[C320-list] New Boat knocking noise

[Dave Rabinowitz]

If the alignment has been checked, then perhaps the problem lies elsewhere?
Any thought to the engine having an issue?  The problem exists at any rpm
above 2300, not just at 2300 rpm.

Maybe a cylinder is missing (mis-firing, I'm sure you'd notice a missing
cylinder! sorry, I know an issue like this isn't funny), an injector is
flaky, fuel pump/fuel flow, etc.  What engine do you have? Maybe someone
here is familiar with it.

The boat's pretty neat and lots of fun.   Too bad you have to go thru the
trials/commissioning issues.

Good luck! let us know how it turns out....

dave
Wind Chill
#445





On Sat, Jun 21, 2008 at 10:22 AM, John Frost <john at frostnet.net> wrote:

> Jerry
>
> For what it is worth, our hull (19 before yours 3 blade fixed prop) has a
> "mild" vibration at about that speed. I assume (hope?) that it is because
> the shaft was aligned before the boat was rigged or put in the water. An
> absolute no-no from what I've read. I plan to align in water as soon as I
> can.
>
> Your description below ("The standard prop was then installed, the engine
> again realigned and the boat put back in the water") indicates that you may
> have the same problem.
>
> When you finally do get it fixed, you will love the boat
>
> John Frost
> 2007 C320 MKII, Hull # 1118
> Lake Guntesville, AL
>
> -----Original Message-----
> From: c320-list-bounces at lists.catalina320.com
> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Jerry Brown
> Sent: Saturday, June 21, 2008 6:29 AM
> To: C320-List at Catalina320.com
> Subject: [C320-list] New Boat knocking noise
>
> Suggestions Please
>
> Our new 320 is sitting at the dealer.  From the day of commissioning there
> has been a loud knocking sound from the stern whenever the boat is motored
> over about 2300 revs - we were told it would "settle down".  In two hours
> of
>
> motoring from the dealer premises to our club the engine moved on the
> mounts
>
> sufficiently that it jammed the engine cover which was free when we left (I
> checked the oil before leaving).
>
> Initially the dealer "blamed" the Kiwi Prop that I supplied, and he
> installed.  He realigned the engine and told me to take the prop off and
> reinstall the standard two blader.  While still tied to the dock we tried
> the realigned engine (still fitted with the Kiwi Prop) as I was reluctant
> to
>
> move the boat for fear of doing more damage.  The dealer also dove under
> the
>
> boat to check that the prop was not fouled and that the blades were free.
> In that test the engine was moving around sufficiently to open up the
> stuffing box under load.  The dealer then thought that the initial motoring
> and engine movement might have bent the propshaft.  The dealer then
> arranged
>
> to have the boat moved (with minimal motoring) back to his premises.  The
> Kiwi Prop was removed and the shaft and coupling sent to a machine shop for
> checking.  With the boat out of the water it was clear that the shaft was
> not aligned.
>
> The machine shop confirmed that the shaft and coupling are true.  The
> standard prop was then installed, the engine again realigned (the mechanic
> is getting lots of practice) and the boat put back in the water with
> assurances that all would now be good.  The opposite is true.  At 2300 revs
> the noise is more persistent and louder than with the Kiwi Prop.  A
> subsequent test by the mechanics with the engine covers off lead them to
> say
>
> that, at the point where the noise starts, the motor can be seen to "move"
> sideways visually.  Another symptom is that when the engine is throttled
> back,  a relatively low frequency vibration passes through the hull which
> can be easily felt at the wheel.  The boat almost seems to be "shaking it's
> hips"  There are no abnormal engine noises etc, no black smoke or any other
> signs of engine problems.  It is smooth at idle and when revved in neutral.
>
> Having confirmed that this is not a Kiwi Prop problem (i.e. my problem from
> the dealers perspective) the dealers' next suggestion is that possibly the
> wrong engine mounting rubber blocks were installed from new.  That seems a
> possibility, but a pretty remote one.  I would welcome other theories as
> our
>
> season is rapidly disappearing.
>
> Jerry Brown
> #1137 Indigo
> ----- Original Message -----
> From: <bruceheyman at cox.net>
> To: <C320-List at Catalina320.com>
> Sent: Saturday, June 21, 2008 2:40 AM
> Subject: Re: [C320-list] PHRF Racing Sails etc
>
>
> > Rick,
> > Our Sailmaker modified the pockets so that we can go with either full or
> > partial battens.  So far our favorite configuration is full for the top
> > two and partial for the bottom two.
> > Best,
> > Bruce
> > Somerset 671 SoCal
> > Sent via BlackBerry by AT&T
> >
> > -----Original Message-----
> > From: "Rick Evans" <ericstillwellevans at gmail.com>
> >
> > Date: Sat, 21 Jun 2008 02:46:26
> > To:C320-List at Catalina320.com
> > Subject: Re: [C320-list] PHRF Racing Sails etc
> >
> >
> > Thanks Bruce I was really curios on whether the dutchman would work loose
> > footed.
> >
> > I'm glad it will.
> > Sent via BlackBerry from T-Mobile
> >
> > -----Original Message-----
> > From: bruceheyman at cox.net
> >
> > Date: Sat, 21 Jun 2008 05:14:41
> > To:C320-List at Catalina320.com
> > Subject: Re: [C320-list] PHRF Racing Sails etc
> >
> >
> > Rick,
> > We have a loose footed main and use the dutchman system with no problems.
> > We like the loose footed main as it seems easier to trim the lower third
> > of the sail.
> > Bruce
> > Somerset 671 SoCal
> > Sent via BlackBerry by AT&T
> >
> > -----Original Message-----
> > From: "Rick Evans" <ericstillwellevans at gmail.com>
> >
> > Date: Fri, 20 Jun 2008 21:17:36
> > To:C320-List at catalina320.com <To%3AC320-List at catalina320.com>
> > Subject: [C320-list] PHRF Racing Sails etc
> >
> >
> > I just started PHRF racing my c320 in Western Long Island sound. I was
> > wondering if anyone can give me some advise on cruising/racing sails they
> > may have upgraded to?
> >
> > I got some quotes from doyle but I am unsure what to go with.  My main
> > questions have to do with the main
> >
> > 1. Loose footed or not?
> > 2. Full battens or not?
> >
> > I love and want to keep the dutchman and want to know if anyone has used
> > it
> > on a loose footed main
> >
>
>