[C320-list] Overheating Perkins Perama M30

[amshd2 at aol.com]

I too have a 94 with a Perkins.

After I first purchased my 320 several years ago she started to run hot and I had a similar issue with old broken impeller debris trapped in the rubber cup connection on the front side of the heat exchanger.  I  also had a problem with the exhaust mixing elbow .  It had rusted up and the water was restricted from entering the elbow. I had to replace the elbow.   While I had things disassembled I pulled the brass core out of the heat exchange and checked  for clogs and cleaned it as well.

Put everything back together and it she again ran at a constant `180 degree F and still does.

I use a hand held laser temperature gauge and check it against the gauge on the boat from time to time.

Another thing you can check is the thermostat it may not be opening all the way. 


Tony  











-----Original Message-----
From: Glen <gmac570 at yahoo.com>
To: C320-List <C320-List at Catalina320.com>
Sent: Mon, Jul 9, 2012 10:18 pm
Subject: Re: [C320-list] Overheating Perkins Perama M30


On a similar year C320, we had overheat problems despite new impeller.  Found a 
uge amount of old impeller debris blocking the screen where the hose from the 
ater pump attaches to the heat exchanger, pulled the hose, cleaned all the 
ebris out of hose and screen, and overheat problem quit.  However if all your 
oses were replaced, I'd assume they would have found and removed any debris 
rom the heat exchanger screen.

ne other possibility is the heat exchanger itself being clogged by corrosion 
ver the years and not permitting adequate flow.

ope that helps.


From: Donald Poole <dpoole15 at gmail.com>
o: C320-list at catalina320.com 
ent: Monday, July 9, 2012 9:33 PM
ubject: [C320-list] Overheating Perkins Perama M30
First time out  in my recently purchased 1994 Catalina 320 (#0047). I had
hecked all fluids ( Oil, Transmission, Cooling water) before starting the
ngine. The coolant was low ( I had had most of  the engine hoses replaced
o I was not that surprised). After motoring about 10 minutes I noticed my
ngine heating up. Rose to ~220F.  I shut it down, let it cool, then
hecked the coolant level again. It was low. Started the engine and added
oolant with engine running assuming I had air in the system. Once full I
ecapped and continued to run. Engine crept up to 200F at a 1500-1800RPM
dle. Oh yes, I did check the raw water/exhaust discharge first and it
ppeared to be fine. A good bit of warm water exiting. I had also had the
aw water pump impeller replaced when they did the hoses. Looking for
uggestions as to what to check next.