F115 vibration

[lunartic]

I have about 5 hours on new Yamaha F115. The motor runs great except that at idle speed(700-800rpm) in gear, I'm getting vibration. As soon as I get to 1000 and above rpm motor runs smooth. The dealer said this is typical during break-in, but is not improving. Any one else experience this? Is it normal? Part of the reason for buying 4 stroke is smooth low end operation. Also, I have not hit anything to put the motor,prop etc out of balance. Thanks

[Bill K]

I did not experience any vibration during my break-in with mine. Suggest you get the dealer to reexamine.

[MDT]

I've twin F115's (model year '00) and they have been smooth from first start up. Comparing against mine, the unit should have minimal but expected side-to-side virbaration at crank and start up. Even with the choke on, they should smooth right out to idle (~700 rpm)with no visible vibration. I don't run with the choke on but if I fail to turn the off at the launch, they will remind me with the smell of rich exhaust.

As a last point of reference, you should be able to stand ~7 ft from the motor (my distance to the helm) and the only visual indicator of operation is the cooling water jet off the starboard side. I have had people walk up to the boat at the dock and ask me to start them up so they can see/hear for themselves how quiet the 4 Stroke is. I simply point at the water jet and smile.

Please keep us posted as to what you find.
Regards,
MDT

[srj]

I have about 12 hours on mine--no vibrations.

[NINER]

I have about 2.5 hours on my f115 and I get a vibration that rattles my depth finder on the dash at idle in gear. No vibration in neutral or with the throttle slightly advanced. I did'nt really think to much of it when I was on the water but next time out I'll do some checking. The book says to check the oil for burn and that thats normal, mine has not burned a drop I hope thats normal. And for general info my 1800 fisherman with 7 people and half a tank of gas was doing 44mph.

[New Motor Guy]

I have the same situation. A small vibration at low rpm's.

[zen]

I had vibration problem too. Had to lock up my center console window at low rpms in order to reduce the noise.

[jigtugger]

The first thing I would do is get a different prop on it. It is very common for stock props to be slightly out of balance. I remember with my F115 last year, when trying different props it would vibrate slightly different with each prop while in gear at idle. Just my 2 cents.

Jigtugger

[1775prov]

My new F115 has about 20 hrs on it and here's what I have noticed about the vibration on my motor. If I come down off plane and roll the throttle back to idle quickly I will "almost always" get a heavy vibration that will continue unless I do the following: I goose the throttle slighlty to about 1200 rpms and come back to idle. The vibration always goes away until it reappears the next time I come down from WOT. Ocasionally I have had the motor vibrate heavily in gear as I'm shifting in and out of neutral/reverse while backtrolling. I do the same deal with the throttle and it stops. My 75 Honda never did this particular little quirk. It's annoying but as long as it doesn't grenade I can live with it.

[Indiana Lou]

Don't take any chances - force the dealer to address the problem. I also have a new 2002 F115 and it runs perfectly on a Lund Pro Sport (also only have 5 hrs running time on it - NO vibrations). If you get any flak from the dealer or if they tell you not to worry but you are still uncomfortable call Yamaha directly. They WILL force the issue until you are satisfied. Remember how much hard-earned after-tax cash you forked over for your engine - you should be VERY happy with it.

I did this recently with my engine. It turned out to be a very minor cable adjustment but it affected performance (couldn't get above 4000 RPM)and the dealer was giving me the runaround. I called Yamaha and if the Dealer hadn't called me back that afternoon, they were prepared to step in themselves. I was quite surprised at the response, and was worried that they would screw my relationship with the dealer, but they told me that unless I told them everything was perfect, they would step in and force the issue. Good for them, and good for me. Luckily the dealer called me back and fixed the problem right away, although to this day I'm not sure if Yamaha called him and gave him a "push" without me knowing. The dealer never mentioned it.

I would also put my concerns in writing if the dealer didn't pay the attention the matter needed. You would be surprised what a written note can accomplish. It can also establish a paper trail if there is a problem later - especially if the dealer tells you not to worry, then I would send him a letter confirming exactly what you were told.

Bottom line is that although you have a warranty for now, that warranty will expire and if there is a problem that gets worse YOU will ultimately be stuck with it unless you force the issue.

Sorry for my long message, and I hope it doesn't sound like a rant, but thats my 2 cents!

[EsoxProSport]

The same topic Vibration at Idle on Merc/Yamaha 115 4 strokes came up about a month ago on this board. If I remember correctly those using a STainless Propeller were getting a Vibration only at idle speeds due to the weight of a Stainless Prop spinning at low RPM. I would swap props and see what happens .. you should always have a spare anyway.

[MDT]

1775prov: Your problem sounds just a little like a throttle position sensor setting. My starboard unit did this but would eventually cut out. If I kept it just out of neutral (when coming back from open throttle), it would be fine. It took two trips to the dealer before he got it right. Once corrected, my unit runs fine... just like the port.

The adjustment is almost a "do-it-yourself" thing except it requires a Test Harness (part 90890-06793). Since you are still under warranty, I would say it is Dealer Time. There is a Yamaha Tech Note out on this from Spring/Summer last year.
Regards,
MDT