07-06-2017 06:13 - edited 07-06-2017 06:14
Because your 17" aluminum turns 5400 rpm, a 17" Rogue ( 763966 ) should put the rpm closer to 5000-5200 rpm which is an ideal and optimal range for your 90 HP. It should also pick up a bit of speed and accelerate better. Keep in mind that propping is always trial and error.
My 2014 90 HO does the exact same thing.. I showed a local dealer a video, the mechanic said i should bring it in.
I brought it in because they said I could have it back by the following weekend... They drained the oil, It was clean, no shavings. They could hear the rattle/chatter while in gear at idle rpm. They contacted BRP, BRP suggested changing the prop from the Aluminum to a Stainless. They installed a viper and they said the rattle went away. They said the rattle/chatter is not doing any damage, it is due to my boat and motor combination, they said the boat is light. They said that the stainless prop has less flex and it is heavier which engages the gears better.. They did not recommend me buying a stainless prop because of my lake, they said if i hit something it will damage the lower end.
I got stuck with a $300 bill, that I wasn't happy about, even though I have warranty till 2021. They said it was because they found nothing wrong... They are the only guy in town, so I ate the $300 this time.......
When I start off from a cold start, no noise. Go for a 15 min ride, come down to idle speed...It rattle/chatters, Turn the boat off and restart, put into gear at idle speed....NO rattle/chatter.... This noise pisses me off, besides changing the prop, is there nothing else that could be done?
I also tied the boat to our dock, put it in gear, it would rattle till the ropes got tight and there was load on it. Then the rattle went away.. So it seem like it is a load issue or lack of it?
Here is a video link to my issue
07-31-2017 06:39 - edited 07-31-2017 06:41
All makes of outboards can rattle at idle due to the gear lash between the teeth and the propshaft moving in and out slightly. It all depends on a number of variables.
Most often we find it minimized with a change of propeller. Occasionally a prop my have a blade slghtly "out of true" which accentuates the propshaft moving in and out while rotating in gear due to the uneven thrust of the affected blade.
Sometimes a 4 blade prop eliminates the problem.
In your case, perhaps increasing the idle rpm slightly may alleviate the problem. That puts more load on the shaft to minimize movement. See your dealer as the diagnostic software is needed unless your motor has the push button idle speed adjustment.
It may be beneficial to write an email to firstname.lastname@example.org with your serial number, dealer name, and a short history of your engine. No promises, but they will investigate the situation.
2 weeks ago - last edited a week ago
Hey Peanut I stumbled across your Youtube video when I search "Etec lower unit rattle" I have a brand new (2017) 90HO that does the same exact thing!!! It drives me crazy!
Here's the link to a thread I started desribing the same thing and looking for answers..
Have you (or anyone else) found a solution to this???