V-Drive Question

What are these trans. supposed to sound like, and what is a bad sound? I am not very familiar with v-drive boats, and was looking for a little insight. I have driven a couple boats now, and they all have made a little noise, but they have all sounded a little different. Is reverse always noisy?

Any thoughts would be appreciated.

Thanks,

Darin

reverse is always noisy, they do make a little noise.

Typically reverse gears have half as many teeth as the forward gearing. This is true both in car and boat transmissions. This is usually the cause of noise while in reverse.

Every transmission that I have ever rebuilt, both manual, automatic and marine type has a similar number teeth per gear for forward and reverse depending on gearing ratio. Forward and reverse is generally just controlled by a set of planetary gears which reverse the direction of the main shaft which in turn make the extra noise. The synchro looks look a gear and has minimal teeth, is that what you are talking about? In PCM powershift plus transmission forward and reverse are identical.

(Message edited by san210Nut on October 23, 2006)

It's the way the gears are cut that makes the noise (on purpose). I would guess (though I have never been told officially) that this is to remind the driver that the boat is in reverse.

It's the planetary gears!

I just noticed that in forward, at idle speed, right at a certain rpm, it has a little whine sound to it. As soon as the rpm increases a tiny bit, it is gone. After that it sounds very normal.

Hurth now recommends motor oil in the tranny instead of tranny fluid to cut down on the noise.