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Plomong

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Hello all,

Having changed the oil filter today on my Yanmar 3YM20 motor, I noticed the vent hose shown below in the sump beneath the motor. I cannot for the life of me see where it was previously attached to the motor. There is another vent line attached at the rear of the motor, port side, just above and to the side of the flywheel housing. That is in position, and the nipple is visible, but I cannot find the nipple from which the hose as shown has detached itself.

Could any Yanmar owner or expert here point out exactly where this hose came from on this model motor ??

Thanks for your help,

Plomong
 
Plomong said:
Excuse me for asking, but where is that ???

Have never needed (yet) to drain the cooling water, so don't know where it is.

Presumably somewhere on the lower part of the motor, being a drain, but where-abouts -- front, rear, port or s'bd side ???

Thanks,

Plomong
Click to expand...

If you watch the start of this video you'll see it on the right hand end of the engine.
http://www.youtube.com/watch?v=MDABY33wceQ

It's to prevent the coolant running over the starter motor when you open the drain.
 
Talulah said:
If you watch the start of this video you'll see it on the right hand end of the engine.
http://www.youtube.com/watch?v=MDABY33wceQ

It's to prevent the coolant running over the starter motor when you open the drain.
Click to expand...

Talulah,

No it is not that one -- that one is still on the motor, just above and to port of the flywheel housing.

Plomong
 
noelex said:
I agree with Talulah. It's just a hose to make draining the water out of the engine a bit less messy.

See page 31 here for the locations

http://www.marathondiesel.com/site/images/PDF/Sailboats/3ym20/km2p-1/operation manual.pdf
Click to expand...

Have just looked at page 31 of the manual. I don't ever remember having a hose connected to the rubber pipe, but I could be wrong. Will check tomorrow to see if it will fit on there.

My hunch is that it comes from somewhere at the rear of the motor, on the starboard side, because that is where I found it when mopping up some oil from the tray. I may have dislodged the pipe by my actions, so think it may have been loose, but connected somewhere on the starboard rear of the motor.

Any ideas ???

Plomong
 
Plomong said:
Have just looked at page 31 of the manual. I don't ever remember having a hose connected to the rubber pipe, but I could be wrong. Will check tomorrow to see if it will fit on there.

My hunch is that it comes from somewhere at the rear of the motor, on the starboard side, because that is where I found it when mopping up some oil from the tray. I may have dislodged the pipe by my actions, so think it may have been loose, but connected somewhere on the starboard rear of the motor.

Any ideas ???

Plomong
Click to expand...
No it's not connected to the rubber pipe. There are 2 on your motor, both push on to a small metal pipe. They are only a push fit so they fall off with vibration, but are only needed when draining.
If one is still connected look at the fitting and search for another like it.
 
noelex said:
If one is still connected look at the fitting and search for another like it.
Click to expand...

That's what I did today, but couldn't see any other similar fitting.

As Talulah has suggested, it may be from the right side of the motor, near the oil filter, where I have no visual access -- can only just get my arm in there with difficulty, and very difficult to use a tool to unscrew the filter. Looks likely there may be another nipple there. Will look tomorrow with the aid of a mirror.

Thanks,

Plomong
 
Talulah said:
In that case it's off the seawater drain plug as shown as item 2 on page 32 of the above manual. This is close to the oil filter which you were working on.
Click to expand...

OK, OK. That could be it !!!

I'll look there tomorrow with the aid of a mirror, as I cannot see in there, only work by touch and feel !!!

Thanks,

Plomong


PS. Will report results tomorrow night.
 
Plomong said:
OK, OK. That could be it !!!

I'll look there tomorrow with the aid of a mirror, as I cannot see in there, only work by touch and feel !!!

Thanks,

Plomong


PS. Will report results tomorrow night.
Click to expand...
A good tip is to use a small digital camera. It can get into places your head will never fit. If you cannot fit the hose back on don't worry it's not vital.
 
noelex said:
A good tip is to use a small digital camera. It can get into places your head will never fit. If you cannot fit the hose back on don't worry it's not vital.
Click to expand...

noelex and Talulah,

I've searched today for over an hour with the aid of a mirror and a digital camera and cannot find any sort of nipple or attachment from which the hose may have become detached.

Unless someone can show me the two hoses on their Yanmar, it must, for the time being, remain a mystery.

Will contact another boat owner near here who bought the same model boat at about the same time as us. Maybe having a look at his motor "in the flesh" will give some clues. However, can't contact him until mid-June.

Thanks for your suggestions and ideas,

Plomong
 
noelex said:
Here is what the fitting looks like (without the hose)
This is taken today on my Yanmar 4 JH4AE, it will be the same fitting, but not the same location on your engine.
Hope this helps.

http://i169.photobucket.com/albums/u227/noelex/e56125c8.jpg
Click to expand...

Very good, noelex. With that photo I think I've found the nipple !!! See attached images, the first being the known one, with hose still attached. The copper-coloured nipple put me off as I was looking for another like that one.

The one like your photo can be seen in the second image, middle-left. It's quite unlike the first -- no nipple, just a short length of pipe onto which I'll push the hose.

Thanks.

Plomong
 
Yes that's it. The second photo is exactly the same fitting I have for both hoses for my Yanmar 4JH4AE.
For my engine both the water drains are for antifreeze, on yours I think one is for antifreeze and one is for raw, salt, water. That is probably why the two fittings are not identical on your engine.
 
At the gearbox end of the fresh water heat exchanger there is a drain valve with a clear plastic tube.

There is also a drain underneath the heat exchanger just above the fuel lift pump. I think that should also have a tube.
 
noelex said:
Yes that's it. The second photo is exactly the same fitting I have for both hoses for my Yanmar 4JH4AE.
For my engine both the water drains are for antifreeze, on yours I think one is for antifreeze and one is for raw, salt, water. That is probably why the two fittings are not identical on your engine.
Click to expand...

noelex, Talulah and Tomahawk,

I fitted the drain pipe last Monday so all is as it should be again. Thanks for your help.

Plomong
 
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