I have a new boat with a minnkota autopilot on the front and it vibrates the whole boat when it is wide open. It is not the prop, looks brand new. Any ideas?

If you're absolutely sure the prop is perfect, I'd take a stab and say the prop shaft is bent out of round. If you have a dial indicator, take the prop off the shaft and put the dial on the shaft.

Total indicted runout of any shaft shouldn't be more than .002. Granted, if it's a little more it shouldn't be that big of a deal. If it's, say, .010 then you have a problem.

thanks boiler, I will try that!

If you don't have a dial indicator, most auto parts stores have them. Doing a TIR on a shaft takes like 7 seconds. They should be able to do it right at the counter.

When you say it's a new boat... does that mean it's a brand new trolling motor as well?

If you've got everything bolted down tightly it's time to check into the warranty on the trolling motor in my opinion.

You can narrow the issue down per boilerguy's info above, but if it's under warranty that's about as far as I'd go.

marine_man

One other thing to check is pull the prop off the trolling motor. Where the pin goes through the shaft the prop fits over that in a channel. If the prop, which is plastic is slightly off where the pin sits in it won't be perpendicular to the shaft. Its a matter of slightly shimming that channel on the low side of the prop where the pin sits to get the vibration to go away. I've had to do that to a couple of props. Good luck.

I had a similar issue when I bought mine. The prop looked straight as an arrow when spinning out of water, shook entire boat when trolling. New prop fixed it. Just something to try down the road if nothign else works.