[C320-list] Engine noise

[Richard A. Walker]

Ah the noise could be from not burping the shaft seal  This incident occurs
after a diver has cleaner you hull.  Air gets into the shaft are and
displaces the water, thus no water lubrication on the seal.

To "burp" I put a sponge under the coupling then move the spring aft
quickly.  A 1/2 cup of water normally comes in.

Cheers,
 
Dick Walker
C-320 (687) WindWalker II
740 Olive Ave.
Coronado, CA 92118-2136
619.435.8986

-----Original Message-----
From: c320-list-bounces at catalina320.com
[mailto:c320-list-bounces at catalina320.com] On Behalf Of james_delong
Sent: Monday, July 16, 2007 6:27 AM
To: catalina at thehares.com; C320-List
Subject: Re: [C320-list] Engine noise

Jeff, Stan, and Jon,

Thanks for the explanations! I do have a PPS.  For awhile things were really

funky out there, so prop cavitations could have been occurring. After 
unsuccessfully attempting to duplicate the problem at the dock I'd guess my 
approach will be to go on with life and assume all is well!

Jeff...how do I burp the PSS if this happens again?

Thanks to all again!!

Jim

----- Original Message ----- 
From: "Jeffrey Hare" <Catalina at thehares.com>
To: "'C320-List'" <c320-list at catalina320.com>
Sent: Monday, July 16, 2007 9:01 AM
Subject: Re: [C320-list] Engine noise


> Jim,
>
>  If you do have a PSS and notice this sound, go down below and see if the
> PSS is warm, and burp it to see if there's any air in there.  If it has
> plenty of water in it, then it's less likely to chatter.  Without water, 
> it
> can chatter under the right circumstances.
>
>  Another possibility is that a shaft zinc has loosened up and slid down
> against the cutlass.
>
>  Final thing I could think of is that if you have a bronze shaft and the
> alignment is not quite perfect, you could be experiencing shaft whip when
> the right combination of prop loading and RPM are hit.  Worn engine mounts
> would help make this worse.
>
> FYI: As for the RPM, 2900-3000 is really the Yanmar's sweet spot on the
> power curve and as Jon said, can run for days at a time there.  Contrary 
> to
> what seems intuitive, running the engine at lower uses significantly more
> fuel, not less as would be the case for a gas engine.  (From a study 
> looking
> at Diesel-alone vs. diesel-electric efficiency)
>
> -Jeff
>
> -----Original Message-----
> From: c320-list-bounces at catalina320.com
> [mailto:c320-list-bounces at catalina320.com] On Behalf Of Stanley Rogacevicz
> Sent: Monday, July 16, 2007 8:34 AM
> To: C320-List
> Subject: Re: [C320-list] Engine noise
>
> Jim,
>   Again IF you have a PSS I'll just state Jon's post a bit differently - 
> In
> following seas - I sometimes got a horrible sounding vibration from the 
> PSS
> when really trying to make some time surfing the waves relieved by a
> throttle adjustment.
>   Also if you are heading - into - big seas that are sending foam to your
> stern you can sometimes hear a different 'growling' sound as the Prop
> Cavitates - fixed, folding, whatever, PSS or not.
> Stan
>
>>>> <jonvez at comcast.net> 7/16/2007 8:19 AM >>>
> Jim,
>
> Could be cavitation from the prop, which can happen in rough seas or if 
> the
> boat is outrunning the rpms. If you have a PSS, it can chatter when 
> bouncing
> around sometimes. I've had this happen and have done what you did...ease
> back the throttle, make sure everything else is okay and continue....
>
> Regards,
>
> Jon Vez
>
> -------------- Original message --------------
> From: "Jim DeLong" <jdelong3 at neo.rr.com>
>
>> Wondered if anyone else has experienced this engine noise?
>>
>> While in the ocean a couple of days ago, trying to outrun a squall, a
>> crew member cranked up the RPM's to 3000. More that I'm normally
> confortabe with.
>>
>> After 15 minutes or so, the normally smooth engine (Yanmar 27 HP)
>> began to sound like metal grinding. Pulled the RPM's bact to 2200 and all
> was well.
>> Cranked it up again and after 15 minutes it started again. No other
>> symptoms at all. Ran well but just sounded funky. In port yeaterday we
>> started the engine and ran it up to 3000. Could not get it to do it 
>> again.
>>
>> Thought it may be from the transmission or a slipping shaft, but the
>> prop seemed to turn just fine.
>>
>> Anyone experience this one?
>>
>> Thanks,
>> Jim DeLong #453
>>
>>
>
>
>
>
>