I have a Yanmar 2GM20F on my 87H285. In the summer, this engine starts almost instantly -- she never takes more than one second of cranking. Before cranking, I advance the throttle to full, back to idle, and then set it at about 1/4 throttle for starting. But, in the cooler weather of fall (upper Chesapeake Bay), it's a different story. She cranks and cranks, sometimes catching a little, sometime with nothing. To go easy on the starter motor, I never crank for more than 10 seconds (and I keep the water inlet closed during all of this to avoid sucking sea water up the exhaust). I even try opening the compression levers and cranking her that way to get things stirred up. Even when I try having crew close the levers while cranking, she sputters that way, too. Eventually, she will start. It just takes a while. Are there any secrets out there I'm not aware of (excluding ether, which I don't believe in using). Should the throttle be open more or less? Eric Lorgus s/v Explorer 87H285
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Doug
Hair dryer in the air intake
I hear many people say that a hair dryer (or 12 volt heater, if not at shore power) blowing into your breater will decrease cranking time. They even make a 12 volt heat blower that you can attach to the intake for regular use. Doug
I hear many people say that a hair dryer (or 12 volt heater, if not at shore power) blowing into your breater will decrease cranking time. They even make a 12 volt heat blower that you can attach to the intake for regular use. Doug
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Randy
More glowplug
Have you tried using the glowplugs for an extra length of time? This helps to heat things up inside each cylinder, and will reduce cranking time. I often use this technique to start my diesel car...a little extra glow plug in cold weather, and up to two minutes in sub-zero conditions. Randy
Have you tried using the glowplugs for an extra length of time? This helps to heat things up inside each cylinder, and will reduce cranking time. I often use this technique to start my diesel car...a little extra glow plug in cold weather, and up to two minutes in sub-zero conditions. Randy
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Gordon Torresen
Cold starting
The Yanmar engines are designed to start with the throttle control at idle. The governor sets the proper amount of fuel for starting. You may have noticed (in warmer weather) that the engine starts and seems to slow down promptly after it starts. You are correct in staying away from ether. One shot of ether could crack a piston. If ether EVER has been used, you may have the answer to your starting problem. You will get a noticable decrease in compression that is a prime requisite for starting. All the other things must be in order. The batteries must be good and fully charged, The cable connectors must be clean, the cables must be good, the starter motor must be in top working order, the starter solenoid must make good contact, the engine oil must be of the proper viscosity. All these things are affected by temperature. Electrical resistance and oil viscosity (including that on the starter bearings) go up ans the temperature goes down. You might also stay on the starter button longer, after you are sure that the problem is not elsewhere. Thirty seconds of cranking will do no harm.
The Yanmar engines are designed to start with the throttle control at idle. The governor sets the proper amount of fuel for starting. You may have noticed (in warmer weather) that the engine starts and seems to slow down promptly after it starts. You are correct in staying away from ether. One shot of ether could crack a piston. If ether EVER has been used, you may have the answer to your starting problem. You will get a noticable decrease in compression that is a prime requisite for starting. All the other things must be in order. The batteries must be good and fully charged, The cable connectors must be clean, the cables must be good, the starter motor must be in top working order, the starter solenoid must make good contact, the engine oil must be of the proper viscosity. All these things are affected by temperature. Electrical resistance and oil viscosity (including that on the starter bearings) go up ans the temperature goes down. You might also stay on the starter button longer, after you are sure that the problem is not elsewhere. Thirty seconds of cranking will do no harm.
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Tom Senator
Randy, not all deisels have Glow plugs.
I have an older Yanmar (2QM15) -- that has problems starting in cold weather, and sometimes during the summer, when it hasn't been started in a while. I would love to have glow plugs but I don't, so that is not an option. But once that engine gets started it runs great ! and its over 20 years old. I think the Yanmars are great marine engines, but I have a feeling they have a history of hard starting, especially when not started for a while and cold (no its not the starter or the battery -- I have PLENTY of cranking speed)......maybe there is something to the fuel pump and *really* critical adjustment needed there ?
I have an older Yanmar (2QM15) -- that has problems starting in cold weather, and sometimes during the summer, when it hasn't been started in a while. I would love to have glow plugs but I don't, so that is not an option. But once that engine gets started it runs great ! and its over 20 years old. I think the Yanmars are great marine engines, but I have a feeling they have a history of hard starting, especially when not started for a while and cold (no its not the starter or the battery -- I have PLENTY of cranking speed)......maybe there is something to the fuel pump and *really* critical adjustment needed there ?
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Eric Lorgus
Thanks, more info & no glow plugs
Thanks Gordon. Next time I'll try cranking with throttle at idle. Oil viscosity is a possibility. I use what my Yanmar Service Manual says to, 30 weight, not a multi-viscosity. I've heard so many arguments about which is better that I've stayed with Yanmar's specs. The Yanmar 2GM20F does not have glow plugs. It does have compression levers which when released allow the engine to be cranked without compression. With the compression levers open, cranking the engine produces a whirr, as it really spins. I will always give the engine a whirr when cold before making serious attempts to start. Eric Lorgus s/v Explorer 87H285
Thanks Gordon. Next time I'll try cranking with throttle at idle. Oil viscosity is a possibility. I use what my Yanmar Service Manual says to, 30 weight, not a multi-viscosity. I've heard so many arguments about which is better that I've stayed with Yanmar's specs. The Yanmar 2GM20F does not have glow plugs. It does have compression levers which when released allow the engine to be cranked without compression. With the compression levers open, cranking the engine produces a whirr, as it really spins. I will always give the engine a whirr when cold before making serious attempts to start. Eric Lorgus s/v Explorer 87H285
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Garry Elmer
Cold Starting YANMAR
Crank it a bit to get the oil circulating and one tiny shot of ether down the intake. I've started engines with WD40 also. Everyone says horrible things about starting with ether but why do they use ether on the big diesels? Our YANMAR 2QM is 20 years old. I treated it to new injectors and that helped hard starting quite a bit but when it's cold a shot of ether still does the trick.
Crank it a bit to get the oil circulating and one tiny shot of ether down the intake. I've started engines with WD40 also. Everyone says horrible things about starting with ether but why do they use ether on the big diesels? Our YANMAR 2QM is 20 years old. I treated it to new injectors and that helped hard starting quite a bit but when it's cold a shot of ether still does the trick.
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Gordon Torresen
Oil viscosity
The information in your service manual about the oil to use is now updated. Yanmar is recommending 15W40 oil for all the small diesels. There is no way that all the manuals can be updated other than the updating the manual owners. The change came about because of newer technology in the oil blending industry. Cranking the engine with the compression releases open does let the cranking RPM increase greatly but you must remember that the injectors are squirting all the while, unless you have the stop cable pulled. You don't want to crank too long before tripping the release levers.
The information in your service manual about the oil to use is now updated. Yanmar is recommending 15W40 oil for all the small diesels. There is no way that all the manuals can be updated other than the updating the manual owners. The change came about because of newer technology in the oil blending industry. Cranking the engine with the compression releases open does let the cranking RPM increase greatly but you must remember that the injectors are squirting all the while, unless you have the stop cable pulled. You don't want to crank too long before tripping the release levers.
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