Logo
Results 1 to 14 of 14
  1. #1

    Default Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    Recently got this old boat, a 1981 Santana 3030. Is not the original engine. At first all fine. Clear exhaust. 3300 rpm. Now exhaust water is dirty/dark. Max rpms 2400. Pulled off mixer elbow and it is clean except for soot. Found some diesel fuel on the mixer elbow gasket. Is not using oil. Is not smoking.
    I am stumped.

  2. #2

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    Quote Originally Posted by Jim Oursler View Post
    Recently got this old boat, a 1981 Santana 3030. Is not the original engine. At first all fine. Clear exhaust. 3300 rpm. Now exhaust water is dirty/dark. Max rpms 2400. Pulled off mixer elbow and it is clean except for soot. Found some diesel fuel on the mixer elbow gasket. Is not using oil. Is not smoking.
    I am stumped.
    Am trying to attach photo (not attached, but you can email me for it [email protected]) of dark water that I collected directly from exhaust. Does not run rough. Bottom painted and prop cleaned about 30 days ago. Impeller replaced and was not deteriorated. Kept in freshwater. This boat had a broken mast... took the yard longer than normal to sleeve (about 2 months), so it has just been sitting at the dock. Every couple of weeks I would run it, first cranking without starting to distribute oil, then starting, running for a few minutes at low speed, then high speed in gear for 5-10 minutes as I know the engine needs a load for proper maintenance. Right now this is a major source of lake pollution. I always look at exhaust after starting to assure water flow, which is why I know it went from clear to dark/dirty. Put a 1/2 gallon of exhaust water in a bucket and photograhed it. Very little oil on top. Was going to run for an hour tonight, but afteer 10 minutes water temp alarm went off.

  3. #3

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    Quote Originally Posted by Jim Oursler View Post
    Am trying to attach photo (not attached, but you can email me for it [email protected]) of dark water that I collected directly from exhaust. Does not run rough. Bottom painted and prop cleaned about 30 days ago. Impeller replaced and was not deteriorated. Kept in freshwater. This boat had a broken mast... took the yard longer than normal to sleeve (about 2 months), so it has just been sitting at the dock. Every couple of weeks I would run it, first cranking without starting to distribute oil, then starting, running for a few minutes at low speed, then high speed in gear for 5-10 minutes as I know the engine needs a load for proper maintenance. Right now this is a major source of lake pollution. I always look at exhaust after starting to assure water flow, which is why I know it went from clear to dark/dirty. Put a 1/2 gallon of exhaust water in a bucket and photograhed it. Very little oil on top. Was going to run for an hour tonight, but afteer 10 minutes water temp alarm went off.
    No water in the oil. Here is link to page with photo of exhause water. http://forums.sailboatowners.com/ind...55/#QuickReply

  4. #4

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    Quote Originally Posted by Jim Oursler View Post
    No water in the oil. Here is link to page with photo of exhause water. http://forums.sailboatowners.com/ind...55/#QuickReply
    Had the fuel injector checked. A-OK. Now to look for the two fuel filters.

  5. #5

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    to attach, use advanced editor.

    Sounds like a fuel delivery issue.
    If I recall this engine can be gravity fed or may use lift pump; either mechanical or electric. Which method is in use?

    If you can use a different fuel source and fresh fuel you should be able to eliminate contamination as part of this.

    FWIW; 2 months on the hard should have been a non issue for this engine. Many sit 6-9 months with no ill effects.

  6. #6

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    Quote Originally Posted by waynebrown View Post
    to attach, use advanced editor.

    Sounds like a fuel delivery issue.
    If I recall this engine can be gravity fed or may use lift pump; either mechanical or electric. Which method is in use?

    If you can use a different fuel source and fresh fuel you should be able to eliminate contamination as part of this.

    FWIW; 2 months on the hard should have been a non issue for this engine. Many sit 6-9 months with no ill effects.
    I am going to dump the whole 12 gallons of diesel at a friendly auto repair shop. Will be a few days before I have an update. Will check into status of fuel delivery. Will replace the one, 1, fuel filter.
    Thanks for the help.

  7. #7

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    Quote Originally Posted by Jim Oursler View Post
    I am going to dump the whole 12 gallons of diesel at a friendly auto repair shop. Will be a few days before I have an update. Will check into status of fuel delivery. Will replace the one, 1, fuel filter.
    Thanks for the help.
    Replaced fuel filter (only one on this engine and none in line). Replaced diesel fuel and cleaned tank. Same problem. Removed remains of air filter. Max RPMs around 2600. Black sludge coming out with cooling water from exhauset. Removed oil filler cap and can discern noticeable air pulsing, compression being blown past the rings. Should I tear this down, or get a re-built engine?

  8. #8

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    that's a choice your budget pain threshold will have to make.

  9. #9

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    May have discovered the problem. While once again checking the mixing elbow, I noticed that the inside of the exhaust hose is blocking 20-25% of exhaust. Will get new hose tomorrow. Standby.

  10. #10

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    May have discovered the problem. While once again checking the mixing elbow,which looks almost new, I noticed that the inside of the exhaust hose is blocking 20-25% of exhaust. Will hopefully get new hose tomorrow. Standby.

  11. #11
    Join Date
    Apr 2016
    Location
    barnegat NJ
    Posts
    2,707

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    wer'e still standing

  12. #12

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    Quote Originally Posted by johnnygjr View Post
    wer'e still standing
    Didn't get the hose installed last night. Maybe tonite.
    Jim

  13. #13

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    well now you are just torturing us.

  14. #14

    Default Re: Yanmar 1GM10 Exhaust Water very dark and peak 2400 rpms

    Quote Originally Posted by waynebrown View Post
    well now you are just torturing us.
    I checked the mixing elbow again. After replacing exhaust hose, cleaning fuel filter ( was only the one on the engine) and replacing all diesel, still 2400-2500 RPM with black sludge out the exhaust. Good water flow out. REplaced impeller a few months ago and again visually inspected it. Ran tonight for 10 minutes at 2400 RPM, no overheat, but a trace of black smoke. Expect it to be the rings allowing blowby and black exhaust water and some black smoke. Will call diesel mechanic cause I don't want to tear into the engine.

Similar Threads

  1. Yanmar 1gm10 steam in exhaust
    By Marek in forum Yanmar
    Replies: 4
    Last Post: 06-12-2016, 09:59 AM
  2. Yanmar 1GM10
    By KJackson in forum Yanmar
    Replies: 14
    Last Post: 02-08-2010, 03:16 AM
  3. Yanmar 1gm10 leaking oil from exhaust port stud bolt
    By adambowenfsmailnet in forum Yanmar
    Replies: 0
    Last Post: 01-27-2010, 07:06 PM
  4. Replies: 4
    Last Post: 05-10-2008, 09:50 PM
  5. Yanmar 1GM10
    By Dougie Muir in forum Yanmar
    Replies: 1
    Last Post: 05-01-2006, 12:31 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •