Yanmar20gm sat for a few years 2-3 wo being started. Got it started using starter fluid and it ran fine afterwards. Replaced batteries and engine would not start. Any help would be great as I am new to diesel engines.
Yanmar 20gm starting issue
- Thread starter 3GGG
- Start date
I am not a diesel expert but I did just buy the book and have read it recently. So you will probably get better advice than what I am about to give... but here is the link to the book so that this post is not a total loss.
My limited understanding from what I just read is that (assuming compression is okay) it is either starved for fuel (check filters and fuel lines) or the glow plugs are not getting hot (check voltage). If it is turning over without starting then voltage is not the problem. Are the glow plugs getting hot? If so then it is a fuel problem.
My limited understanding from what I just read is that (assuming compression is okay) it is either starved for fuel (check filters and fuel lines) or the glow plugs are not getting hot (check voltage). If it is turning over without starting then voltage is not the problem. Are the glow plugs getting hot? If so then it is a fuel problem.
Rgranger thanks for the quick reply! Thanks for tbe simple break down I appreciate it. Ordering book today.
I don't believe that model of Yanmar has glow plugs, it just uses compression to ignite the fuel. Make sure your fuel is clean (you can hook up a temporary tank with fresh fuel) and check the fuel delivery system as granger says. If you don't have a copy, here's the manual - you should familiarize yourself with the fuel system: https://sbo.sailboatowners.com/downloads/Yanmar_1GM-10L_2GM-F-L_3GM-D-F-L_3HM-F-L.pdf
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 21,845
The diesel engines on our boats really demand little to work.
Air, clean fuel, and compression.
You indicated you gave the engine starting fluid to get it to run. This is often done to facilitate a start, but it can mask problems.
You state “replaced batteries and now it won’t start“. Does this mean the starter motor is not turning over? Check your battery connections.
Next on the list is AIR. Make sure you have a clean air source. Nothing blocking the air intake ( like a rag).
Following the requirements list FUEL. Be fastidious about checking from the tank to the on engine filter that all hoses, lines, and connections are leak free, clean and provide clear flow of fuel. Clean filters.
I left COMPRESSION for last as you said the engine ran once. It is here you might consider talking with a diesel mechanic or at the least consult the book you are going to buy.
You had her running once. She’ll run again.
Air, clean fuel, and compression.
You indicated you gave the engine starting fluid to get it to run. This is often done to facilitate a start, but it can mask problems.
You state “replaced batteries and now it won’t start“. Does this mean the starter motor is not turning over? Check your battery connections.
Next on the list is AIR. Make sure you have a clean air source. Nothing blocking the air intake ( like a rag).
Following the requirements list FUEL. Be fastidious about checking from the tank to the on engine filter that all hoses, lines, and connections are leak free, clean and provide clear flow of fuel. Clean filters.
I left COMPRESSION for last as you said the engine ran once. It is here you might consider talking with a diesel mechanic or at the least consult the book you are going to buy.
You had her running once. She’ll run again.
I would like to know what else you fixed besides replacing the battery….
And what are the new symptoms….engine won’t turn over? Engine turns over, but never fires.?
This is also where I would throw in a caution about cranking the engine with the cooling water thru-hull open. Good way to cause hydro-lock and really mess up the engine. So, if the engine doesn’t start, I would close the thru hull while trouble shooting. Better to replace an impeller than doing an engine rebuild.
Greg
And what are the new symptoms….engine won’t turn over? Engine turns over, but never fires.?
This is also where I would throw in a caution about cranking the engine with the cooling water thru-hull open. Good way to cause hydro-lock and really mess up the engine. So, if the engine doesn’t start, I would close the thru hull while trouble shooting. Better to replace an impeller than doing an engine rebuild.
Greg
I went down last night and the engine cranked on second push. I let it run for 2 hrs and it ran fine the whole time.
Will see how it does the next time which will be a few days.
Did you change the fuel filter?: I haven't. I don't know when the previous owner did last. On the list for replacing
What's it do when you hit the start button? It was trying to turn over but never seemed to get enough compression to fire?
Where are you setting your throttle? I had it set to about 1/4 to 1/3 throttle
It is here you might consider talking with a diesel mechanic or at the least consult the book you are going to buy.
You had her running once. She’ll run again. : It was the diesel mechanic at the marina that got it running the first time.
Tally Ho: Thank you for the hydro-lock comment! I will look further into that.
Will see how it does the next time which will be a few days.
Did you change the fuel filter?: I haven't. I don't know when the previous owner did last. On the list for replacing
What's it do when you hit the start button? It was trying to turn over but never seemed to get enough compression to fire?
Where are you setting your throttle? I had it set to about 1/4 to 1/3 throttle
It is here you might consider talking with a diesel mechanic or at the least consult the book you are going to buy.
You had her running once. She’ll run again. : It was the diesel mechanic at the marina that got it running the first time.
Tally Ho: Thank you for the hydro-lock comment! I will look further into that.
This suggests it is a battery problem. Could be poor connections or could be the battery. Check and clean all the connections, including the mounting bolts. The starter is probably case grounded, thus the bolts are part of the circuit. Pay particular attention to the DC- cable from the engine to the DC- bus or battery. Poor connections or corroded wire will cause this symptom.
If you have tried to start it a lot, the battery may need charging.
Here's a photo from a friend's boat. He too was having trouble starting. Any guesses?
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 21,845
Good news about the start success.
With a charged battery and good connections to the starter, you should get a strong cranking of the starter motor to drive compression. If this is not the case, my first consideration is the battery. Second the wiring and connections between battery/starter switch/starter.
1/4 might be a bit rich. While all engines have their own peculiarities I tend to set the fuel at 1/8th or less. Just a wee bump above idle. When your engine starts, if you see a white puff of smoke that eventually disappears the start was too rich. The white smoke is unburnt fuel.
That you got it started again is great. May you have a long and joyful cruising history together.
With a charged battery and good connections to the starter, you should get a strong cranking of the starter motor to drive compression. If this is not the case, my first consideration is the battery. Second the wiring and connections between battery/starter switch/starter.
1/4 might be a bit rich. While all engines have their own peculiarities I tend to set the fuel at 1/8th or less. Just a wee bump above idle. When your engine starts, if you see a white puff of smoke that eventually disappears the start was too rich. The white smoke is unburnt fuel.
That you got it started again is great. May you have a long and joyful cruising history together.
Hmm... no idea!
My connectors and wiring looked good , at least what I could see. I suspect the new batteries I had didn't have quite the charge I needed. After a day on the trickle charger the engine started up on second attempt. That's my theory anyway.
OK. I will try 1/8 next time. I didn't notice any white smoke though on startup BUT I wasn't looking for it either.Good news about the start success.
With a charged battery and good connections to the starter, you should get a strong cranking of the starter motor to drive compression. If this is not the case, my first consideration is the battery. Second the wiring and connections between battery/starter switch/starter.
1/4 might be a bit rich. While all engines have their own peculiarities I tend to set the fuel at 1/8th or less. Just a wee bump above idle. When your engine starts, if you see a white puff of smoke that eventually disappears the start was too rich. The white smoke is unburnt fuel.
That you got it started again is great. May you have a long and joyful cruising history together.
Sailor Sue,
Good idea. I will try that. The batteries are new with a new trickle charger on them so they shouldnt be the issue. Definitely need to get my confidence in the engine increased.
Good idea. I will try that. The batteries are new with a new trickle charger on them so they shouldnt be the issue. Definitely need to get my confidence in the engine increased.
The 2GM needs to be at pretty much full throttle for starting. Reduce it to idle speed as soon as it fires up. It uses the heat generated by compression to start, so the cooler the engine and fuel are, the slower it is to start.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 21,845
Batttery charging and charging systems are a whole new field for the new boat owner/sailor.
Here is a link to some light reading about the subject.
Choose Your Battery Chargers Carefully
The Victron IP-65, IP67 are the best values in marine chargers under 30A.
marinehowto.com
@jssailem recommended you check the battery connections... That is sound advice. Let me share two different electric ghost stories..
1) I had installed brand new LED nav. lights on my sailboat at the end of the season. Come spring only one worked. I bought a new one... still didn't work.... I checked the voltage (should have done that first) at the LED and it was 13V until I tried to turn it on and then it dropped to only 9 volts... checked voltage at the battery and it was 13V... so... ripped all of the line back from the LED to the bus-bar. Still no joy... many curse words later I simply cleaned the connector at the battery terminal and everything started working as it should. Lesson learned the expensive way.
2) I used to own a Maycraft 19 center console.... The 115 Yamaha 2-stroke started doing this odd thing where sometimes I would get a dead switch when I tried to start it up. It was only every now and again but when it happened it would last a few hour (sometimes days) I tried every normal thing... changed the solenoid. Replaced the starter... replaced the switch.... Then brought out a mechanic who suggested I replace the starter, solenoid and switch...... then got another mechanic...he started down the same path but I told him what had already been done...after cleaning a few leads, it worked fine.... FOR ABOUT A WEEK... then dead switch while I was out on the water.... brought the mechanic back out and could not repeat the problem.... then this old timer at the dock says to me... it is the battery cable... I've seen it before.... if bet if you cut the insulation you will see "black copper" has creeped up under the insulation... Well that sounded crazy but I had tried everything else... changed the battery cable and all was good... when I cut the insulation on the old cable "black copper" had creeped up under the insulation.
So... clean all of your wire connectors before you start spending money on new parts.... you might get lucky.
1) I had installed brand new LED nav. lights on my sailboat at the end of the season. Come spring only one worked. I bought a new one... still didn't work.... I checked the voltage (should have done that first) at the LED and it was 13V until I tried to turn it on and then it dropped to only 9 volts... checked voltage at the battery and it was 13V... so... ripped all of the line back from the LED to the bus-bar. Still no joy... many curse words later I simply cleaned the connector at the battery terminal and everything started working as it should. Lesson learned the expensive way.
2) I used to own a Maycraft 19 center console.... The 115 Yamaha 2-stroke started doing this odd thing where sometimes I would get a dead switch when I tried to start it up. It was only every now and again but when it happened it would last a few hour (sometimes days) I tried every normal thing... changed the solenoid. Replaced the starter... replaced the switch.... Then brought out a mechanic who suggested I replace the starter, solenoid and switch...
... then got another mechanic...he started down the same path but I told him what had already been done...after cleaning a few leads, it worked fine.... FOR ABOUT A WEEK... then dead switch while I was out on the water.... brought the mechanic back out and could not repeat the problem.... then this old timer at the dock says to me... it is the battery cable... I've seen it before.... if bet if you cut the insulation you will see "black copper" has creeped up under the insulation... Well that sounded crazy but I had tried everything else... changed the battery cable and all was good... when I cut the insulation on the old cable "black copper" had creeped up under the insulation.So... clean all of your wire connectors before you start spending money on new parts.... you might get lucky.
Good in theory.
In practice, not so much. Trickle chargers, those that provide ~1a of charge current are designed to off set the normal self-discharge rate of about ~1a per day. If you do the math, they don't do much for recharging a battery.FLA batteries want a strong charge at 10% to 20% of their rated amphour capacity, in practice they do best with a 3 stage charger in the 15-20 a range. It is no coincidence that Victron makes 18a chargers.
