[C320-list] White Smoke and Overheating Diagnosis (A Lesson)

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Christian

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Jun 1, 2021, 10:28:19 AMJun 1
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This list has taught me so much, other's stories have helped me, so I
thought I'd share an experience I had on Sunday, so others might learn.

I sail in Chicago, where we are on the hard for 7.5 months of the year.
Sunday, we launched, and launch day, though cathartic, is always a nerve
wracking shake down cruise for me of what's gonna go wrong now after being
on the hard. My yard is on a river, about mile-ish off Lake Michigan.

Before leaving the yard dock, was idling engine for about an hour, checking
engine temp (fine), exhaust flow (seemed a hair low, but wasn't terribly
concerned, just a mental note). After casting off, I had to wait for 2
bridges to be raised, requiring circling for about 45 mins with light load
on the engine. After we passed the second bridge, now revving to higher
RPM (about 25) I checked exhaust again, and noticed some light white smoke
from exhaust, steady stream. Started monitoring engine temp, and began
seeing the engine temp creep up slowly, going higher than normal (180), and
ticking up to about 190, still steady light white smoke. We went on to our
harbor, able to raise sails soon.

Got to mooring safely. Concerned I had coolant mixing with oil and was
burning coolant, once the engine cooled I checked oil color for milkiness.
Clean, and no oil burned. Checked coolant level, same level. Reading up
that night on white smoke, I read it's often steam or unburnt diesel.
Could be cooling problem, or could be a valve, timing, or injector pump
problem, crossed fingers it was cooling. Since I wasn't blowing white
smoke on cold engine start, only when engine got hot, this was likely
steam, and an overheating problem.

Monday, I went back to the boat to dive into problem. I'd replaced my
fresh water pump, thermostat, and mixing elbow 4 years ago, so eliminated
those as likely culprits. I'd just replaced impeller, so knew that wasn't
a likely culprit either. I took off the raw water strainer, clean. With
the bowl off, I opened raw water thru hull to inspect flow, just a
trickle. Interesting. So I took the hose off the sea cock, opened thru
hull again, barely a trickle. Felt into sea cock with pinky, felt squishy
stuff. Flash light showed white plastic shopping back pieces.

Luckily I keep a coat hanger on board for random needs like this. Bent an
end 90 degrees, went on a fishing expedition. Over the next 2 hours, I
worked out a complete plastic shopping bag that had been sucked into, and
deepy jammed, in the valve on my seacock. It was so jammed, at one point I
thought I would have to rebuild the seacock to free it, but eventually got
the entire bag out. Most of the time I had to rock the seacock lever back
and forth to inch the bag through the valve. Now seacock flowed perfect. I
think I picked up the plastic bag in the river, on our last Fall return to
yard, is my guess.

Hope this story helps others diagnose overheating problems, and the
importance of monitoring your exhaust, every sail. This random mishap
could have become a costly repair if I wasn't closely monitoring my exhaust
and engine temp. And happy 2021 sailing season for us Great Lake sailors!

-Christian Caperton
1994 C320 #138 "Canuck" Monroe Harbor, Chicago, IL

RONALD HODEL

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Jun 1, 2021, 10:59:50 AMJun 1
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Thanks for your story. It’s always good to have these stories lurking around in the back of the mind, hopefully able to be recalled at the proper time.

Ron Hodel
Lokomaikai #1070

Sent from my iPad

> On Jun 1, 2021, at 7:28 AM, Christian <cca...@gmail.com> wrote:
>
> This list has taught me so much, other's stories have helped me, so I

Chris White

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Jun 1, 2021, 11:04:12 AMJun 1
to c320...@catalina320.com, C320...@catalina320.com
Hi Christian
Thanks for the story.I had a similar experience some years ago and have since fitted a scoop inlet strainer.These are available in brass or composite.Once the boat is out of the water you can easily fit these over the existing water inlet.
Regards
Chris WhiteC320 #449 'Dandy'Hythe Marina VillageUK

Mike Mellon

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Jun 1, 2021, 11:12:20 AMJun 1
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We had an identical problem on LaVida with a plastic bag stuck in the
raw cooling water intake.  So apparently not unusual.  We overheated so
quickly we had to get a tow back to the berth, at night.  I'm going to
investigate the strainer idea.

Thanks.

Mike

LaVida 324
--
Michael Mellon
45 Ortalon Ave
Santa Cruz, CA 95060
mme...@cruzio.com
831-425-5583 Home

thruston18

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Jun 1, 2021, 11:13:23 AMJun 1
to C320...@catalina320.com
The previous owners of our last boat. Had installed a three way ball valve to the water intake for the engine. This could be hooked up the the galley sink or dock hose. To blow back things like this out.  We only ever used it once. But will be worth the trouble to install. We had to use it ourselves once when we sucked up weeds.  Just a thought. 

Sent from Yahoo Mail for iPhone

jackbrennan

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Jun 1, 2021, 12:15:09 PMJun 1
to C320...@catalina320.com
My story varies slightly. We were anchored in the Keys a couple of years ago when the diesel went hot on startup. Turns out some grass clogged the hose between the through hull and strainetr. Found it by accident when I noticed no water was coming into the strainer, even though the flow was fine from the through hull.Jack BrennanSonas, 1998 Catalina 320Tierra Verde, Fl.Sent from my Galaxy
-------- Original message --------From: Mike Mellon <mme...@cruzio.com> Date: 6/1/21 11:12 AM (GMT-05:00) To: c320...@lists.catalina320.com Subject: Re: [C320-list] White Smoke and Overheating Diagnosis (A Lesson) We had an identical problem on LaVida with a plastic bag stuck in the raw cooling water intake.  So apparently not unusual.  We overheated so quickly we had to get a tow back to the berth, at night.  I'm going to investigate the strainer idea.Thanks.MikeLaVida 324On 6/1/2021 8:03 AM, Chris White wrote:>   Hi Christian> Thanks for the story.I had a similar experience some years ago and have since fitted a scoop inlet strainer.These are available in brass or composite.Once the boat is out of the water you can easily fit these over the existing water inlet.> Regards> Chris WhiteC320 #449 'Dandy'Hythe Marina VillageUK>>      On Tuesday, 1 June 2021, 15:28:20 BST, Christian <cca...@gmail.com> wrote:>   >   This list has taught me so much, other's stories have helped me, so I> thought I'd share an experience I had on Sunday, so others might learn.>> I sail in Chicago, where we are on the hard for 7.5 months of the year.> Sunday, we launched, and launch day, though cathartic, is always a nerve> wracking shake down cruise for me of what's gonna go wrong now after being> on the hard.  My yard is on a river, about mile-ish off Lake Michigan.>> Before leaving the yard dock, was idling engine for about an hour, checking> engine temp (fine), exhaust flow (seemed a hair low, but wasn't terribly> concerned, just a mental note).  After casting off, I had to wait for 2> bridges to be raised, requiring circling for about 45 mins with light load> on the engine.  After we passed the second bridge, now revving to higher> RPM (about 25) I checked exhaust again, and noticed some light white smoke> from exhaust, steady stream.  Started monitoring engine temp, and began> seeing the engine temp creep up slowly, going higher than normal (180), and> ticking up to about 190, still steady light white smoke.  We went on to our> harbor, able to raise sails soon.>> Got to mooring safely.  Concerned I had coolant mixing with oil and was> burning coolant, once the engine cooled I checked oil color for milkiness.> Clean, and no oil burned.  Checked coolant level, same level.  Reading up> that night on white smoke, I read it's often steam or unburnt diesel.> Could be cooling problem, or could be a valve, timing, or injector pump> problem, crossed fingers it was cooling.  Since I wasn't blowing white> smoke on cold engine start, only when engine got hot, this was likely> steam, and an overheating problem.>> Monday, I went back to the boat to dive into problem.  I'd replaced my> fresh water pump, thermostat, and mixing elbow 4 years ago, so eliminated> those as likely culprits.  I'd just replaced impeller, so knew that wasn't> a likely culprit either.  I took off the raw water strainer, clean.  With> the bowl off, I opened raw water thru hull to inspect flow, just a> trickle.  Interesting.  So I took the hose off the sea cock, opened thru> hull again, barely a trickle.  Felt into sea cock with pinky, felt squishy> stuff.  Flash light showed white plastic shopping back pieces.>> Luckily I keep a coat hanger on board for random needs like this.  Bent an> end 90 degrees, went on a fishing expedition.  Over the next 2 hours, I> worked out a complete plastic shopping bag that had been sucked into, and> deepy jammed, in the valve on my seacock.  It was so jammed, at one point I> thought I would have to rebuild the seacock to free it, but eventually got> the entire bag out.  Most of the time I had to rock the seacock lever back> and forth to inch the bag through the valve. Now seacock flowed perfect.  I> think I picked up the plastic bag in the river, on our last Fall return to> yard, is my guess.>> Hope this story helps others diagnose overheating problems, and the> importance of monitoring your exhaust, every sail.  This random mishap> could have become a costly repair if I wasn't closely monitoring my exhaust> and engine temp. And happy 2021 sailing season for us Great Lake sailors!>> -Christian Caperton> 1994 C320 #138 "Canuck" Monroe Harbor, Chicago, IL>    -- Michael Mellon45 Ortalon AveSanta Cruz, CA 95060m...@cruzio.com831-425-5583 Home

Mark Cole

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Jun 1, 2021, 2:57:15 PMJun 1
to C320...@catalina320.com
I’ve had a similar issue (like lots of us have…). Started the boat in the slip and notices very little water in the exhaust so shut down to check. Turned out I had sucked a small fish into the raw water thru-hull! Poor little guy was stuffed in there so tight, I had to use a long drill bit through the seacock to clean him out. Ruined his day and my daysail.

Mark
Fiddler’s Green #8

P.F. Ross

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Jun 1, 2021, 3:05:53 PMJun 1
to C320...@catalina320.com
Christian,

Very similar thing here.

We were leaving on a multi-day cruise, boat was fully packed and we were
quite happy to finally be getting underway. I started the engine an hour
before we shoved off to get some heat on it and an instant after if fired
up I heard a light thump, not necessarily alarming but different. One
thing I have always done is to look at exhaust water (and listen to it as
well) after the engine has started. After 26 years of doing this, I knew
what it should look and sound like. The small stream coming out told me
something was wrong and I shut down the engine.

I went below to check the strainer and thru-hull. Strainer good, but when
I exercised the valve, I could not close it all the way so it was obvious I
had sucked up something. Since the thru hull is a 90 degree elbow
configuration, I figured It would not be easy to run a wire through so I
thought I might be able to flush it out with a water hose. I removed the
hose from the strainer end (and found very little flow) and was able to
make a good seal against the nozzle of my dock water hose and backflushed
it. I then found the thru hull valve would now move normally through its
full 90 degree travel so patted myself on the back.

We cast off but I was still cautious heading down our canal to the bay.
Good thing, too, since before we got to the end of our canal, water temp
was rapidly climbing. Fortunately, we were able to get turned around and
back to our dock without overheating although water temp was higher than I
had ever seen it (200 on my gauge).

At this point, it was about 2 o'clock on Fri afternoon and our trip was
about to be scuttled. Had we been in the Gulf, I would have gone in
myself, but the dark tannin waters of our canal are just a little too
creepy for me. Amazingly, I was able to get our diver out on very short
notice and he pulled most of (albeit somewhat shredded) a 13 gal white
trash bag out of the engine cooling water inlet. We were underway at 3pm
and barely made it to our first stop before dark.

So, all's well that ends well although next time our boat is on the hard I
will look into a scoop strainer.

Frank Ross
Beta Wave #206
Naples, FL



On Tue, Jun 1, 2021 at 11:15 AM jackbrennan <jackb...@bellsouth.net>
wrote:

> My story varies slightly. We were anchored in the Keys a couple of years
> ago when the diesel went hot on startup. Turns out some grass clogged the
> hose between the through hull and strainetr. Found it by accident when I
> noticed no water was coming into the strainer, even though the flow was
> fine from the through hull.Jack BrennanSonas, 1998 Catalina 320Tierra
> Verde, Fl.Sent from my Galaxy
> -------- Original message --------From: Mike Mellon <mme...@cruzio.com>
> Date: 6/1/21 11:12 AM (GMT-05:00) To: c320...@lists.catalina320.com
> Subject: Re: [C320-list] White Smoke and Overheating Diagnosis (A Lesson)
> We had an identical problem on LaVida with a plastic bag stuck in the raw
> cooling water intake. So apparently not unusual. We overheated so quickly
> we had to get a tow back to the berth, at night. I'm going to investigate
> the strainer idea.Thanks.MikeLaVida 324On 6/1/2021 8:03 AM, Chris White

Christian

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Jun 1, 2021, 3:09:14 PMJun 1
to C320...@catalina320.com
I too will be looking at a scoop after my next haul out.

Morale of the story is your exhaust, and color if present, is like tarot
cards for your engine, and problems, if you learn how to read them.

P.F. Ross

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Jun 1, 2021, 3:18:17 PMJun 1
to C320...@catalina320.com
After talking about strainers here, I recalled reading something about
them. It was Rod at marinehowto.com, who is not a fan. Food for thought.

https://marinehowto.com/external-strainers-omg/

Ken McCrimmon

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Jun 1, 2021, 3:28:24 PMJun 1
to C320...@catalina320.com
Novice C320 question, which is the raw water intake, so i know where to look on the outside if i have a problem
________________________________
From: C320-list <c320-lis...@lists.catalina320.com> on behalf of P.F. Ross <pfr...@gmail.com>
Sent: June 1, 2021 3:18 PM
To: C320...@catalina320.com <C320...@catalina320.com>

Christian

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Jun 1, 2021, 3:33:11 PMJun 1
to C320...@catalina320.com
Ken, on hull #138 (Perkins M30), mine is in the aft cabin, near the back,
under the cabin cushions, near center line of boat, behind the engine.
Externally, it sits almost above my prop. In my opinion, this is the most
important thru hull to be familiar with on your boat. You can sail with
the others closed, but not this one.

On Tue, Jun 1, 2021 at 2:28 PM Ken McCrimmon <kenmcc...@hotmail.com>
wrote:

Doug Treff

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Jun 1, 2021, 3:46:57 PMJun 1
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That three-way connection can also be used when winterizing to pull antifreeze through the system without having to disconnect hoses.

--
Doug Treff
do...@treff.us

Jon Vez

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Jun 1, 2021, 3:56:58 PMJun 1
to C320...@catalina320.com
One trick that works well to clear the hose and seacock is the air pump for your dinghy. The air pump hose conveniently fits just inside the hose end and usually takes just one pump at the low psi setting to blow everything out.
Just remove the hose from the strainer end and stick the pump hose in and you should clear everything out. This is one reason an external strainer may not be the best choice...

Sent from my iPad

Jack Brennan

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Jun 1, 2021, 4:17:45 PMJun 1
to C320...@catalina320.com
Just for the record, the absolute worst clog is the seacock for the holding tank.

Once you clear it, the sewage winds up in a hard-to-reach corner at the end of the holding tank. It does not seep directly into the bilge, so the cleanup is difficult and nasty.

Jack Brennan
Sonas, 1998 Catalina 320
Tierra Verde, Fl.



Sent from Mail for Windows 10

Mark Cole

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Jun 1, 2021, 4:26:52 PMJun 1
to C320...@catalina320.com
Ken;

As a little more background, our C320s use what is called a “raw water” cooling system to move combustion heat out of the engine, which is different from your car’s closed cooling system. A pump on your engine pulls water from the outside of the boat through a thru-hull, a closable seacock, a strainer and a heat exchanger before mixing that water with exhaust gasses in the mixing elbow and sending it out of the exhaust fitting in the stern of the boat. That is why you should always check your exhaust when you start your engine to make sure plenty of cooling water is coming out. Any of the parts in this system can, and often do, clog and cause the engine to overheat. The one part of the overheating puzzle that you have control over is opening the seacock in the raw water system before you start the engine.

To make matters worse, it is difficult to check this thru-hull from outside the boat unless you are hauled out since, like Christian mentioned, it is in the middle of the hull just behind the engine. This means that most often, you are trouble shooting overheating issues from inside the boat, in the water.

Mark
Sent from my iPad

> On Jun 1, 2021, at 12:33 PM, Christian <cca...@gmail.com> wrote:
>
> Ken, on hull #138 (Perkins M30), mine is in the aft cabin, near the back,

Joe Jablonowski

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Jun 1, 2021, 4:45:26 PMJun 1
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My 1994 C320 w/Perkins 30 engine is fitted with a T fitting between the raw-water seacock and the water strainer. The T accepts a short garden hose but is normally capped.
If I suspect a clog in the seacock, I'll temporarily close that valve, twist on a short garden hose (beats tearing off a rubber hose from the Marelon fitting). Then, with the open end of the garden hose held above the waterline, I'll open the seacock and use an air horn to blast out the debris.
BTW, the garden hose helps in sucking in pink antifreeze when it comes time to winterize.
- Joe Jablonowski  s/v Assignment #103

=================================================================
On Tuesday, June 1, 2021, 04:17:45 PM EDT, Jack Brennan <jackb...@bellsouth.net> wrote:

Just for the record, the absolute worst clog is the seacock for the holding tank.

Once you clear it, the sewage winds up in a hard-to-reach corner at the end of the holding tank. It does not seep directly into the bilge, so the cleanup is difficult and nasty.

Jack Brennan
Sonas, 1998 Catalina 320
Tierra Verde, Fl.



Sent from Mail for Windows 10

From: Jon Vez
Sent: Tuesday, June 1, 2021 3:56 PM
To: C320...@catalina320.com

Christian

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Jun 1, 2021, 5:23:21 PMJun 1
to C320...@catalina320.com
Great explanation Mark!

One more thing I'll add. It was both terrifying (to me) and exhilarating,
opening the raw water seacock with the hose off. And it was a nice
learning experience watching the flow rate once I cleared the logging jam.
Even though I had control of the lever, I kept on thinking here I am,
opening a hole in my hull, imma gonna sink my boat, as that water rushes at
a good rate.

Mark Cole

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Jun 1, 2021, 5:29:24 PMJun 1
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No kidding! I’m about to swap out depth transducers with the boat in the water, so I’m trying to prepare myself for that gusher.

Sent from Mark's iPhone
Smooth seas never made a good sailor.

> On Jun 1, 2021, at 2:23 PM, Christian <cca...@gmail.com> wrote:
>
> Great explanation Mark!

P.F. Ross

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Jun 2, 2021, 1:06:18 AMJun 2
to C320...@catalina320.com
Terrific ideas from Jon and Joe about using a blast of air or gas to blow
out the raw water intake!

Is this list great or what?

Frank Ross
Beta Wave #206

Chris Nichols

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Jun 2, 2021, 4:39:28 AMJun 2
to C320...@catalina320.com
In using a blast of air approach it may be a good idea to ensure the pressure is only directed towards the thru- hull. If you are using a tee-connector then the pressure will also blow water towards the engine. I’m not sure how likely it would be to get past the pump impeller but if it did so then there might be a small risk of water entering a cylinder via an open exhaust valve. Particularly if you have an old exhaust elbow that is partially clogged. Given back-pressure etc I guess the risk is low but it could turn an overheating glitch into an engine rebuild.

Chris

> On 2 Jun 2021, at 06:06, P.F. Ross <pfr...@gmail.com> wrote:
>
> Terrific ideas from Jon and Joe about using a blast of air or gas to blow
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