Johnson 6HP 1974 wont run under 3/4 throttle

[boat boys]

I have just purchased a Johnson 6 hp (white) I thought by the serial number it was about 1985 but it has points?

it was not running when I got it, so I cleaned the carby and adjusted the points, but it is only just running, it starts fairly well at max reves, adn will build up to run at high revs but as soon as i try to throttle it back, it cuts out.

I have been through this forun, which has always been a great help to me, but dont seem to be able to find a similar problem.

I have adjusted the points to 20 though which seemed to help (they were about 13.

• the compression is 65 psi on both cylenders.
• the tow coils have bad cracking in the covers.
• the outboard seems to run really rich, lots of smoke and oil in the water.
• I have not replaced any electrics or the plugs (Champion J6C)
  
  I would really appreciat any sugestion, I am really lost

 

[bktheking]

Re: Johnson 6HP 1974 wont run under 3/4 throttle

If the coils are cracked start by replacing them. I wouldn't try and troubleshoot anything until they are done, it may correct the problem.

 

[boat boys]

Re: Johnson 6HP 1974 wont run under 3/4 throttle

Thank you king, I will order two coils, and hopefully have them by the weekend, I didnt want to just start replacing stuff when I had no idea what the problem might be.

 

[boat boys]

Re: Johnson 6HP 1974 wont run under 3/4 throttle

Hi again,

I have received the new coils and are just putting them in.

I notice that the armature plate has a little play in it, is this supposed to be form? or can it have a little play?

thanks

 

[boat boys]

Re: Johnson 6HP 1974 wont run under 3/4 throttle

Thank you for your assistance.

to close off this thread for others with th same problem, the coils were the problem.

I replaced both cracked coils with a pair of second hand ones and it was away.

the armature plate is still a bit wobbly, but the outboard seems to run OK. I guess that will be my next job some time.

hope you all had a great Christmas