Reply
 
Thread Tools Display Modes
 
Old 01-10-2016, 10:22 AM   #21
Senior Member
 
oscar's Avatar
 
City: Bethlehem, PA
Country: United States
Vessel Name: Lady Kay V
Vessel Model: Don't know yet.....
Join Date: Oct 2015
Posts: 420
Quote:
Originally Posted by Hawgwash View Post
And the survey sez...what temp would that be Bucky?
Most of the old Detroit afficionados say 30 seconds.......
__________________
Advertisement

__________________
Currently boatless but looking. Avatar is my first boat....Holland, 1965 ish.....
oscar is offline   Reply With Quote
Old 01-10-2016, 10:40 AM   #22
TF Site Team
 
Baker's Avatar
 
City: League City, Tx
Country: Texas
Vessel Model: Carver 356
Join Date: Oct 2007
Posts: 5,633
Quote:
Originally Posted by oscar View Post
As said above glow plugs are for starting only, and some engines don't have them. My old Yanmar and the 2-stroke Detroits come to mind. There are others.
I would say MOST marine engines don't have them. I have owned 5 marine diesels(Volvo, 2 types of Perkins, Yanmar, Cummins) and none had glow plugs. I was told the higher compression engines(>18:1) do not have them installed.

My Cummins smoke like crazy when they are started in cold weather. But they clear up quickly.
__________________

__________________
Prairie 29...Perkins 4236...Sold
Mainship Pilot 30...Yanmar 4LHA-STP...Sold
Carver 356...T-Cummins 330B
Baker is offline   Reply With Quote
Old 01-10-2016, 10:50 AM   #23
Guru
 
City: gulf coast
Country: pinellas
Join Date: Jun 2014
Posts: 2,199
folks might want to reread the OP
Quote:
we have had black smoke come out of our exhausts when under full load.
Engines under full load are warmed up or will be very shortly.
bayview is offline   Reply With Quote
Old 01-10-2016, 10:54 AM   #24
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 3,889
Glow plugs mostly only in small diesels with combustion chamber offset from cylinder. Kubotas, smallish genset engines, small sailboat engines, old Volvo tamd40, gm 6.2/6.5 v8, etc. Called precombustion chamber, prechamber, indirect injection, etc. Usually compression ratio is even higher, like 20-24:1. Most of these will NOT start unless preheated. Quieter under load, but lower efficiency.

Larger engines are direct injected, with nozzle spraying right into cylinder. Comp ratio 14-17:1 typical. No glow plugs needed to start, but some have air heaters to help when cold. Noisier combustion but much better thermal efficiency.

The trend is going away from prechambers, mostly due to poor efficiency. Not an issue with the really little engines, the efficiency penalty is not really a factor there. So little prechamber engines are still in production.
Ski in NC is offline   Reply With Quote
Old 01-10-2016, 11:00 AM   #25
Guru
 
City: Melbourne, FL
Country: USA
Join Date: Dec 2014
Posts: 918
Quote:
Originally Posted by FF View Post
"Cold diesel engines smoke very black smoke due to incomplete combustion. It can't combust well due the glow plugs not getting hot enough to ignite the fuel cleanly"

Sorry,

Cold diesels that are just started or are not up to temp will exhaust WHITE smoke , which is unburned fuel.

Engines with pre-combustion chambers usually need glow plugs to START ,
but they do not usually operate while the engine is operating .
I guess it depends on the engine...

Glow plugs are powered on cold days to preheat them to ignite the fuel. Once the engine is running, the glow plug tips stay red hot from the ignition of the previous cycle. you're sort of correct, in that they are not powered during operation of the engine, but that does not mean they are 'working'.
stubones99 is offline   Reply With Quote
Old 01-10-2016, 11:13 AM   #26
Wannabe
 
Britannia's Avatar
 
City: SF Bay Area
Country: USA
Vessel Name: Stillwater
Vessel Model: Kadey-Krogen 54
Join Date: Dec 2014
Posts: 766
Quote:
Originally Posted by oscar View Post
As said above glow plugs are for starting only, and some engines don't have them. My old Yanmar and the 2-stroke Detroits come to mind. There are others.
My 1996 John Deere 6068T does not have glow plugs.

Richard
Stillwater KK54 #5
Britannia is offline   Reply With Quote
Old 01-10-2016, 11:22 AM   #27
Guru
 
koliver's Avatar
 
City: Saltspring Island
Country: BC, canada
Vessel Name: Retreat
Vessel Model: C&L 44
Join Date: Nov 2007
Posts: 2,174
Your bottom and/or props may now be fouled to the point that you can n longer get to your normal full speed without overloading the engines.
EG: when I moved my boat from a shelter to open moorage for the summer months, the increased growth in two months covered my props (all running gear too) with 1/2" to 3/4" barnacles. I couldn't get above 5 knots without black smoke from both engines. Once the barnacles were removed, the smoke went away, even at over 8.5 knots (above normal cruise).
koliver is offline   Reply With Quote
Old 01-10-2016, 05:30 PM   #28
Guru
 
River Cruiser's Avatar
 
City: UMR MM283
Country: US
Vessel Name: Northern Lights II
Vessel Model: Bayliner 3870
Join Date: Jan 2013
Posts: 1,228
Quote:
Originally Posted by Capt.Bill11 View Post
Are you sure your bottom and props are clean?

I had the same problem a few years ago and it was a dirty bottom, no problems with the props in freshwater.


Sent from my iPad using Trawler Forum
__________________
Ron on Northern Lights II
I don't like making plans for the day because the word "premeditated" gets thrown around in the courtroom.
River Cruiser is offline   Reply With Quote
Old 01-12-2016, 12:11 PM   #29
Member
 
City: San Diego, CA
Country: USA
Vessel Name: Gloria Arlene
Vessel Model: Californian LRC 34
Join Date: Nov 2014
Posts: 8
Reply to Thread re Black Smoke

Quote:
Originally Posted by C lectric View Post
Full load, what specifically do you mean? Normal cruise rpm OR did you push the throttle all the way for max. rpm [WOT]? If full rpm , WOT, then have you done that before? What were the results before? What rpm was reached.?

By suddenly do you mean BETWEEN this run and the last run OR do you mean while you were out on this run and all of a sudden they started black smoking?

Cold weather should have no effect except to increase air from cooler, denser air, which the engine should like. Diesels like all the air they can get unlike gas engines.
.
Black smoke can be caused by several problems. It is almost always either overload or lack of air.
OVERLOAD
-props incorrect
-props fouled or damaged
-fouled bottom
-too much added weight which sneaks up compared to the way the boat was when new[er].

Since this happened suddenly and to both engines [ is that correct???] then I doubt the props are wrong but they could have been fouled by a line or seaweed. Not big enough to stall the engines but it would goof up the normal water flow and add a lot of load. Try a diver and get the props checked for fouling.

LACK OF AIR
-air filters, turbo, aftercooler, exhaust system,

Have you looked in the engine compartment.? At the air filters? If they are dirty that will cause insufficient air for the engines and black smoke. If you have an exhaust leak that will allow soot to plug the filters and that plugging can be quite quick. Soot should be quite noticeable. Regardless, Try changing the filters. It may be that plugging , if that is the case, reached a point where you noticed especially if you ran the engine a bit harder than normal. If this is the case then eventually it would have made itself known even at lower rpm.

I suggest checking/cahnging the air filter first since they are relatively cheap to replace and should be little effort. Also the diver as he/she too will be relatively cheap.
Some of the other things are going to take some work to do and some, possibly serious, expense to find and sort out.


Report back what you check and do.
Thanks for your reply. By all of a sudden, I meant to imply that we have been on cruises both somewhat local and intermediate (San Diego to/from Catlalina) and we have not had a black smoke problem. The marine repair company that I am dealing with has indicated that they think that this is a prop setting problem; however, with no change in the props, I wonder how this could happen "suddenly."

This all started after, when my boat was taken out to get the bottom cleaned, the inspection indicated a problem with my struts and drive shaft. I got those issued fixed. Could the prop settings (I apologize if I have that wrong) have been disturbed during this repair process?

I appreciate your input and that of all of the forum members.

JE

I have checked the Air Filters and they are clean and in good order.
jenglishsr is offline   Reply With Quote
Old 01-12-2016, 12:36 PM   #30
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 16,531
"This all started after, when my boat was taken out to get the bottom cleaned, the inspection indicated a problem with my struts and drive shaft. I got those issued fixed. Could the prop settings (I apologize if I have that wrong) have been disturbed during this repair process? "

The "prop setting" the pitch, is only changed with great effort by hammering it in shape on pitch blocks

AHHHA!

If the shaft and struts are not properly aligned there could be enough extra load to overload at full throttle.

With the engine off , just how hard is it to turn the prop shaft in neutral?

The stuffing box will give some resistance , but with a screwdriver between the coupling bolts movement should be 10-30 lbs , not 100 + to move the shaft a full 360 deg.
FF is offline   Reply With Quote
Old 01-12-2016, 03:20 PM   #31
TF Site Team
 
Baker's Avatar
 
City: League City, Tx
Country: Texas
Vessel Model: Carver 356
Join Date: Oct 2007
Posts: 5,633
Quote:
Originally Posted by jenglishsr View Post
Thanks for your reply. By all of a sudden, I meant to imply that we have been on cruises both somewhat local and intermediate (San Diego to/from Catlalina) and we have not had a black smoke problem. The marine repair company that I am dealing with has indicated that they think that this is a prop setting problem; however, with no change in the props, I wonder how this could happen "suddenly."

This all started after, when my boat was taken out to get the bottom cleaned, the inspection indicated a problem with my struts and drive shaft. I got those issued fixed. Could the prop settings (I apologize if I have that wrong) have been disturbed during this repair process?

I appreciate your input and that of all of the forum members.

JE

I have checked the Air Filters and they are clean and in good order.
I am thinking they screwed something up with your alignment. What exactly did they do????
__________________
Prairie 29...Perkins 4236...Sold
Mainship Pilot 30...Yanmar 4LHA-STP...Sold
Carver 356...T-Cummins 330B
Baker is offline   Reply With Quote
Old 01-12-2016, 04:21 PM   #32
Guru
 
Join Date: Apr 2014
Posts: 1,291
What ever the cause of your smoke the issue brings up why a boat owner should understand the sea Trial procedure and regularly check the performance of the engine or engines. By doing so problems will be noticed early. If your hull is dirty or your air filters clogged or bad fuel etc. etc.
eyschulman is offline   Reply With Quote
Old 01-12-2016, 05:13 PM   #33
Guru
 
City: Sydney
Country: Australia
Join Date: Jul 2015
Posts: 1,354
1 engine is understandable but 2 ??? I say there's a lot more to the story for anyone to even guess
gaston is online now   Reply With Quote
Old 01-12-2016, 05:17 PM   #34
Guru
 
Northern Spy's Avatar
 
City: Powell River, BC
Country: Canada
Vessel Name: Northern Spy
Vessel Model: Nordic Tug 26
Join Date: Feb 2012
Posts: 2,671
Excessive idling causing coked up turbos?

Yes, this is "Easter egg" troubleshooting, but I haven't seen it mentioned yet. Just another possible cause.
Northern Spy is online now   Reply With Quote
Old 01-12-2016, 06:56 PM   #35
Guru
 
Xsbank's Avatar
 
City: Pender Harbour, BC
Country: Canada
Vessel Name: Gwaii Haanas
Vessel Model: Vancouver Shipyards Custom Aluminum 52
Join Date: Sep 2013
Posts: 2,447
Unless the engines were realigned IN THE WATER after the shaft issues in the yard, my guess is they are far enough out to add too much drag, hence the sudden smoke.

Did they align in the water?
__________________
Don't believe everything that you think.
Xsbank is offline   Reply With Quote
Old 01-12-2016, 10:14 PM   #36
Senior Member
 
oscar's Avatar
 
City: Bethlehem, PA
Country: United States
Vessel Name: Lady Kay V
Vessel Model: Don't know yet.....
Join Date: Oct 2015
Posts: 420
Quote:
Originally Posted by Baker View Post
I am thinking they screwed something up with your alignment. What exactly did they do????
Yeah.... all arrows point here.
__________________
Currently boatless but looking. Avatar is my first boat....Holland, 1965 ish.....
oscar is offline   Reply With Quote
Old 01-12-2016, 10:36 PM   #37
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 3,889
Alignment would have to be horribly off to overload engines. And if that bad, it would wreck things.

How hard is it to hand rotate shafts?

And is it absolutely KNOWN that the bottom and wheels are clean? How long has boat been in the water since last haul or last cleaning?
Ski in NC is offline   Reply With Quote
Old 01-12-2016, 10:36 PM   #38
Scraping Paint
 
City: -
Country: -
Join Date: Oct 2007
Posts: 13,748
Quote:
Originally Posted by jenglishsr View Post
This all started after, when my boat was taken out to get the bottom cleaned, the inspection indicated a problem with my struts and drive shaft. I got those issued fixed. Could the prop settings (I apologize if I have that wrong) have been disturbed during this repair process?
Having just been through a four month issue with running gear ourselves it is easy to envision the possibility that the additional load your engines are seeing was caused by actions the yard took to correct whatever your initial problems were. This could have resulted in increased friction due to misaligned engines, misaligned struts, incorrectly sized cutless bearings, bent shafts, shaft couplers not properly aligned with the shafts or mated to the transmission output flange, improper clearance between the shafts and the insides of the packing glands, bent shaft log hoses, or something else putting enough pressure on the components to increase the drag and thus the load on the engines causing them to work too hard, hence your black smoke.

Our situation had nothing to do with alignment or engine load but I know how easy it can be for several things to change when one thing in the system is changed or worked on.

You mention the yard found problems with your "struts and driveline." Does this mean both sides or just one?

Do you know if your shafts were easy or relatively easy to turn by hand from inside the engine room before, and if they were, are they still that way? If there is no change in the effort needed to turn them, that does not mean that misalignment of some sort is not the culprit. But if there is a difference in the effort to turn them that can be a clue that misalignment of something could be the problem.

Unless you had the props worked on they should be the same as they were before your haulout. And if they were clean when the boat went back into the water it would be surprising if both of them got fouled enough (depending on how long it's been since your haulout) to have such a severe effect, although with boats one soon learns to never say never.

Black smoke notwithstanding, does the boat feel like it's doing the same speed and going through the water in the same way at the same power settings now as it has in the past? Don't know about your boat but when ours is nearing the need for a haulout with significant bottom, prop and rudder growth we can feel the difference in the hull's movement through the water, to say nothing of seeing it on the knotmeter.
Marin is offline   Reply With Quote
Old 01-12-2016, 11:10 PM   #39
Senior Member
 
Steve DAntonio's Avatar
 
City: Deltaville
Country: United States
Join Date: Dec 2015
Posts: 108
If both engines are doing it, all of a sudden, and they never smoked before, it couldn't be a prop pitch issue. It's more likely growth on the props, it doesn't take much to create excess drag, which mimics an over-pitched prop, which will cause over-fueling and smoke. Also, have you ever done a wide open throttle run, prior to this problem, and if so did the engiens achieve the rated rpm? If so, it would be worth briefly doing that again, if they don't achieve the WOT rating, then a problem exists, again likely fouled props, as it's unlikely that both engines are experiencing a valve or turbo problem. Contaminated fuel can cause smoke, but that's less common.

Propellers that are properly matched to engines allow the engine to run up to the WOT rating established by the engine manufacturer, and ideally just a little bit more, 20-50 rpm, which ensures the engine can never be overloaded, even if the boat gains weight over its lifetime. Even if you never run at this rpm, it's important that this match be achieved.

Before a prop is ever re-pitched, the exhaust system back pressure should be checked (excess back pressure robs an engine of horse power, as well as violating engine manufacturer's application guidelines), turbo turbine inspected, and valves adjusted. Far too many props are re-pitched to adjust rpm, only masking other problems in the process.
__________________
Steve D'Antonio
Steve DAntonio is offline   Reply With Quote
Old 01-14-2016, 09:11 AM   #40
Member
 
City: San Diego, CA
Country: USA
Vessel Name: Gloria Arlene
Vessel Model: Californian LRC 34
Join Date: Nov 2014
Posts: 8
Quote:
Originally Posted by FF View Post
"This all started after, when my boat was taken out to get the bottom cleaned, the inspection indicated a problem with my struts and drive shaft. I got those issued fixed. Could the prop settings (I apologize if I have that wrong) have been disturbed during this repair process? "

The "prop setting" the pitch, is only changed with great effort by hammering it in shape on pitch blocks

AHHHA!

If the shaft and struts are not properly aligned there could be enough extra load to overload at full throttle.

With the engine off , just how hard is it to turn the prop shaft in neutral?

The stuffing box will give some resistance , but with a screwdriver between the coupling bolts movement should be 10-30 lbs , not 100 + to move the shaft a full 360 deg.

Ironically, I got shaft and strut work done to correct what was said to be a very critical misalignment issue. Now, when the engine is off the prop spins quite freely when in neutral.
__________________

jenglishsr is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 09:35 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012