[C320-list] Perkins Perama M30 Overheating

[Mark Cole]

After talking to an engine mechanic, I leaning towards failed heat exchanger.  That would explain the antifreeze in the bilge while the heat exchanger is still full.  Has anyone replaced their heat exchanger?

Mark
Fiddler’s Green #8
Tacoma, Washington

> On Aug 26, 2017, at 11:44 AM, Scott Lagerquist <lgrqst at aol.com> wrote:
> 
> For overheating problems that are intermittent there is likely a problem with the raw water flow.  Check the strainer, then the impeller and housing of the raw water pump, then the mixing elbow of the exhaust system.  Perhaps an acid treatment through a raw water system would eliminate or reduce a blockage in the mixing elbow.  Has anyone treated the Perkins M-30 with an acid/water mixture?  I'd be interested in the process and results.  
> 
> Scott Lagerquist
> 1994 320, #39
> Sea Esta
> San Diego CA
> 
> Sent from my iPad
> 
>> On Aug 26, 2017, at 6:18 AM, Timothy Woods <woodstimothya at gmail.com> wrote:
>> 
>> I had a similar problem with my last boat. It would overheat and when I
>> would restart it would cool back down. It drove me nuts for 6 months. It
>> end up being the raw water impeller rubber delaminented from the brass
>> bushing.
>> 
>> Tim
>> 
>>> On Aug 26, 2017 12:54 AM, "Bev Wright" <bev.wright at verizon.net> wrote:
>>> 
>>> Mark,
>>> 
>>> Thanks for your post because, coincidentally, Whoosh #15 overheated on Wed
>>> night in Herring Bay/Chesapeake (opposite coast!) for the first time ever
>>> since I got her in 07/2014 and our boats are both 1993 vintage so I wonder
>>> if that's a sign of something?  I was motoring to the slip after engine had
>>> been running/idling for 90+ minutes (hanging out waiting for a race which
>>> didn't happen due to no wind) and noticed that temp was about 190° at 3000
>>> RPM. I throttled back to 2000 RPM and it cooled down immediately to normal
>>> 175°. I inched it back up to 2500 and it stayed at 175° for the remaining
>>> 20 min trip back to the slip. I had no smoke. Today I checked the strainer
>>> and it was clean. Oil, transmission fluid and coolant were OK and dry
>>> bilge. So, it's a mystery other than maybe she doesn't like to idle for
>>> that long. It was suggested that perhaps something was temporarily blocking
>>> the raw water intake. I will be cruising this weekend and will obviously
>>> keep an eye on it.
>>> 
>>> Bev Wright
>>> s/v Whoosh #15
>>> Deale, MD
>>> 
>>> -----Original Message-----
>>> From: C320-list [mailto:c320-list-bounces at lists.catalina320.com] On
>>> Behalf Of Mark Cole
>>> Sent: Friday, August 25, 2017 11:25 PM
>>> To: C320-List at Catalina320.com
>>> Subject: [C320-list] Perkins Perama M30 Overheating
>>> 
>>> My wife and I motored our boat over to a local boat yard for a haul-out
>>> yesterday.  About 20 minutes into the 1 hour trip, I noticed the water temp
>>> gauge was up to 220° and there was grey smoke (steam?) coming from the
>>> exhaust.  I shut the engine down and checked the raw water strainer.  There
>>> was a little gunk in the strainer, but not much.  Everything else looked
>>> OK, so I started the engine up again; there was cooling water coming out of
>>> the exhaust and water temp was back to normal.  We motored the rest of the
>>> way to the haul-out and the temp gauge stayed at 175° the whole way.  I
>>> went back to the boat this morning to start on the long list of stuff to
>>> do.  When I checked the bilge, there was maybe a gallon of water with
>>> antifreeze in the bilge.  I opened the heat exchanger on the engine,
>>> thinking it would be empty, but it was full.  When I dipped my finger in,
>>> it didn’t smell like antifreeze…  Is it possible that the heat exchanger
>>> burst when the water temperature went up?  Does that mean I could now have
>>> salt water in the engine block?  Anybody dealt with this before?
>>> 
>>> Mark
>>> Fiddler’s Green, #8
>>> Tacoma, Washington=
>>> 
>>> 
>