[C320-list] White Smoke from Diesel Exhaust

[Bob Borelli]

Thank you Albert, I will pull the exhaust elbow & check for carbon build up.  I have thinking about replacing the elbow with new plus exhaust hose.
I have followed the posts for adding hump hose, purchase one, measured onboard, not enough room to fit in 12" lenght of hose tween elbow & muffler nipple.

Thank you Elliot, I will start the diesel, warm it up to idle 1000 rpms, remove the oil cap & find out if air blowing out to check for blow by.  I will also test at 2800 rpms.

Thank you Rich,  for the last 3 seasons I have been taking & logging temperature measurements at various locations on the M30 using a 'Laser Infrared Thermometer Temp Gun'.
I take temp readings at the same locations after M30 has been operating at 2800 rpms & the Control Panel temp gauge reads 190F.
Always 190F unless overheat, I know this gauge works.

I measure at the:

  1.  Hull bottom for water temperature
  2.  Stuffing tube
  3.  Raw water & exhaust hose between elbow & aqua muffler
  4.  Raw water & exhaust discharge elbow
  5.  Rubber cap from manifold to elbow
  6.  Top of exhaust manifold
  7.  Side of exhaust manifold
  8.  Engine block beside oil filter
  9.  Cylinder head
  10. All 3 fuel injectors at their base at cylinder head
  11. Water pump
  12. Raw water pump.

Over the past 200 engine hours these temps have been similar, so no indications from them.  Worth doing this?
Open the radiator cap, the anti-freeze is circulating & no bubbles appear that might indicate blown head gasket.
Never need to add anti-freeze or oil during the season.
Raw water impeller ok, good flow from overboard exhaust.  No smoke on start up.  M30 starts quickly even with low battery volts.
I plan to have the marina pull the injectors & send their shop, start here.
And Compression Test!
Any additional thoughts, comments are most appreciated.

Bob Borelli 1995 Catalina 320 no. 209 at Sailing Associates Inc, Georgetown MD.



________________________________
From: C320-list <c320-list-bounces at lists.catalina320.com> on behalf of Rich Allen via C320-list <c320-list at lists.catalina320.com>
Sent: Wednesday, November 8, 2023 7:13 PM
To: C320-List at catalina320.com <C320-List at catalina320.com>
Cc: Rich Allen <randnallen at gmail.com>
Subject: Re: [C320-list] White Smoke from Diesel Exhaust

Hi Bob,
I am hoping that your issue is due to one of the less invasive causes.  I
received a big dose of education stemming from a problem caused by rings
stuck in the piston grooves (1995 Westerbeke 30B, 1170 hours).  In my case,
the engine started and ran fine, until one time it did not start after
repeated attempts to start.  There was low compression in cylinders 1 and
2.  The stuck rings cause blowby observed by smoke coming from the
crankcase from the dipstick hole with the dipstick removed.  A compression
test is pretty quick and easy to do if you have the equipment, and that
would narrow your search.  A good diesel mechanic would have the tools
available, though these mechanics seem to be difficult to find.  If you
want to do the compression test yourself, a test kit is available from
Harbor Freight for not too much, but be aware that diesel engines are
higher compression than gas so a higher pressure gauge is needed.  The
compression can be tested through the glow-plug holes.  How are you
determining the temperature at the various injectors?  A stuck-open
thermostat could  interfere with the engine operating temperature which
you should see on the control panel.  You can test the thermostat in a pot
of water to see that it opens at the proper temperature, or a replacement
is not too expensive to rule it out.

I hope you get resolution without needing a rebuild. Keep us all informed
with what you find.

Best regards,
Rich Allen, Destiny 1995 #265

On Wed, Nov 8, 2023 at 2:37 PM Elliott Womack via C320-list <
c320-list at lists.catalina320.com> wrote:

> Check for blow by. With the engine running bring the rpm up a bit, and go
> remove the oil fill cap. Place your hand over the fill and see how much air
> you feel blowing. It should NOT feel like a small shop vac blowing.
>
> On Wed, Nov 8, 2023, 1:17 PM Albert Kitten via C320-list <
> c320-list at lists.catalina320.com> wrote:
>
> > Is the mixing elbow blocked with carbon deposits?
> >
> > On Thu, 9 Nov 2023, 4:55 am Bob Borelli via C320-list, <
> > c320-list at lists.catalina320.com> wrote:
> >
> > > My diesel exhaust is emitting white smoke, possibly blue white, about 3
> > to
> > > 4 feet long at operating speed of 2800 rpms.  The smoke remains at the
> > > water surface until dissipating.   No smoke at start up or idle at 1000
> > > rpms.  This 1995 Perkins M30 diesel has 1560 hours.
> > >
> > > The diesel is not overheating.  I have had the underwater hull cleaned.
> > > Appears to be good raw water overflow from the exhaust.  Various
> > > temperature readings around the diesel & exhaust at operating speed of
> > 2800
> > > rpms have remained the same.  No loss of coolant.  Raw water impeller
> > > good.  No water in the Racor bowl.  Fuel filters new.   Additives used
> > are
> > > Biobor MD & JF.  Fuel  purchased fuel from truck stop.
> > >
> > > The no. 1 injector temp (197F) is less then no. 2 & no. 3 (220F).     I
> > > don’t know if injectors have been serviced in the 1560 hours.  The tech
> > > manual states service after 900 hours.  My plan is to have the
> injectors
> > > removed for testing.
> > >
> > > Has anyone had similar white smoke issues from their diesel?  And how
> > > resolved?
> > >
> > >
> > >
> > >
> > >
> > > What creates White Smoke from diesel exhaust?
> > >
> > > White Smoke is nearly always water vapor & is quite normal when engine
> is
> > > first started.
> > >
> > > However if it persist for more then a few seconds, engine could have
> > > problems:
> > >
> > >
> > >
> > > White Smoke indicates Overheating!  Steam! Due to restricted Injection
> > > Elbow!  Test by measure the temperature in the ‘Wet’ portion of Exhaust
> > > Hose, should be below 200F. insufficient raw water flow.
> > >
> > >
> > >
> > > Overcooling - cylinder head & combustion chamber operate at
> temperatures
> > > too low for proper combustion (my cylinder no.1 lower temp?)
> > >
> > >
> > >
> > > White Smoke represents atomized fuel, very small droplets of fuel that
> > > cause a fog.
> > >
> > > White Smoke from exhaust indicates diesel fuel not burning correctly -
> > the
> > > Injectors.
> > >
> > > Fuel is not burning completely.   Replace fuel Injector.
> > >
> > > Raw diesel fuel is passing thru combustion chamber into the exhaust
> > stream.
> > >
> > > White smoke unburned fuel indicates damaged injectors.
> > >
> > >
> > >
> > > Preheat device - Glow Plugs malfunctioning?
> > >
> > >
> > >
> > > Poor fuel quality (not formulated as no. 2 diesel), add fuel Cetane
> > > Booster may temporarily alleviated & identify poor quality fuel as
> > > problem.  Contaminated Fuel.  Water in the fuel.
> > >
> > >
> > >
> > > Low pressure to the fuel pump.  Damaged or incorrect fuel pump timing.
> > > Dirty fuel filter.
> > >
> > >
> > >
> > > Poor Atomization of Fuel - Injectors
> > >
> > > Injector nozzle stuck open [1].    Injector nozzle seat worn [1].
> > >  Injector pressure low [1].
> > >
> > > Low fuel grade [4].   Injection timing retarded [4].
> > >
> > >
> > >
> > > Poor Compression:
> > >
> > > Low cylinder compression.   Leaking inlet or exhaust valve [3].
>  Piston
> > > rings stuck in grooves [3]
> > >
> > > Worn piston rings and cylinders [3].  Piston ring blow by.    Damages
> > > rings.
> > >
> > >
> > >
> > > Water in the fuel:
> > >
> > > Check Coolant Level
> > >
> > > Coolant working its way into cylinders & burning along with the fuel.
> > >
> > > Blown Head gasket - cooling water escaping from galleries & entering a
> > > combustion chamber.
> > >
> > > Water mixed in fuel from cracked head gasket, cylinder head or block.
> > >
> > >
> > >
> > > ·          Inspect Valve Seals for signs of leakage.   Poorly adjusted
> > > valves or worn valve seats.
> > >
> > >
> > >
> > > ·          Cracks in Intake Manifold Gasket
> > >
> > > ·          Cracks in Head Gasket or Head gasket blown.
> > >
> > >
> > >
> > > ·          Cracks in cylinder head
> > >
> > > ·          Cracks in exhaust manifold.
> > >
> > > ·          Cracks in engine block.
> > >
> > > ·          Inspect Piston Rings for signs of leakage.
> > >
> > >
> > >
> > > ·          Damaged timing gear
> > >
> >
>