Oil Leak on 6LP

[Tree]

Guys,

Anyone ever seen traces of oil in the bilge from their Yanmar 6LP engines?

It looks like it is coming from the raw water pump area, potentially the bolt that goes through the casting. It's only come about since the weekend where we were in some pretty lousy stern seas and the engine was having to work pretty hard.

From what I have read over on boat diesel, it could be the raw water pump, but it could also be the core plug behind the injector pump?

As always, thoughts and input are appreciated.


Lee

[RobS]

Definitely black engine oil, not fuel oil? Have you checked the oil cooler and oil cooler lines? There are also oil return lines on the opposite side of the engine..

[Tree]

Definitely black engine oil, not fuel oil? Have you checked the oil cooler and oil cooler lines? There are also oil return lines on the opposite side of the engine..

Its definitely engine oil, first thing I checked was the oil cooler and around the filter. I know the boat had a new water pump fitted just before we bought it as the survey showed a leak and I had asked for it to be changed.

It may have just been a case of the engine being pushed hard with a heavily pitching boat but even so, I'm not happy with the amount of oil that has come out (about 1/4 of a pint).

Hopefully it's not raining at lunchtime today and i'll be able to go and lay down on the deck and have a really good look - the only place I can see traces of oil are on the side of the water pump bracket, I've even checked all around the sump knowing that was replaced 100 hours or so ago.

The only real places that i can think of for an oil leak like that would be crank case seals, oil cooler, filter, sump and the seal on the raw water pump.

[Tree]

Pretty sure I've found the problem - as pointed out here on boat diesel

http://boatdiesel.com/Forums/index.cfm? ... d_ID=19317

Thankfully I've caught it in time before we had a major issue

[RobS]

Good work. Keep us posted and maybe a few more pics when you have a chance.

[Tree]

I'll get some better pictures hopefully when I take it all apart, unless I get my mechanic to do it if I don't have the time.

It looks like either the fuel pump or the oil cooler has got to come off to get to it though - one of those PITA jobs!

[RobS]

Given this picture can you be more specific as to where the leaking plug is?

[Tree]

Just about where the red arrow is (excuse the lack of artistic skills) if you look down at the left hand of the oil cooler there is a small gap, you'll need a torch as its about 8" down.

I'll try and get down on the boat tomorrow lunchtime and get a better picture for you in daylight.

[RobS]

Perfect, got it. So when you referred to removing the oil cooler you actually mean fuel cooler, that threw me off.. And by torch you mean flashlight

[Tree]

Bingo! You Americans with your adapted English!

[Serenity]

I tried using my torch to locate the plug, and things started to melt and smell funny. The flashlight, oh!

[Tree]

I tried using my torch to locate the plug, and things started to melt and smell funny. The flashlight, oh!

[Dudley]

My banjo bolt on the bottom of the oil pan rusted through. see

sf260w.com/Trip2011

for details. but I lost over a gallon of oil into the bilge before we found it. When I had the new 6LPA-STP installed the used an after market banjo bolt and it rusted through.

[Tree]

Hopefully, this should give you a better idea of the core plug location - as yet, still no part number from Yanmar.

I think, without getting the books out, the oil pump is just behind this?

[Tree]

Just found a better picture online - its right next to the red label on the left hand side