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

[Mark Cole]

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

> On Jun 1, 2021, at 9:14 AM, jackbrennan <jackbrennan at 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 <mmellon at cruzio.com> Date: 6/1/21  11:12 AM  (GMT-05:00) To: c320-list at 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 <ccaper at 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 95060mmellon at cruzio.com831-425-5583 Home