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Thread: Yanmar SB12 Starting Issues

  1. #1
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    Default Yanmar SB12 Starting Issues

    I understand though other internet sources that this forum has a number of member with experience with the Yanmar SB12 diesel engine. I have one of these and am having some difficulties.

    Before I dive into what is going on, can I get a confirmation that there is some expetise on the subject within the list members?

    I'll get back with all the details.

    Homer Shannon

  2. #2
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    Default Re: Yanmar SB12 Starting Issues

    I had starting issues with a Yanmar GM-10; local dealer said 99% of hard starts are due to owners loosening the wrong bolt on the filter when purging the system. He gave me (yes, gave) a gasket to put under the "non purge bolt" and the problem was solved. I hope this helps.
    Dave

  3. #3
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    Default Re: Yanmar SB12 Starting Issues

    Homer, you might as well just lay out the problem. Asking people if they are experts is notoriously unreliable due to the "Dunning-Kruger Effect".
    People who actually know a lot will tend to answer "Well, I know some stuff but I'm sure there are other people who know more". People who only know a little will tend to answer "Oh, yeah. I know all about those".
    (Personally, I'm OK with diesels and I've worked on a bunch, but mostly Volvo or old Ford Lehman.)
    Sometimes you've gotta leave the kibble out where the slow dogs can get some....
    ... Roy Blount, Jr.

  4. #4
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    Default Re: Yanmar SB12 Starting Issues

    OK. Here's the situation.

    I did my normal spring starting procedure; put in charged batteries, flush the bowel on the primary filter (though this time I removed it and inspected it), start engine. This has worked flawlessly for ten years. By the way, I see posts on this site saying the Yanmar SB12 is too rough, too heavy and underpowered. My opinion is that in ten seasons it has failed to run only three times, all due to getting air in fuel lines - which was quickly resolved, has never needed a real repair, runs smoothy enough, uses less than 1/3 gallon of fuel per hour, and pushes the boat to 5.5kn in most conditions. What more could you ask for more?

    The problem is that this year the engine did not start. Not even a burp. I figured I got air in lines after removing the primary fuel filter and fully bled the system. Still, no go. A shot of ether demonstrated that the engine will fire under compression but it will not start. I only used enough ether to fire on one or two rotations. I had no problems with the engine last summer, it was running when I pulled the boat for the season, and it was carefully put away for the winter.

    I suspected that the injection pump may not be working, but despite a significant deviation due to a misunderstanding of the device's operation, I am now 100% certain it is working, though I can't measure the fuel pressure. The lift pump is also working.

    At this point I'm thinking I have a bad injector (there is only one). I'm going to pull it out this weekend and see if I can get a look at its opertation. I called a local diesel mechanic but he did not have the equipment to test it.

    Interestingly, when I purchased the boat ten years ago, the former owner gave me the original injector, which he said was bad. (Why did he, and I, keep it? Who knows!) Anyway, his notes on the box state that it was replaced in 1994 when the engine was 16 years old. The engine is now 31 years old, making the replacement injector 15 years old. Hmmm.

    So my plan from here is to have a look at the injector and see if it is spraying. If not, I'll order a new one on Monday and probably get an injector pump plunger and barrel as well. The pump assembly costs around $250 but the plunger and barrel are the main wear componets and you can replace them for about $65. If these repairs don't fix the problem, I have no idea what to look for next.

    But I'm kind of thinking that a new injector is going to do the job.

    Fair winds, Homer

  5. #5
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    Default Re: Yanmar SB12 Starting Issues

    Are you getting fuel up to the injector? If you are, and the motor will not start with ether, then it could be the injector. Be sure you check the air intake and exhaust for blockage. Also be sure your compression release isn't sticking on somehow. Check your valve lash adjustment and head bolt torque also.

  6. #6
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    Default Re: Yanmar SB12 Starting Issues

    Thanks uncle http://en.wikipedia.org/wiki/Dunning...3Kruger_effect

    “ In the modern world the stupid are cocksure while the intelligent are full of doubt. ”

  7. #7
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    Default Re: Yanmar SB12 Starting Issues

    I’ll bet it is air in the pump…

    But -
    and I digress...

    Those fuel pumps can stick open and not pump. This can happen with non-use.
    To test, take the fuel line completely loose from the injector, loosen the end at the pump and rotate it clear of the injector and re-tighten the pump end. Open the compression release and crank the engine by hand for eight or ten revolutions. You should have a noticeable squirt.

    If not, the pump is not pumping. Before you go any further be certain that the pump has fuel and not air. Air is the most common problem. Confirm this (that the pump is full of fuel) and test again.

    If you have a noticeable squirt, remove the injector from the cylinder head and reconnect it to the fuel line and repeat the cranking procedure, the injector should spray fuel.
    (*Note there is a solid copper washer at the base of the injector, be certain it is in place when you reassemble).
    Check the condition of the spray; It should spray once for every two engine revolutions. If it is a dribble you have a bad injector. If it does nothing it is probably the pump as the injector will not do anything until it sees about 3000 psi.

    At this point you will need an expert with the proper tools to disassemble the pump, clean, inspect and repair it and reset the timing.

    Do not remove the pump... The fuel timing is controlled by the pump mounting and is the most critical part of this procedure and should be measured at the time of disassembly. The timing is controlled by a stacked gasket / shim arrangement under the pump base. You need at a minimum, a micrometer to check and set this.

    Really, at this point you need an expert. An expert will only cost a few hundred dollars while an amateur can cost you an engine.

  8. #8
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    Default Starting Issues - Resolved

    My instincts told me that sitting over the winter wouldn't result in a bad injector or injector pump. Turned out to be just bad filters. I replace both the primary and lift pump filters, re-bled the system and immediately got the good squishing shound of the injector as I turned the engine over by hand. It fired right up on the starter.

    As for Canoeyawl'ls comments on the fuel pump, I don't think replacing it is a job for an expert. The manual is very clear on how to do the timing. It does not look difficult but would be a major pain if you don't have good access to the back of the motor where the starter is. You have to remove the starter to see the timing marks.

    Fortunately, I did not have to do that operation.

    Homer

  9. #9
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    Default Re: Yanmar SB12 Starting Issues

    Pull the injector ,hook it back up to the high pressure fuel line, stick it IN a coffee can and crank the engine. If the injecter and injecter pump are working ,It will shoot fuel, with violence, into the coffee can. Be carefull of not using coffee can, PEOPLE can ,and have been "injected " with diesel'. This test is 'specialy good with one lungers .Don't sak me how I know that.

  10. #10
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    Default Re: Yanmar SB12 Starting Issues

    Oh,day late and a dollar short?

  11. #11
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    Default Re: Yanmar SB12 Starting Issues

    I might as well finish this thread with one more tidbit of information that may useful to some future SB12 owner.

    After getting the engine put back together and launching the boat I noticed that my power was down and the engine would not rev above an estimated 2200RPM. Top power is normally at 3000RPM.

    I knew this was related to the throttle (spindle) setting and governor as I could push the throttle at the engine and make the engine rev until I let go, then the governor would pull the engine speed back down. I had not messed with the governor, it's all internal and mysterious - almost nothing about it in the shop manual, so I correctly assumed that it was not the problem.

    The shop manual does describe the method of adjusting the linkage for correct idle and top speed. I followed these instructions carefully but got no improvement.

    After mulling it over with some guys at the club, it was agreed that somehow I needed more tension on the governor lever spring. We went and studied this thing and, low and behold, in addition to the hole in the lever arm for the spring that looks like the right place to connect the spring, there is a second hole further out on the arm. I reconnected the spring to this hole and now the engine runs perfectly right up to its top RPMs. Moving the spring on the arm provides more leverage and hence pushes harder against the governor that is trying to keep the RPMs down.

    All in all, a lot of fussing around for the sake of a couple of clogged filters. When you only use 20 gallons of fuel or so a year, you really don't expect the filters to clog up. But on the bright side, I know a hell of a lot more about how the injection system on this motor works now and I've picked up a spare spindle and needle assembly that I'll keep with my on-board spares. Just in case.

    Fair Winds, Homer Shannon

  12. #12
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    Default Re: Yanmar SB12 Starting Issues

    Hi Homer,

    I have been following your threads about the starting issues you had with your SB12, since I am a new owner of this glorious machine myself - in fact the exact same model. The engine is in a 1979 27' Bristol sailboat that we bought last year and had engine headaches all season. It started when we were looking at the boat, but failed on its way out the mooring after launch (and purchase!). After a couple dead end troubleshooting ventures, it ended up being the head gasket that needed to be replaced. After that replacement, it started on the first turn.

    After the head gasket replacement she ran us in and out of the harbor well enough for a couple months until after a long day rolling around on swells with the sails up, we were coming into a harbor farther down cape and she failed and would not start again. Before we bought the boat it had been sitting on land for a few years, we had not cleaned out the gas tank so I figured it was gunk that got kicked up and clogged the filters. I replaced both (we have a primary Racor R12 installed before the secondary filter), bleed the system and she was up and running again no problems. Then, coming into the mooring in October in high winds she failed again, again without even a hint that it might start again.

    Finally we had had enough and hauled the boat out, bringing her in under tow. I got it running again by changing primary filter and bleeding the system on land before winterizing. Just last week I was recommissioning the engine; she ran for a minute on the first turn after the whole winter, then died. I noticed a large amount of black soot on and near the front of the engine (belt/injector/high pressure metal fuel lines side). I wiped it off hoping that it was left over from the leaky head gasket, but I also noticed some duck tape on the exhaust hose about 2 feet up from muffler (which they conveniently placed right in front of the oil drain plug). I bleed the system, wiped off the soot, and she started again, running smoothly for 10 or so minutes. I put my hand in front of the duck tape and there didn't seem to be any exhaust coming out, and the engine room air stayed clean. The boats set to launch this week, and we have to bring her through woods hole passage to the slip. So we're crossing our fingers she doesn't die on us there.

    The point of the story is that I can't figure out why she keeps dying after starting up so well and running for a month or so. If there was a leak in the fuel lines letting air in I would have noticed a fuel leak. I took the whole tank out in the winter and cleaned it, so there is no more gunk and hopefully that will help. My only guess is after finding a missing o-ring on the deck fuel fill, water has gotten into the gas - but shouldn't I see water at the bottom of the primary filter??

    I am taking my chances that this time she won't die on me again, but if the story goes as its gone she will. Probably in the middle of the channel with a 4knt current.

    Many thanks for your thoughts,
    Victor

  13. #13
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    Default Re: Yanmar SB12 Starting Issues

    Victor, welcome aboard. I don't know if Homer is still around, and I'm not an expert. I did run an SB12 fior several years in a 26' yawl. Also burned up a head gasket. My problem was that the engine zinc hadn't been changed. This caused decay and blockage in the cooling system and the exhaust. Try taking the hose off the exhaust elbow, see if it is clogged with debris. If so, you should try to clear out all hoses and exhaust. Also check the head to see if the cooling passages are clogged, mine were solid. I found this engine to be very reliable and plenty strong.

  14. #14
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    Default Re: Yanmar SB12 Starting Issues

    Thanks for that! I have not yet changed the zinc, but just ordered one along with a gasket and will change it when it arrives. We had a mechanic come and take the head off to change the gasket; we didn't have the tools or experience to tighten it back up to the correct torque. I was there when he did it and he had the exhaust elbow off, and the passage for the raw water cooling flow was indeed clogged. We get a pretty good flow of water out the back of the boat now though, so it seems to be clear.

    I did note though, that when I first started it up last weekend, the first half bucket or so of water that came out the exhaust had lots of black in it - the exhaust smoke was a good color (i.e. not really any smoke) but the water was black and oily for while then became clear. There is a large plastic box that the exhaust and raw water outflow (they seem to be shared) attaches to before leaving the boat. Is this the muffler? I was thinking I might take the hoses off of this part to see how it looks. Do these mufflers (if thats what it is) need to be replaced?

    Many thanks for this and the encouraging words about the engine.

  15. #15
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    Default Re: Yanmar SB12 Starting Issues

    Inamist.
    As you probably know, Woods Hole is no place to lose power. Plan your tides accordingly and have your anchor ready.
    "If a man speaks at sea where no woman can hear, is he still wrong?"

  16. #16
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    Default Re: Yanmar SB12 Starting Issues

    Yes, that's a muffler. Mine didn't have one (loud!). My current boat does, but I don't know when they need changing. There are a couple of really good books on marine diesels. I think my favorite is "Troubleshooting Marine Diesels" (it's on board). One will help you understand your motor.

  17. #17
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    Default Re: Yanmar SB12 Starting Issues

    I do have a couple books and everything I know about diesel engines has come from them over the last year. I have 'Troubleshooting Marine Diesels' by Peter Compton as you suggested. I have actually found 'Marine Diesel Engines: Maintenance, Troubleshooting, and Repair' by Nigel Calder a more comprehensive source. Being inexperienced, it was nice to have multiple references that explain things differently.

    Still, its nice to be able to ask questions of people with exactly the same model engine. Which is hard to do of a book.

    I'll hit the hole at slack tide with an anchor ready - I am coming down the stretch of Buzz Bay so I should have a good feel for how its going to behave before I get there.

    Many thanks again.

  18. #18
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    Default Re: Yanmar SB12 Starting Issues

    I think you call them 'lift mufflers' over there. The black stuff in the initial outflow is badly burned fuel, which is normal on start up on this type of engine. They tend to over fuel until the RPM build up. I expect this hangs around the muffler before being blown out.
    Homer, the guy passing on the old injector was being nice, changing the nozzle would bring it up to new, so a good spare at less than buying the whole unit. BTW, water in pumps and injectors is a real killer, so glad it wasn't that.

    BTW, interesting thread..
    Last edited by andrewe; 04-28-2011 at 01:22 PM.

  19. #19
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    Default Re: Yanmar SB12 Starting Issues

    Hi All,

    I wanted to follow up with this thread rather than starting a new one, since I have gotten some great feedback from many of you. To recap: I am a new owner of a yanmar SB12 (1979 single cylinder diesel) that keeps dyeing. She has been running since May with probably 3-4 hours of run time total this season, but it just died again while bringing us through Woods Hole this weekend. This recent death is part of a pattern; she dies, i bleed the system (there are always air bubbles that come out), then she runs again for another month or so w/o problems until she dies again.

    I think the issue with the engine is almost certainly air in the system. But it must be a slow air leak. Have any of you dealt this this before?

    My question now is what to do? I could replace everything I guess, including the metal and rubber fuel lines, fuel filter housing, copper washers, ext... but I would rather not have to do that if there is only a single air leak somewhere. There was a note scratched onto a manual from the previous owner that sais "replace metal lines." I didn't know what that meant so cleverly ignored it, but am beginning to fear it might be related. I am now assuming by "metal lines" he means the high pressure lines from the fuel pump to the injector, then the return line from the injector to the secondary filter - which are made of metal, the rest are rubber.

    Is there a common leaky area in fuel systems? Perhaps around fuel filter housings?

    Has anyone had problems with their "metal" or high pressure fuel lines before?

    Is there a way to find a slow air leak?

    Many thanks!

  20. #20
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    Default Re: Yanmar SB12 Starting Issues

    The metal lines you refer to are pressurized. Any leaks there should show as fuel escaping. If you are getting air in the system it is probably getting in before your injector pump. I'm not a mechanic, but I believe that the injector pump is the bit that can't handle any air. Some more info would help. External fuel pump? Fuel filter? I once did a repair on a diesel with a small leak in the fuel tank's standpipe. When the fuel level dropped enough - air in the line.
    Schooner captains love to get blown offshore!

  21. #21
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    Default Re: Yanmar SB12 Starting Issues

    No external fuel pump, but 2 fuel filters - a primary and a secondary. The primary has a fuel water separator and drain screw at the bottom. The secondary is much finer filter and attached to the engine itself. The bubbles largely come out the rubber line running from the primary to the secondary, but I can't find anything wrong with the primary filter.

    What you mention about the standpipe is interesting, my fuel was at about 1/4 tank and we motor sailed for about 30 min with some heeling (trying to charge up the batteries).. i suppose its possible while we were heeling all the gas moved to the side of the tank opposite from the standpipe and it sucked air.

  22. #22
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    Default Re: Yanmar SB12 Starting Issues

    Sounds like air is entering your system before your primary filter. With no external pump, how are you pressurizing the primary filter to bleed its fuel outlet? Do you have a bleed screw on the filter? Your primary filter might be able to tolerate a bit of air before before sending it off to your engine. Maybe an hour or 3 of runtime worth.

    I mentioned the standpipe because I went through a whole lot of frustration before even thinking of looking at it. There should be a bit of space between the bottom of the standpipe and the bottom of the tank to give sediment and water a place to settle without immediately getting sucked out of the tank. Running heeled with a 1/4 full tank of diesel sloshing around - you could be momentarily uncovering the bottom of the standpipe. If you have no luck finding a leak between the tank and the filter you might try adding a bit of fuel to the tank.

    Where are all of the Forum mechanics? This poor guy is getting advice from somebody who shouldn't be allowed near an engine, and wishes he wasn't!
    Schooner captains love to get blown offshore!

  23. #23
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    Default Re: Yanmar SB12 Starting Issues

    I spent some time reviewing the fuel system last night, and was wrong about the external fuel pump. There is a mechanical pump with a priming bulb before the secondary filter, then an injector pump after the secondary filter that pressurizes the injector metal line. I use the priming bulb on the mechanical pump to bleed the secondary filter.

    The primary filter I actually bleed using an old bulb and some hosing I took off a gas tank from an outboard gas motor (the big black ones on the hose between your red gas tank and outboard motor). What I do is unhook the fuel line after the primary filter (that leads to the secondary) and hook in my old hosing and bulb... give it 5-10 sqeezes to pull fuel from the tank, through the primary filter and into an old water bottle, then hook the fuel line back in and bleed the secondary filter. Its hard to tell if there is any air coming out since there is so much fuel being bleed through. Again, the obvious air is coming from the secondary filter.

    One thought I had was the copper washers that secure each bleed screw (or banjo screw i guess). I have never replaced them. Has anyone had air leaks due to old copper washers?

  24. #24
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    Default Re: Yanmar SB12 Starting Issues

    It sounds like you're bleeding your system by sucking the air out. I've never heard of this being a proper method of bleeding. I don't think it's contributing to the problem, but maybe making it harder to diagnose. I don't think it's a good idea to remove a fuel line to bleed either.

    The banjos are on the pressure side of the system. leaks there should not be able to introduce air into the system. I'd recommend permanently installing an electric fuel pump between the tank and the primary filter. Any leaks after this pump will be fuel getting out, not air getting in. You won't have to disconnect anything to bleed, and you will narrow down the possible air leaks to a couple of hose clamps and the fittings on your tank.

    Where is the rest of the Forum on this one? Somebody please chime in and call me an idiot before this poor guy follows my advice. This is the first time I've seen an exchange go this long with only one responder.

    Does everybody have me on ignore?
    Schooner captains love to get blown offshore!

  25. #25
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    Default Re: Yanmar SB12 Starting Issues

    Copper washers can be annealed and recycled simply by heating them red hot with a propane torch and quenching in water. Hang on a screwdriver or coathanger and ALWAYS anneal the copper injector washer every time the injector is disturbed.

    Cheers, Dumah,
    Halifax, NS
    Duct tape can't fix stupid but it will muffle the sound

  26. #26
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    Default Re: Yanmar SB12 Starting Issues

    I've been keeping quiet because I've seen nothing to disagree with. And indeed, if you can find a way to temporarily pressurize the fuel line from the tank on down, diesel will ooze out somewhere and show you where the problem is. What sort of fuel tank do you have -- is there a vent you can pump air into (assuming the fill cap is airtight)? It wouldn't take much pressure to run such a test. And yes, the copper washers should not ever be reused unless you first anneal them.

  27. #27
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    Default Re: Yanmar SB12 Starting Issues

    I like the idea of providing 'back pressure' from the fuel tank - it does have a vent and the fill cap should be airtight. I went over the hoses today with a clean paper towel and went motoring for about a 20 min and checked everything for evidence of a leak after. Didn't see anything really on the lines or filters. I did see though a small puddle of fuel in an area where I cant really imagine how the fuel got there, and not even any moisture on the lines around it. That really puzzled me.

    I wanted to add an idea here thats growing on me. Before she died last weekend I was motor sailing for a while with a decent heel. The tank was only about 1/4 full... so I am thinking maybe the fuel all went to one side of the tank while we were sailing and it sucked some air. The more I think about it there was a huge amount of air that come out of the secondary filter before a flow of bubble-less fuel when I bleed it to get it going again, suggesting something more substantial than a small leak.

    What is also puzzling however, is that in my hurry to get the engine going again (we were not in a really safe place) I only bleed the primary and secondary filters - not the high pressure lines directly from the injector, yet she started on the first or second turn.

    I think I am going to just buy new copper washers, can you get them at an auto supply store?

    thanks again everyone.

  28. #28
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    Default Re: Yanmar SB12 Starting Issues

    After fixing my SB12 two years ago, it ran perfectly until two weekends ago when we sailed off our mooring, which we rarely do due to the heavy current of the Merrimack River, and I forgot to turn on the fuel cock later in the day when we needed to motor back up river against the current. We managed to sail to a mooring and hung on there until I bled the system. The following week I had to bleed it again but it's OK now. I thought while it was fresh in mind I'd post a note on how to bleed the thing. It's actually really easy.

    After opening the fuel cock (!), loosen the return line on the top of the on-board fuel filter. Using the lift pump of the bottom of the on-board filter, pump until you get fuel out of the loosened return line. When you get steady fuel, no air, tighten the fuel line bolt. Note: I have a bulb in-line on my fuel line downstream of my filters and a couple of squishes on that will do what fifty strokes of the fuel lifter will do.

    Next, using a 19mm wrench, break open the large nut on the fuel line at the injector. Once broken free, snug it momentary. An assistant at this point is a big help.

    Open the compression release on the engine and have an assistant turn the engine over with the starter motor. While turning over, open the nut on the injector slightly. Very quickly fuel will begin to emerge. When it does, tighten the nut back down.

    Now, with the compression release open, turn the engine over by hand. You should hear a small but distinct 'squishing' sound each time the engine goes through TDC on the compression stroke. If you hear this, it's going to run. If you don't, repeat the step before.

    Release the compression lever and try starting the engine. If you got the squishing noise, odds are it will run. Shut down the engine and make sure both nuts you loosened are good and tight - but don't strip the fuel filter. That thing is made out of very soft white metal.

    With practice and a set of metric tools, this process takes less than five minutes.

  29. #29

    Default Re: Yanmar SB12 Starting Issues

    This thread has become a good resource for YSB-12 owners so I wanted to add some comments to it and ask a question that others might be able to answer.

    In the summer of 2016 we had another air leak issue that lead to our engine quitting again. This time it happened in the Cape Cod Canal, right at the Borne Bridge and just as the railroad bridge came down. Of course! We pulled out the jib and used the Buzzard’s Bay southwesterly to hold in the current until a tow boat came along. They took us to Onset, where we anchored for the night, and in the morning I bled the engine and it went back to working fine.

    This spring, among other projects, I replaced a bunch of my copper banjo washers with new, soft washers. This year we had NO air line / injector problems. I think reusing the old, hardened washers (which I regularly did) was the root cause of most of my issues. You can purchase copper washers from Grainger for short money, but getting the right size is a problem. I’ve ordered them from Yanmar suppliers before and they were always wrong. Because the Grainger ones were cheap, I ordered about every size they have but there are still a couple on the engine that I don’t have replacements for – these I’ve annealed. Can anyone explain the nomenclature for the sizing of these things?

    I do seem to have a new problem this year, though. I am getting engine oil in my bilge water – not a lot but enough to make a mess and put oil in my bilge pump discharge. The engine is not using an excessive amount of oil and there is no obvious leaking. I have found one loose oil pan bolt, which I’ve tightened, but after the boat was pulled for the season, so I can’t confirm that this fixed anything. I tend to doubt that one loose bolt would make the oil pan gasket leak, but who knows. Maybe it would. There is no obvious leaking around the oil filter knob or anywhere else. Given that it is difficult to fully examine the system for leaks while underway, it may be that the leaking only happens at higher RPM and I just can’t observe it while the engine is idling or shut down. Any thoughts?

    In another post last year I described how I was going to repair my motor mounts. The lag bolts had completely stripped the wood of the motor stringers, so there was no way to secure the mounts. Over the winter I drilled out the stringers and sunk 1 ¾” x 3/8” stainless bolts into 1” x 1” holes and epoxied them in. I then placed the motor mounts over these and torqued them down with double nuts. This has worked very well and nothing loosened up at all over the sailing season. The only issue is that replacing the rear motor mounts will be a big hassle. I’ll have to disconnect the prop shaft and lift the whole engine off the mounts, replace the mounts, then put the engine back in place. The good news is that the rear motor mounts wear much more slowly than the front ones, which can still be easily replaced. I suspect the current motor mounts, which are new, will outlast my ownership of the boat (and possibly me, too!)

  30. #30
    Join Date
    Jun 2003
    Location
    Central Coast, Ca
    Posts
    21,386

    Default Re: Yanmar SB12 Starting Issues

    Copper washers come in many sizes...
    Most basic will be metric or English, (much of the Japanese stuff is often British Straight Pipe and may have a custom sized washer but they are readily available).
    A google search for "copper washers for banjo fittings" should give about a million choices. Amazon has an assortment like this for about $12...




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