycle oil (2.56 oz) per gallon of gas. A rich mix would mean more oil.

Both affect combustion. If the mix has too much or too little oil, starting will be affected -- stick with 50:1. (I would suggest leaving the carb mix needle alone for now, if you haven't moved them -- can probably get into added difficulty if you try adjusting.)

Pulling the choke knob closes the choke in the carb, pulling more fuel into the engine on cranking or running. That can flood the engine. Try starting without the choke more often than not. Use the choke sparingly. Think this is consistent with what was said above (flyingscott) -- use more throttle than choke.