1982 johnson 150 no power

[realtorman]

We have a 1982 Johnson 150 model#j150txcnm. runs fine with water hose hooked up. When you put it in the water runs and idles ok, but no power even at WOT boat is bogging down will not pick up speed and never planes out had water in gas cleaned out old gas put in fresh fuel and same problem. Do carbs need rebuilding, or should I look someplace else.

 

[Daviet]

Re: 1982 johnson 150 no power

If you had water in the gas and it got into the carbs they might need to be looked at. Has this engine been setting for a period of time?

 

[HighTrim]

Re: 1982 johnson 150 no power

You likely do not have spark on all 6 cylinders. Idle the boat in water and use an inductive timing light if available to determine spark on each spark plug wire. It always seems to run good on muffs with no backpressure on the exhaust, then on the water the weak/no spark problem rears its ugly head.

 

[realtorman]

Re: 1982 johnson 150 no power

It had been setting for about a year maybe a little longer. also the plugs that are in it have no way to gap them the electrod is in the middle of the plug recessed a little in the middle, haven't seen anything like them before, they are a champion plugs

 

[jonesg]

Re: 1982 johnson 150 no power

drain the carb bowls, big flat brass screw at the bottom of the bowl.
I agree with no spark, classic sign.

Read the faq files for spark test.
http://forums.iboats.com/showthread.php?t=299680
You cannot perform the spark test with a sparkplug, gap has to be almost half an inch. You might as well get the factory manual too.
www.outboardbooks.com

 

[HighTrim]

Re: 1982 johnson 150 no power

Do you have an inductive timing light or simply an inline spark tester with adjustable gap? You will need to determine if you are sparking on all cylinders.

The plugs you are referring to are surface gap plugs. You should either run Champion L16V or UL77V plugs in that motor.

 

[realtorman]

Re: 1982 johnson 150 no power

I do have an inductive timing gun, I assume you check it like a car, by checking each spark plug wire and aming the light where you would check the timing, never done it on a outboard motor. Can you get to the bowl drain plugs with out taking them off its real tight under there.
Thinks for all your help

 

[DKennimer]

Re: 1982 johnson 150 no power

I had the same issue, changed the plugs and that was it, runs great now!

 

[jonesg]

Re: 1982 johnson 150 no power

I do have an inductive timing gun, I assume you check it like a car, by checking each spark plug wire and aming the light where you would check the timing, never done it on a outboard motor. Can you get to the bowl drain plugs with out taking them off its real tight under there.
Thinks for all your help

jeez, go and look.!