Johnson specialty tool.

[misery]

I'm in the process of rebuilding my 1986 johnson 150 hp after a serious overheating and i have run across a few things in my manual that have my worried. My motor has precision ground connecting rods and my manual says that i need a special tool to properly align the rod end caps. Is this absolutely necessary or can it be done by "feel"? I am not new to internal combustion engine internals, just big v6 boat motors. If the tool is essential does anyone know where i could buy such a tool?

 

[Faztbullet]

Re: Johnson specialty tool.

If the tool is essential

No.....Just mark em..

 

[misery]

Re: Johnson specialty tool.

Thanks for the quick response faztbullet. I'm hoping to have this motor ready for the spring. the snowmobiling sucks up here right now and the boating is even worse, so i figured i might as well try to save this motor.

 

[boobie]

Re: Johnson specialty tool.

You can also use a good sharp lead pencil to align the caps when tightening. Yes I know these are precision ground rods and you should use the tool and the pencil was for the sanded rods but I have used the pencil in a pinch.

 

[Haffiman]

Re: Johnson specialty tool.

The big ends of the rods are 'cracked', and mating the surfaces are important. Important that the surfaces are 100% clean and oil and dust free. You may however do without the special alignment tool if careful. Go by 'feel', I sometimes just used my finger nail. If 'shaving' the nail, re-align or use a soft pencil as mentioned above.

 

[boobie]

Re: Johnson specialty tool.

Forgot. You could also use a dental or floss pick to make sure the rod caps are aligned.

 

[angler00]

Re: Johnson specialty tool.

what made it over heat?? I also have a johnson 150 is there something I should be looking for??

 

[daselbee]

Re: Johnson specialty tool.

Do a dry run on aligning the caps on the bench. Try one first. Get the hang of it.
Do not torque the cap down unless it is PERFECTLY aligned with the microgrooves that are created when the rod is cracked.
It is like a piece of china that is broken, the pieces will fit together one way only, but when aligned, almost
imperceptable that there is a crack there.