Yanmar 2GM20F Starting Issues

[Drumroll30]

Don't forget to shut the seacock inlet before any repeated cranking.

[SailnParadise]

https://drive.google.com/file/d/13bA...ew?usp=sharing

Finally got to working on it again today. I think the air filter is missing. Am I correct?

[SailnParadise]

Originally Posted by SY Harmony

Dumb question, are you accidently trying to start in gear?

The shifter and throttle are very sticky. I have consulted the manual and have both is the specified positions.

Also about the seacock. I was unaware it needs to be closed for starting. Or was this just while servicing?

[SailnParadise]

I have also found these 2 wires either disconnected or corroded off. Any ideas as to their identification and proper place of connection?

https://drive.google.com/file/d/13cl...ew?usp=sharing

https://drive.google.com/file/d/13dz...ew?usp=sharing

[Cheechako]

Originally Posted by SailnParadise

https://drive.google.com/file/d/13bA...ew?usp=sharing

Finally got to working on it again today. I think the air filter is missing. Am I correct?

Mine had just a domed metal cover, nothing inside, but yeah, you are missing at least the cover.

[Cheechako]

Originally Posted by SailnParadise

The shifter and throttle are very sticky. I have consulted the manual and have both is the specified positions.

Also about the seacock. I was unaware it needs to be closed for starting. Or was this just while servicing?

Doesn't need to be closed to start, but too much cranking can create too much water in the muffler, backing up into the engine! OTOH, If the engine starts, it doesn't take much time if closed to destroy the water pump impellor.

Regarding shifting, just move the shifter forward and aft to see where it goes, then put it in the middle position.

[Cheechako]

Originally Posted by SailnParadise

I have also found these 2 wires either disconnected or corroded off. Any ideas as to their identification and proper place of connection?

https://drive.google.com/file/d/13cl...ew?usp=sharing

https://drive.google.com/file/d/13dz...ew?usp=sharing

That engine looks like it's been sunk. I'm very surprised it turns over at all.
Where are you at with that at this point? Will it turn over fast with a good battery or not?
I'd be very tempted to get the head off it and see what the cylinders look like, it may be rusty inside but still turning with a lot of resistance.

[SailnParadise]

Originally Posted by Cheechako

That engine looks like it's been sunk. I'm very surprised it turns over at all.
Where are you at with that at this point? Will it turn over fast with a good battery or not?
I'd be very tempted to get the head off it and see what the cylinders look like, it may be rusty inside but still turning with a lot of resistance.

It did turn with battery but it looks like the charge lamp terminal and ground terminal are corroded from the starter to the alternator. I'm not aware of it being sunk. The boat is in very good condition. It just seems there was some water ingress in the engine.

[SY Harmony]

See if it lights off on a sniff of ether

[SailnParadise]

Now power goes down to 1-2v when cranking

[SailnParadise]

https://imgur.com/a/msV0NDd
Anyone know what this is? seems to have a melted hose attached.

[SailnParadise]

Seems to right above the mixing elbow

[skipperpete]

That last photo is just a drain cock. You have a helluva lot of work ahead of you with that engine and the fact that there’s corrosion in the air intake is significant. I’m not surprised that you have electrical problems but you also have 2 potentially very destructive oil leaks in the unlikely event that you get that little yanmar started. You need professional help with this.
Maybe put your old MD2B in there instead of the 2GM

[Carl-T705]

Originally Posted by Cheechako

You need the starter to turn the engine fairly fast. But first:
How long since it ran? Could the fuel be mucky and old?

-Clean all the fuel filters including the one mounted on the engine. Leave filters as full of fresh fuel as you can. (depends on how many filters you have etc)

-With the new battery installed, crank the engine over, no more than maybe 15 seconds at a time, and crack open one of the 'fuel injector nuts' on the tubing going to the injectors. (if you dont know how to bleed this way look it up on line.) You want to crank the engine allowing fuel to spray at the injector nut until fresh fuel comes out and all bubbles stop..

There's just a lot of possible problems, too much to put in a post here. But if it turns over well, I would start there. You can also spray a little diesel in the air intake while someone cranks the engine, using a spray bottle. The engine should start for a second or two doing this.

Spraying diesel fuel in the air intake is not going to start a diesel engine, spraying starting fluid in will, provided you don't over spray it. Diesel fuel has to be injected into the cylinders at a specific time and at high pressure to ignite. If the filters have been changed or the engine has sat idle for extended periods the fuel system may have lost it prime. Check to make sure the emergency shut down is not closed, then, try a whiff of staring fluid in the air intake, then press the stater button.

[Carl-T705]

I just now saw your pictures, honestly, remove the engine and don't waste more time on that engine in the boat. There is too much corrosion in and on that engine to work on it it cramped quarters upside down. I assure you you , you will be time and frustration ahead to remove it. Those are popular engines in the US you may find a replacement at a fair price.