Reply To: 1975 Johnson 15R75C 15 hp

[Buccaneer]

I had checked this engine for spark prior, and it seem to be good.
I didn’t have any correct spark plugs, but ordered some.
Put them in today, and it appears that it’s going to “wind up”.
Amazing that it idled as good as it did before on one cylinder.
Motor is now on the boat, and awaiting a test run tomorrow.

I adjusted the low speed needle initial setting to 7/8 turn as suggested, but
think I now have it around 1/2 turn open. Will see where it
ends up after running it on the lake.

This 1975 has no thermostat, and the tell-tale pumps water
as soon as it starts. I’m guessing the later models with thermostats
didn’t foul spark plugs as bad?

After the video, I ran it again with the tank down lower on a stool,
and it seem to run okay with no fuel problems, with the cap loose,
and tight.

How are the caps on these plastic gas tanks suppose to vent or relieve
pressure? The tank was sitting in the sun prior to running the motor,
and appeared to be “bulging”. I cracked the cap and it had a lot of built
up pressure. I see no vent hole in the cap. How do they work????

VIDEO———–
https://youtu.be/5nxe_TBTGQY

Prepare to be boarded!