raychamber2
Recruit
- Joined
- Jun 22, 2004
- Messages
- 3
My 1961 johnson 40hp starts great and will run<br />forever in a barrel. However, in the water under<br />load she heats up to the point of shutting down.<br /> I have changed impeller and thermostat, and now<br />am in the prosess of having the head checked and<br />head gasket replaced. Any other suggestions would be appreciated. I sure would like to get back into<br />the water with no problems and enjoy a day of<br />boating.
<br /><br />What mix are you using? Your engine calls for 24:1. Using 50:1 can cause overheat.<br /><br />What plugs are you running? Should be Champion J4C (used to be J4J) gapped at .030". Wrong plugs can cause it to run hot.<br /><br />Has the link 'n' synch been verified? Too much ignition advance can also cause hot running.<br /><br />Finally, too much prop pitch for the boat you have it on can also cause overheat.<br /><br />I will move this to Johnson Troubles.<br /><br />Good luck, and let us know what you find.