1957 Evinrude 18 hp Fastwin Electric 18

[tmise]

Took boat out for the first time yesterday using this 18hp as the trolling motor. All in all it ran pretty good but was vibrating so much that the high speed valve unscrewed itself and fell out!! Luckily it fell in the boat and not in the water. The carb was rebuilt and new packing washers were installed that i thought would prevent the valve from loosening up like that. Any ideas as to why it would be vibrating so much?

 

[HighTrim]

Re: 1957 Evinrude 18 hp Fastwin Electric 18

How is the prop? Any damage to the blades? No missing shock absorbers?

It should never vibrate loose. I would add more packing, then once you adjust the needle tighten her down. Always keep a 7/16" wrench on board for this.

 

[scottmm73]

Re: 1957 Evinrude 18 hp Fastwin Electric 18

I don't know if the 57 has motor mounts (vibration isolators), if it does, what is their condition? Was it vibrating at all RPMs? Prop damage, crank damage? It really could be a number of things.

 

[kfa4303]

Re: 1957 Evinrude 18 hp Fastwin Electric 18

These old 18-20hp motors should run pretty dang smooth. Are you sure you were running on both cylinders? Dropping a cylinder could cause the motor to run tough and vibrate excessively. Here are some links to vids of other 18-20 in action to give you an idea of what to expect. Otherwise, I would go with High Trim and add and extra piece of packing and tighten down the nut. I keep also keep a 7/16" and large flathead screwdriver on the boat at all times. You can practically rebuild the entire motor with those two tools.

1958 Johnson 18 HP outboard - Running - YouTube (nice idling 18 hp. Although it should be a couple inches deeper in the water for good measure)
Johnson 18 hp 1963 - YouTube ( an 18hp running WOT)
Maintaining Johnson E & FD Serie (great all around maintenance link)