20hp johnson help

[FinS]

i have a mid 80's 20hp johnson that i started having issues with

 

1- it takes 10 pulls or more to start what could i do to make it better to like start on the 1st or 2nd pull

ive changed the plugs

 

2- when full throttle the motor always wants to go left so no letting go there or ill be doing doughnuts which aint to safe

 

anyinput on these problems would be great

[lew]

Getting the motor to run straight is an easy fix.

 

Under the skeg and just above the prop, you'll see a small fin that's adjustable to take the torque off your sterring. Just loosen the bolt and turn the fin slightly in the opposite direction the motor is pulling then re-tighten the bold and give it a test drive.

 

Just do it a couple degrees at a time until you get it where you want it.

Edited May 25, 2008 by lew

[Sinker]

What Lew said will get it running straight.

 

Have you ever ran anything thru the motor to de-carbon it? I'd get some seafoam and run it thru the motor. It will clear a lot of the carbon build up out, and make it run smoother. Should help with the hard to start problem. Mercury power tuner does the same thing, and I find it easier to get. Just be prepared for a ton of smoke when you do it. If you've never de-carbed it before, she'll be smoking like 90!!

 

Sinker

[FinS]

thanks for the info guys

Edited May 25, 2008 by FinS

[2 tone z71]

Tuner will definatly help pull the plugs check compression,then go thru the carbs thats what it sounds like to me a fuel issue

[boatman]

I don't think you will find the fin Lew mentioned on a mid 1980's Johnson 20 hp. You need to tighten the steering. Should be a bolt or screw in the round steering tube of the midsection. Unfortunately, I'm away from home so I don't have access to my mid 1980's Johnson's or service manuals tom tell you exactly where it is. If the engine runs ok once its started then you have either border line compression or a fuel issue. 10 pulls suggests a fuel issue. You probably need to rebuild the carb. When was it last running well?

[glen]

I put a new fuel hose on my old motor and she ran good after that. After 20 or 30 years its good to get a new hose.