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TampaBaySailor · 09-02-2015, 12:00

Quote:

Originally Posted by sailorchic34

As SVFraidKnot said, put a wrench on the crank pully bolt and see if it turns over. Pull the decompression levers first, just so there is no chance it would start.

If it turns easily, your lucky and you just need a $58 oil line. If it does not turn, Well lets not talk about that. Though if the oil leaked out and the oil pressure alarm did not go off, then odds are it might be a tad stuck.

Depending how handy you are with a wrench would effect the cost of a rebuild. Figure $700 ish for machining and about $1000 for parts. (Bearings are cheap), if you can turn a wrench. If you have to pay someone else to do it, it would cost as much as a new engine.

Beta BTW is the engine to get as they can match up the engine mounts, which makes a repower soooo much easier.

Sailorchic - This is great help. However one question - what are the decompression levels and how do I "pull them"? Sorry to be the diesel "newbie"...

roland stockham · 09-02-2015, 12:15

When did you last check the oil? Do you have problems with the engine smocking particularly when cold or running hard (ie strong headwind) Another clue is that the transom gets very dirty around the exhaust. If any of these are present you are looking at a complete rebuild.
If the oil did not leak into the bilge it must have gone through the engine. Either this happened slowly because of ware = full rebuild replacement. Or quickly due to internal brakage (pistons, rings or head gasket are most likely) If it resulted in a shut down you may be lucky and just need to repair what broke. If the engine ran for more than about 15min without oil it is probably a right off or at least 'walking wounded' I might trust it in a car but not on a boat.

**sailorchic34** · 09-02-2015, 12:18

Quote:

Originally Posted by TampaBaySailor

Sailorchic - This is great help. However one question - what are the decompression levels and how do I "pull them"? Sorry to be the diesel "newbie"...

On the side of the valve cover will be three levers. pushing them toward the front of the engine keeps the exhaust valve from seating which decompresses the cylinder. Very handy in a runaway condition. So before turning a wrench on the crank pully nut, push the levers toward the front. Also handy when bleeding the engine.

After you check that the crank turns or not, just flit them back towards the back of the engine. The decompression levers were there for hand crank starting. You would use a hand crank that fit on the end of the timing gear, open the levers, get the engine spinning and flip one lever close to get it going. Ah the good O' days.

Hard Rock Candy · 09-02-2015, 13:19

Why is it called a GM motor?
mine was a two cylinder Yanmar and that is all I ever heard it called. Just curious. Mac

mitiempo · 09-02-2015, 14:33

YSE, YSM, and GM among others are all prefixes for Yanmar models

TampaBaySailor · 11-02-2015, 07:57

Thanks everyone for all the help. I checked the engine rotation and the good news is that it is not ceased up. Seems to turn easily and smoothly with the breaker bar.

It looks like the oil line is the culprit. I will replace and hope for the best!

Greatketch33 · 11-02-2015, 09:29

Quote:

Originally Posted by TampaBaySailor

Thanks everyone for all the help. I checked the engine rotation and the good news is that it is not ceased up. Seems to turn easily and smoothly with the breaker bar. It looks like the oil line is the culprit. I will replace and hope for the best!

Great to hear!

The problem with the external oil lines is that it only takes a tiny pin hole to be had and the oil goes quickly.

It's difficult to inspect the line too.

Best,
Great ketch 33

Sailorman Ed · 11-02-2015, 18:24

Found these pics - is this the oil line in question?

**sailorchic34** · 11-02-2015, 19:17

Quote:

Originally Posted by Sailorman Ed

Found these pics - is this the oil line in question?

The small 1/8" grey line behind the fuel line is the external oil feed. You can see it also below the starter on the 2gm.

Greatketch33 · 15-02-2015, 09:40

Quote:

Originally Posted by Sailorman Ed

Found these pics - is this the oil line in question?

That is the exact oil line I replaced on my Yanmar GM20 this past summer. It wasn't leaking but as part of my replacement of hoses on the engine I inspected the oil line by removing my starter -- easier to get line out for me --- and discovered that the metal line was showing wear.. As if it was rubbing against the starter. Well replace now before it wears a hole while I'm in the middle of navigating through a busy channel.

Good job!

**JPA Cate** · 15-02-2015, 20:54

Quote:

Originally Posted by TampaBaySailor

Hi,

I have a 20 year old Yanmar diesel 3GM30F with unknown number of hours. A few days ago while underway at ~2000 rpm, the engine died without warning after running for 3 hours. A quick inspection showed all engine oil had leaked out.

After a tow back home, I inspected the engine and could not find any obvious place the oil leaked out however the dipstick clearly showed no remaining oil.

Does the CF community have any suggestions what I should do next? Obviously I need to figure out what happened (why the oil leaked) and additionally how badly damaged my engine is from running without oil.

Thanks!

FYI, one can purchase oil pressure alarms, that go off when the pressure gets low. Might be a useful addition after you repair things.

Ann

MBWhite · 15-02-2015, 21:28

Quote:

Originally Posted by Greatketch33

That is the exact oil line I replaced on my Yanmar GM20 this past summer. It wasn't leaking but as part of my replacement of hoses on the engine I inspected the oil line by removing my starter -- easier to get line out for me --- and discovered that the metal line was showing wear.. As if it was rubbing against the starter. Well replace now before it wears a hole while I'm in the middle of navigating through a busy channel.

Good job!

Good on you for finding a problem before it becomes one!

If you have lines that appear to be chafing, there's nothing wrong with covering them with a piece of slit fuel line to provide some wear protection. Best way to secure the slit tubing is with plastic zip ties. Wrapping with electrical tape looks better but it only takes a little oil or fuel to dissolve the adhesive on the tape. Zip ties work forever and are also easy to remove should the need arise.

Greatketch33 · 16-02-2015, 04:38

Quote:

Originally Posted by MBWhite

Good on you for finding a problem before it becomes one! If you have lines that appear to be chafing, there's nothing wrong with covering them with a piece of slit fuel line to provide some wear protection. Best way to secure the slit tubing is with plastic zip ties. Wrapping with electrical tape looks better but it only takes a little oil or fuel to dissolve the adhesive on the tape. Zip ties work forever and are also easy to remove should the need arise.

Thanks MBWhite, yes you have provided I good idea. Wish the snow was gone and the temps were 70 degrees higher than zero so I could get back to messing about in the boat.

gonesail · 16-02-2015, 05:31

Quote:

Originally Posted by Ann T. Cate

FYI, one can purchase oil pressure alarms, that go off when the pressure gets low. Might be a useful addition after you repair things

actually the yanmar 3gm control panel should already have an oil pressure alarm. you should have heard it when you turned the key before it started. if not it needs to be fixed and could be as simple as a corroded electrical connection. the seloc yanmar book is a great source of information.