[C320-list] Running engine with seacock off?

[Bob Borelli]

I overheated M30 on October 10, 2019 apparently due to 6 vang raw water impeller failure after 8.0 engine hours.
Pulled exhaust elbow to look for carbon deposit in elbow & heat exchanger.
Also to determine if add 'hump hose' to the exhaust hose.
All appeared well.
Except interior layer of exhaust hose apparent exfoliation, a bubble in the inner wall of the exhaust hose.

Fix?  New exhaust hose at a later date.
Visually inspect impeller housing & shaft for damage ie. scoring, play.  None.
And new 8 vang impeller smeared with silicone grease.
And install Borel raw water alarm with sensor on exhaust hose just south of elbow.

On June 15, 2020 or 11 engine hours later,
Suddenly M30 overheat due to closed raw water sea valve.
Stupid!  Did not open sea valve!   Did not follow written procedure for starting diesel!

OK, check raw water impeller - blades OK.
Than operate M30 at various rpms - OK.
Apparent water volume expelled from overboard discharge - OK.

As of today, 15  M30 engine hours ago and all is well.
M30 running like a charm.
No apparent damage to over heat due to operate M30 with raw water valve closed.

Gosh I love this boat!

Bob Borelli
1995 C320  'Elusive'  1994 Perkins M30 diesel
Mooring no. 10 Sailing Associates Inc.  Sassafras River, Georgetown MD
(415) 530-6137
________________________________
From: C320-list <c320-list-bounces at lists.catalina320.com> on behalf of Allan Field <allanfield47 at gmail.com>
Sent: Monday, August 3, 2020 5:54 PM
To: C320-List at catalina320.com <C320-List at catalina320.com>
Subject: Re: [C320-list] Running engine with seacock off?

Wherever I have the engine seacock closed, I leave the engine key next to
the seacock. Great memory aid!

Allan S. Field
Sea Shadow - C387, #103 (formerly C320, #808)
Columbia, MD

On Mon, Aug 3, 2020 at 4:20 PM Michael Ferguson <coralman at bellsouth.net>
wrote:

> I would check the raw water impeller blades. MichaelNauti Clew 169
>
> Sent from AT&T Yahoo Mail on Android
>
>   On Mon, Aug 3, 2020 at 3:19 PM, Graeme Clark<cg at skyflyer.co.uk> wrote:
>  Oops
> Finally did it
> Started the engine and let it idle for a few minutes then slipped my lines
> and gently motored off
> Suddenly realised I hadn’t turned on the seawater cooling seacock
> Turned it on. Water coming out of exhaust. No external signs of damage to
> exhaust hose or water muffler
> But will there be internal damage?
> Am I risking sudden hose rupture for example?
> As I recall it’s nigh on impossible to remove hoses without damaging them
> Ideas?
> Graeme
> #366
> 1996
> Falmouth
> England
>
> Sent from my phone. Excuse typos!
>