[C320-list] Overheating Engine

[Jeff Hare]

Not to drag this out, but we had this issue a couple years ago and was getting progressively worse. It was especially hard to get a prime after cleaning the strainer. 

Replaced the raw water pump assembly for about $160 and the exhaust was like a firehose by comparison. No priming issues since. It was worth the cash, and we doused the old one and a rag with WD40 and keep it in a ziplock bag as a spare as the yanmar guy suggested. 

-Jeff

Joseph Aberdale <summerwind3 at comcast.net> wrote:

Hi To All,

Thanks very much for your responses which were of great help.

The raw water intake and filter were clean. I removed the water pump 
output hose and started the engine. The pump put out plenty of water 
and the belts are not slipping. After several starts, I learned that 
if I start the engine at mid to 3/4 throttle and let it run at that 
rpm for a minute, water is expelled out of the discharge hull 
fitting. I can then lower the throttle and it will continue to 
discharge. However, if I start the engine at a low throttle setting, 
water will not discharge from the hull without revving up the engine 
to at least 1/2 throttle. Is this normal?

Also, regardless of the throttle setting, water discharges from the 
hull fitting in spurts EVERY OTHER SECOND - NEVER A CONTINUOUS FLOW. 
Is this normal?

Regarding the fresh water failing to flow through the faucets. I 
disassembled the filter by the pump and found it all clogged up with 
gunk. After cleaning it and reassembling the filter, water again 
refused to come through the faucet. I disassembled the filter again 
and found it to be completely blocked again. I obviously have to 
drain the water tanks to remove the gunk. Is using a small pump 
attached to an electric drill the easiest way to do that?

Thanks again for your responses.

Bob - I sail out of Wellfleet. Cape Cod.

Joe
#908

On Jul 6, 2011, at 9:28 PM, Robert Seastream wrote:

> Joe, we're near brothers as I own hull 906. We likely have the 
> same (3GM30F) Yanmar engine. It circulates raw seawater over a 
> 'heat exchanger'. That exchanger has the coolant/antifreeze in 
> it. If you're not seeing raw water expelled out of the discharge 
> hull fitting I'd suspect the following in order: The belt (is it 
> slipping?), the impeller, or impeller housing (are they drawing 
> water?).
>
> As to your freshwater pump problems, I'd look at the pump input 
> filter to see if it's clogged. Sux to do, as Catalina placed the 
> freshwater pump under the aft bunk. If it's clear, then I'd 
> suspect the pump itself. I replaced mine because I wanted a pump 
> with a higher GPM output...5.0 vs the 2.? of the original.
>
> We're cruising Casco Bay for the next two weeks, but I can be 
> reached (when in range) via my cell at 603-475-4410. Where do you 
> hail/sail from?
>
> Bob Seastream WB2DWD
> Intuition # 906
>
>
> On Jul 6, 2011, at 5:27 PM, Pat Ireland wrote:
>
>> Joe - What I know, I learned from this site. Don't be 
>> discouraged. It's
>> been a busy weekend.
>>
>> Suggestion for what to do when no one answers immediately. Go to the
>> Catalina 320 International site and click on discussion. There is 
>> a link
>> there to the forum posts. On the upper right of that page is a 
>> field to
>> input your search criteria. "engine cooling water" or "no 
>> water" or
>> "pressure water" are examples that might work.
>>
>> On the engine water problem - Was the water coming out of the 
>> exhaust after
>> you changed the impeller a strong or weak flow? If it was weak, you
>> may have a worn pump. If it was strong, then something else like 
>> a new clog
>> may be the problem.
>>
>> Several owners have found that sand pulled into the pump has 
>> damaged the
>> impeller cover plate enough that replacement is required. It may be
>> possible to polish out scratches and grooves to get a bit of extra 
>> life out
>> of the cover.
>>
>> On the pressure water problem - if you are not seeing fresh water 
>> in the
>> bilge, you may have the water line valves turned off or the pump 
>> may be
>> plugged. There is a screen in the pump intake that may have 
>> collected
>> debris and need a cleaning.
>>
>> Good Luck
>>
>> Pat, 801
>>
>> On Wed, Jul 6, 2011 at 12:58 PM, Donald Lawson <dnclaws at aol.com> 
>> wrote:
>>
>>> Joe
>>> I sail/motor in heavy kelp and eel grass infested areas. Clogs 
>>> my intake
>>> thruhull and filter and destroys my impellers. I start at the 
>>> thru hull,
>>> intake filter and lines to the pump. If all clear pull the output 
>>> line off
>>> the pump, turn engine over and check pump output. If good then go 
>>> to the
>>> elbow in the exhaust riser, it might be plugged. If all of that 
>>> is good
>>> then???
>>> Don #1005
>>> On Jul 5, 2011, at 7:01 PM, Joseph Aberdale wrote:
>>>
>>>> Today I started the Yanmar engine in my 2002 C320 and the 
>>>> overheating
>>> light and alarm went on. I discovered that engine cooling water 
>>> was not
>>> being discharged from the hull but you could see the discharge of 
>>> air.
>>> Further investigation revealed that water was being drawn in 
>>> through the
>>> intake and getting to the engine. Is the likely problem the water 
>>> pump? I
>>> recently installed a new impeller and the engine ran well after 
>>> that. How do
>>> I determine if the water pump is bad?
>>>>
>>>> Also, I cannot get water to run out of the galley and bathroom 
>>>> faucets.
>>> The tanks are filled and I can hear the water pump operating but 
>>> do not get
>>> any running water. Any thoughts on how I should proceed from here?
>>>>
>>>> Thank you very much.
>>>>
>>>> Joe
>>>> #908
>>>>
>>>
>>>
>