[64'Cherokee]

I have a 64' Evinrude 40hp outboard. Ran great all summer. It developed a problem late in the summer when running at full throttle. Half throttle runs smooth, push it to full throttle, and it appears to pop out of gear. When you throttle down half way, it runs fine again. I did check the seals in the lower unit, they're ok. Haven't looked at anything else yet. Suggestions on where I should start ?

[JB]

Evinrude Troubles/Repair topic

[Paul Moir]

In '64 the 40hp was available with electric shift and with manual. Which do you have?Either way, check the propeller to make sure the rubber hub in it is not slipping. You can sometimes check this if it's really bad on the mechanical shift engines. Pull the plug wires off, put the engine in gear (you may have to rotate the propeller a bit while doing this) and have an assistant hold the flywheel. You try to turn the propeller with gloved hands. It should twist a bit but it should spring back.A more conclusive test is an on-the-water test. Take the black nose cone off the prop shaft and make a mark on the outer part of the prop - the part with the blades attached - that lines up with the drive pin. Replace the cone, take the engine out for a spin, and check to see if the mark still lines up with the drive pin.