Late last summer, I bought a 2009 Glastron GT 205 with a Volvo Penta 5.0 GL-J, an SX-A drive (1.60 gear ratio) and a Turbo 4-blade prop. It has about 185 hours on it. When it is in gear -- whether running on the hose or in the water, idle or faster RPMs -- it makes a whine loud enough to be heard from the cockpit over the engine noise. I noticed this on the test drive but didn't think too much about it at the time. Before I bought it, I had the boat inspected (including lake test) by the dealer who originally sold it, and they didn't comment on it (in hind sight, I should have asked about it). I am wondering if this is normal or a problem and, if it is a problem, how serious could it be?
A very similar noise can be heard in this YouTube used boat sales ad (2007 model of same boat and engine). The noise is audible much of the time between around 1:40 - 2:30 in the video.
YouTube video (listen from about 1:40).
The noise was a topic of discussion on this forum over 10 years ago, where it was attributed to a new design using straight cut gears, and a problem that VP was looking into (iBoats Forum thread). If VP was actually looking into it, I'm surprised that I haven't been able to find any evidence of a conclusion to their investigation.
On a 2017 discussion on a Chaparral Boats forum, people suggested bad gear alignment, a bad bearing, and one person said it led to a drive blowing up (Chaparral Boats Forum thread).
Surprisingly, other than speculations and anecdotes, I can't find any definitive conclusion about the source and prognosis of the noise. Should I be concerned or is this normal for these drives? Is there something I need to do?
I changed out the gear lube last fall when I winterized it and it looked brand new and clear. The magnet on the plug was clean. I refilled it with Volvo Penta synthetic 75W-90 GL-5 gear oil, and the level was in the middle of the acceptable range after running it in gear on my driveway this spring. As far as I can tell, the service didn't change the noise. I have not yet removed the drive to inspect and check alignment, so if there is anything specific I should check related to this noise, advice would be appreciated.
A very similar noise can be heard in this YouTube used boat sales ad (2007 model of same boat and engine). The noise is audible much of the time between around 1:40 - 2:30 in the video.
YouTube video (listen from about 1:40).
The noise was a topic of discussion on this forum over 10 years ago, where it was attributed to a new design using straight cut gears, and a problem that VP was looking into (iBoats Forum thread). If VP was actually looking into it, I'm surprised that I haven't been able to find any evidence of a conclusion to their investigation.
On a 2017 discussion on a Chaparral Boats forum, people suggested bad gear alignment, a bad bearing, and one person said it led to a drive blowing up (Chaparral Boats Forum thread).
Surprisingly, other than speculations and anecdotes, I can't find any definitive conclusion about the source and prognosis of the noise. Should I be concerned or is this normal for these drives? Is there something I need to do?
I changed out the gear lube last fall when I winterized it and it looked brand new and clear. The magnet on the plug was clean. I refilled it with Volvo Penta synthetic 75W-90 GL-5 gear oil, and the level was in the middle of the acceptable range after running it in gear on my driveway this spring. As far as I can tell, the service didn't change the noise. I have not yet removed the drive to inspect and check alignment, so if there is anything specific I should check related to this noise, advice would be appreciated.