rintys1

Oct 4, 2014
11
hunter 27 st kitts
i have a 2008 yanmar 15hp have been having an on going problem with the engine.
Only gets to 2000rpms and black smoke comes out of exhaust.
Any help or advice as i have been trying to get fixed for a while.The engine has very few hrs of use.Thank you
 
Dec 1, 1999
2,391
Hunter 28.5 Chesapeake Bay
Make sure air clearner/silencer is clean and not blocked, but this sounds like a clogged mixing elbow issue to me.
 
Jan 4, 2006
7,297
Hunter 310 West Vancouver, B.C.
Only gets to 2000rpms and black smoke comes out of exhaust.
Further to warren's suggestions, check for;

- proper diameter and pitch of the propellor

- the prop is reasonably clean

- is the hull reasonably clean.

Black smoke at 2K RPM speaks of a problem (big or small) which requires immediate attention. This can cause other problems.

PS - what is your speed at 2K.
 
Jan 4, 2007
406
Hunter 30 Centerport
Make sure your prop and shaft run free. (Engine not running and transmission in neutral). You may have fishing line or something wrapped around the shaft in front of or behind the strut or next to the shaft log (where the shaft enters the bottom of the boat). Do check for a clean bottom and clean prop and then a clear mixing elbow. But a quick dive will let you know if there's a wrap.

Do check the simple stuff first.....
 
Oct 4, 2014
11
hunter 27 st kitts
thank you for your reply the boat will only go 2 to 3 knots and very little in reverse.The boat bottom and prop is clean.
 
Jan 4, 2006
7,297
Hunter 310 West Vancouver, B.C.
thank you for your reply the boat will only go 2 to 3 knots and very little in reverse.The boat bottom and prop is clean.
Sounds like a severe problem. Maybe not expensive or complex, but severe.

Couple of answers may help to solve the problem:

1. Has the smoke and no power been a problem since the first hour ?

2. What is the maximum RPM in neutral ?

3. Does the engine still smoke at high RPM in neutral ?

4. Is engine starting easy or hard ?

5. What is the diameter and pitch of the prop ?

6. How old is the fuel ?


As mentioned above posts, start with the simple stuff $$$ first and move up from there.

a) Check the air cleaner/silencer as per Warren. Rags, obstructions ?

b) Remove and check the interior of the mixing elbow.

c) to be continued ..............
 
Oct 4, 2014
11
hunter 27 st kitts
No it has gotten to this point all of a sudden.At the beginning of the issue in neutral it would go to high RPMs then it got to were even in neutral it would not get up in RPMs.2.5 RPMis max in drive and neutral.The engine starts easily but also seems to be skipping when i give it throttle.Thanks for all who are helping
 
Jan 4, 2006
7,297
Hunter 310 West Vancouver, B.C.
No it has gotten to this point all of a sudden.At the beginning of the issue in neutral it would go to high RPMs then it got to were even in neutral it would not get up in RPMs.2.5 RPMis max in drive and neutral.The engine starts easily but also seems to be skipping when i give it throttle.Thanks for all who are helping
The dirty (not nasty) picture below MAY be your problem but as you say, you have low engine hours so maybe not. We'll wait to hear your answers to questions a) and b) above and then on to a little more navel gazing.
 

Attachments

FredV

.
Oct 16, 2011
148
Hunter 37-cutter Philadelphia, PA
Found this after Google search for "diesel exhaust smoke": Black smoke is a sign of engine overload, a restricted air supply, or a malfunctioning injector. For some reason, excess unburned fuel is being blown out of the exhaust.

Hope it helps!
 
Oct 4, 2014
11
hunter 27 st kitts
Thank you all for your help.It was the mixing elbow confirmed yesterday.Can anyone recommend a Yanmar dealer i am located in St Kitts looking at probably Miami,Florida area.Checked neighboring islands no luck.
 
Dec 14, 2003
1,434
Hunter 34 Lake of Two Mountains, QC, Can
Mastry Engine Centre in St.petersburg is the main Yanmar distributor for Florida and the Caribbean. don't know if my info is up-to-date but their coordinates used to be 2801 Anvil St. North, St.petersburg, FL 33710, Tel: 727 522 9471.

Frank at Marine Pro of Central Florida might be able to help you. Coordinates are: 2150 W. King St., Cocoa, FL 32926. Tel 321 636 8950, Fax 321 638 3668 http://www.marinepro.us. He has helped me quite a bit.

Last but not least, Budget Marine in St.Marteen were able to get Yanmar parts for me very quickly a few years ago. Good luck