Yamaha vibration at idle only

Driving me nuts, anyone else know what this could be ?

Go to neutral and it doesn’t rattle or vibrate at all.

Put in gear at slowest speed possible and it rattles terrible.

Put your hand in the cowling or steering linkage on front side of motor and it stops.

The vibration is definitely coming from the motor and not the net or aluminum pan you see in the video.

Warranty is up next month.

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1. 964F355A-E147-445B-A392-5DBE6AA2AC2B.mov

Father in laws out board had to attach a bungee cord to the metal steering rod while driving or rattled like crazy.

I would guess the prop,that 70 should be smooth as silk! something is not right hands down,we sold a ton of those 70’s and they are smooth! try different prop if you can,then start fuel water seperator filter if you have one.

Thanks.

I did just have the prop redone by Soderbloom’s. Had very little edge chips on blade, so I sent it in for repair over the winter. Looked great but that’s the only change to the boat and now this vibration.

I changed the fuel water separator with my last service before I stored it for winter.

I’ll buy a new prop to start with.

perfect, get new prop,keep repaired one for a back up!

I just ordered the exact same prop that I’ve been running since the boat was new. Hopefully that is the problem.

Are you sure the motor isn’t missing on one cylinder? Try changing the spark plugs.

Didn’t do it even once yesterday when I had it out? Prop will be here Saturday

If it didn’t do it yesterday a new prop isn’t going to make a difference.

I have a Yamaha 115 that does exactly this when going from neutral to forward. If I advance throttle slightly and then return to idle, the vibration goes away. I’m thinking it is the shift cable adjustment.

I looked at the linkage and found a video saying the two scribe lines, one on cam and the other on bracket should align at neutral. My cam was set forward about 3/8″, so I adjusted it back to align it. Tried it with the cups and hose and it seems it may be improved. Will know next time at lake.

Hate to mention this but…….do you have the VTS idle option? Could it be the rpm’s are really turned down?

I had a 50 Yamaha that would impart some vibration to the boat when trolling at idle. It was happening when the trim was all the way down and wold go away when I bumped the trim up a little.