[C320-list] Transmission Drive Flange Bolts Fall Out

[Jeff Hare]

I thought so too, but I think the ones that are wired are the square head set bolts that hold the shaft, not the ones that connect the flanges together.
-Jeff

-----Original Message-----
From: C320-list [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Chris Burti
Sent: Friday, August 14, 2015 12:59 PM
To: 320 <C320-List at catalina320.com>
Subject: Re: [C320-list] Transmission Drive Flange Bolts Fall Out

I'm going from memory, but aren't those bolts drilled for safety wire?

On Mon, Aug 10, 2015 at 1:24 PM, Ken Geiger <kendgb at aol.com> wrote:

>
>
> Northern Dream,  hull #765 is a 2000 year build with a Yanmar 3GM30F 
> engine s/n E25479 with Marine Trans (from an old Survey) .
>
> Trans S/N and other info not known but I can update that when next aboard.
>
> I have pictures of the nuts and bolts for those interested.
>
> Ken
>
>
>
>
>
>
>
>
>
> ---- Original Message ----
> From: Chris Burti <clburti at gmail.com>
> To: 320 <C320-List at catalina320.com>
> Sent: Mon, Aug 10, 2015 12:38 pm
> Subject: Re: [C320-list] Transmission Drive Flange Bolts Fall Out
>
>
> Ken,
> Engine, transmission and Hull Number info would be helpful...please 
> share.
>
> Thanks,
> Chris Burti,
> Commitment, #867
> Farmville, NC
>
> On Mon, Aug
> 10, 2015 at 9:51 AM, Ken Geiger <kendgb at aol.com> wrote:
>
> > A few days ago
> while motor sailing we heard a low vibration sound.  While
> > continuing, I
> inspected the transmission output area and at first saw
> > nothing shaking but
> then observed 2 bolts laying on the floor under the
> > drive flange.
> >
> > We
> stopped the motor and I found 3 of the 4 bolts had fallen out and the
> > fourth
> bolt was loose with the nut still attached.  I found all the nuts
> > bolts and
> washers under the engine and replaced them and got back under way.
> >
> > Later
> at anchor I removed each bolt and nut, cleaned and re tightened with
> > some
> blue loc tite that we had on board.
> >
> > The 4 bolts were M10- 1.25 x 33 mm
> long except 1 was 35 mm long. The bolt
> > used a 15 mm wrench and the thin nut
> used a 17 mm wrench.  The bolt head
> > had a #7 forged on it.  There was a lock
> washer used but placed under the
> > bolt head. On auto applications these nuts
> and bolts would be high strength
> > and perhaps these are as well.
> >
> > I
> intend to investigate replacing the above coarse thread with M10-1.0
> > fine
> thread bolts that will be more resistant to loosening; fine thread
> > bolts are
> used on auto drive shaft flange applications.
> >
> > There is limited space
> between the back of the transmission flange and the
> > transmission but I will
> also investigate using a nylock self locking nuts
> > there.  There is also
> limited wrenching space between the bolt heads and
> > the driven flange that may
> present problems finding a suitable bolt.
> > Perhaps this is why the bolt head
> is 15mm across the flats.
> >
> > I also will had a look at the motor mounts and
> cutlas bearing as the prime
> > source of the vibration that loosen the
> bolts.
> >
> > A quick search of this forum found no similar discussion.
> >
> >
> Comments welcomed.
> >
> > Regards
> >
> > Ken Geiger
> > Northern Dream #765
> > on
> Georgian Bay
> >
> >
> >
> >
>
>
> --
> Chris Burti
> Farmville, NC
>
>
>


--
Chris Burti
Farmville, NC