Yanmar Diesel dead!?

[RW Sailor]

Hello again,
Sorry if that question was here before, but I couldn't find anything that really hit it...
I had some trouble with my 12 hp 1 cylinder Yanmar Diesel before and just when I thought it was working it died...
So: I was sailing all day yesterday, motoring in the morning (10am) and tried to start up the engine again around 7pm (constant sailing in between) and as I turned the ignition key NOTHING happened. I've had the starter failing before or just not quite kicking the engine, but there was nothing.
Now I have checked the solenoid (not sure if the spelling is right) there is nothing between the poles either - this is where I used to be able to just jump the engine and start it right up, but no sparks, nothing.
If I test the plus pole on the Solenoid and ground there is a current though, so there must be power, right?
So... what could it be?!
I was already towed into a Marina and am waiting for the mechanic tomorrow morning but it might help to save some...$$$... thanks for all the advice!
Manuel

[Custom30]

There is a decompression lever on the top of the engine, did you try releasing the compression to turn it over? Sometimes that is enough to get it moving again if the starter is weak or the battery is low.

On my boat, it is a contortion act to do this by myself.



'

[RW Sailor]

Originally Posted by Custom30

There is a decompression lever on the top of the engine, did you try releasing the compression to turn it over? Sometimes that is enough to get it moving again if the starter is weak or the battery is low.

On my boat, it is a contortion act to do this by myself.



'

Good thought, unfortunately not it though... just tried (again), turned over a bit but nothing...
Unfortunately I also don't have the handle to manually start/test it... :-(

[YankeePSC34]

Is the battery OK?

[roverhi]

Have you checked the ground connections. Most starter problems that aren't fatal are a ground wire that has corroded or come loose. Just checking for security is not enough, you need to loosen the connection and retighten. In your case, sounds like the solenoid is not working. If you have jumper cables, go direct from the battery to the positive pole on the starter. If you have juice in the battery, that will get the starter spinning. Also tapping the solenoid with a hammer or other blunt instrument may free up stuck innards.

[Badsanta]

How old is the battery. How much elec did you use while sailing. How do you charge your battery? you may have some juce in the battery but not enough to start it. Also fix what ever it is so you dont have to short out your starter. Time for a electric book.

[RW Sailor]

So the batteries are both topped up (solar) but that's not the problem (from what I see)
I think it's gonna be a loose cable somewhere around, only have to track it down or the solenoid or even the starter itself... something along the way died and now in about an hour I have the mechanic come on to track it down... I had to give up last night after a full day of trying to figure it out...

[SeaKing]

I had to replace an 18 foot long ground cable on one of my engines just two weeks ago. THe old cable would crumble when bent.

[Badsanta]

Tell us what the mechanic found

[RW Sailor]

Will let you all know - unfortunately he won't comebefore the 22nd, seems to be busy times in Annapolis at the moment.
And I couldn't find anything else. Kinda stuck on a dead end.
If I bridge on the Solenoid the starter turns but doesn't connect to the engine. Starting from Ignition the starter klicks and stops. And the engine is stuck, even if pulling the decompression. The Mechanics suspicion on the phone was water in the cylinder - apparently quite common on this Diesel and about 3300 Dollars to fix (PANIC)
The thing that annoys me most about is is having a boat and not being able to sail it. And I have to leave for 3 months the week after the mecanic shows up... bad timing...

[Badsanta]

If it is water I would pullout the injector and try to crank it to get the water out. If you just let it sit you really will have a problem. Hope its not .

[RW Sailor]

but would all the symptons described above work for water in the engine? It started several times and kept running for about 5 minutes before it completely stopped... I keep reading and searching but can't find anything that makes sense to me

[Badsanta]

When it stoped for the last time was it running or had you been cranking it and then it stoped and now wont turn over?

[foggysail]

I had a 12HP (Yanmar???) POS in my old 30' Hunter. Yours may not be the same, mine had raw water cooling and the piston stroke was horizontal. I had to redesign the motor mounts to minimize vibration.

Anyway, my POS failed, saltwater got into the combustion chamber either via the head gasket or through the corroded cast iron. I soaked the piston with kerosine for weeks, could not free the piston. The guy I gave the engine to hammered the piston to pieces in order to clear the cylinder walls. Think he eventually junked it.

Suggest that you NOT spend money to repair especially if it is raw water cooled. Consider searching for a good replacement that will physically fit where teh current engine resides. Most likely you will need new motor mounts, and a new shaft.

Word of caution with motor mounts! These things are not like screw drivers which are all essentially the same and found on everybody's shelf. They are engineered to specific operating conditions. For example, the boat's forward/reverse thrust is subjected to the mounts. So a mount with an adjustable height should be avoided because the horizontal thrust vector applied to the mount varies with the height of which the thrust vector is applied. Better to shim under the mounts for height adjustments.

The mounts must be designed to meet vertical thrusts along with horizontal thrusts. They are also designed for specific load frequencies (vibrations). And it gets better! They have their own resonances and you want them to be as low frequencies as possible.

Foggy

[Liam Wald]

Many years ago (1980's) I had a Yanmar 12hp single cylinder. I found out after it died that this model (due to the extreme vibration caused by the imbalance of one cylinder) requires frequent attention to the head bolt torque, They seem to shake themselves loose opening a channel for sea water to find it's way into the cylinder.
When the cylinder fills with water and comes up on the compression stroke many things bend and/or break.
If that is what happened to your engine and it will cost $3k+- to rebuild, I would seriously consider just replacing the motor with a 2 cylinder.