Any clunking would be play somewhere in the drive train. Most transmissions
do not 'engage' or disengage gears, the gears are always engaged and another
device connects or disconnects the gears from the shafts. In your case a
fluid operated clutch. Usually these clutches weaken and slip with age.
Rarely a malfunction can cause the fluid pressure to be too high or the
clutch to grab but that is very unusual. The application of power to the
rest of the drive train will take up slack anywhere there is some. Some
slack is normal but it would not hurt to take a closer look at all the
pieces of the drive train from the engine through to the prop. A u-joint,
loose prop, loose engine coupler, will make a clunk. It is hard to check
the transmission it's self for play because it will not engage unless it has
power to it. The rest of the drive train you can often check with the
engine off by grabbing stuff and trying to turn it against it's self.

"Charles T. Low" wrote in message
. ..
I've had my 1978 Trojan 26 for three seasons now, and can't for the life
of
me decide for sure whether the transmission has always done this or not.
My
mechanic thinks it's OK. The AT lubricant is full and looks crystal clear
to
the naked eye, and I do change it (rarely). It's a Borg-Warner Velvet
Drive,
original with the boat, to my knowledge.

When put into gear, there is a slight pause, a fraction of a second only,
but easily visible that the prop tranny/shaft does not start turning
immediately - then it catches and away it goes. (Idling just above 600 rpm
indicated.) It does so with a very soft audible clunk, and I seem to
remember it being noiseless when "new" (to me).

I have shifted it into gear at above idle speed, very infrequently, count
on
one hand, etc., because I'm kind of clumsy. Other than that, I can't think
of anything that might be considered abusive.

It is still so much smoother than the Bravo II I/O I used to own, which
itself was so much smoother than the Alpha 1 before that. Passengers have
never noticed or commented - it's quite a subtle clunk. I think I may just
be listening too hard.

What is normal behaviour for these transmissions? Thanks.

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Charles T. Low
- remove "UN"
www.boatdocking.com/BDPhoto.html - Photo Contest
www.boatdocking.com
www.ctlow.ca/Trojan26 - my boat

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