Ding like bell sound like pinking from diesel Yanmar 2M15 2006 version after low oi

[bouncycastle]

Originally Posted by Svanika

https://www.yanmarmarine.com/theme/y...-datasheet.pdf

I can not get the link to work ?? keeps to do 404

[bouncycastle]

Originally Posted by lituya1617

This is a strange story. The Yanmar 2YM15, 13.5 HP, diesel engine pan bolts are far above the level of the oil in the base. If a bolt falls out completely and nothing else happens, the gasket will probably prevent any oil leak anyway. These are cast pans with considerable rigidity. The loss of one bolt will not change the pressure on the gasket by much. .

agreed I suspect that oil drips from above and arrives the bolt to make it look like it leaks at the bolt from the oil pan

Originally Posted by lituya

So, how did this engine leak so much oil so fast? It seems you have the wrong source for the leak, if it is as you describe. .

yeah I never expected this confused how this happens so fast

Originally Posted by lituya

On the other hand, the really strange way Yanmar put in the dip stick on this engine - there is a tight curve in the dip stick tube and the tube enters the base far below the level of the oil on the side of the pan - makes it possible for the dip stick tube and fitting to the side of the pan to be the source of a pretty fast leak. .

The dip stick is not in the zone that seems to leak but the leak might flow from the oil dip stick and travel to back of engine ??who knows at this stage under the engine is a big oily mess

Originally Posted by lituya

In the future, never run an expensive and necessary engine without an oil pressure guage in addition to a low-pressure warning light/alarm. The alarm is set far too low for running under load and so will not warn of low pressure (for load) even though damage may occur with continued running. Idiot lights are for idiots. .

yes will have to see how to attach a suitable solution pressure info instrument to this installed simplex oil low pressure switch alarm system . All ears as to how this can be done

[Compass790]

I guess you don't have a sump drain plug or can't get to it on the 2ym15 then?
I understand now why you were desperate to flush.
You can get a tee to enable running both an oil pressure gauge & an oil pressure sensor such as this: https://www.aliexpress.com/item/4000...archweb201603_
I'd try a place that deals with air compressors or airlines or a pipe fittings supply.
Take all the pieces you want to cobble together with you & they should be able to sort you out. But you have more pressing issues ATM

Your plan to run an outboard as well if caught in the rough weather is a nono IME. The outboard doesnt spend much time in the water & you dont want to be dealing with 2 seperate engines. However only you can make a judgement as to the relative value to you of fuel consumption v safety of reserve power. FYI our yanmar ysm8 uses about 700cc per hour at 4.5knts but we are overpropped so fuel economy will be better I suspect because of that.

I disagree partly with post #59 as it's not guaranteed you have destroyed the engine, that remains to be seen. It's possible but I'd do what you plan first before stripping it. You are not having any luck Dermot with no starting now.
If you need a starter there are much cheaper ones on Ebay, no idea of the quality.

Yes it's a pity it only leaks oil when running but it should be easy enough to find when you get it running at the rate it leaks.
I wish you better luck.

[Sailor_Jeff]

I suggest, since you do not seem very experienced in small Diesel engine repair you hire a very experienced and able body mechanic to thourouly check your engines. This should involve a hook up to guages and really check it out. Then rely on their judgement.

I don't believe your low oil caused a problem nor the type of fuel based on just your words, not until I would do a vibration analysis and compression test. That will tell us a lot. I would check it for you but I'm on the other side of the world.

The experienced and highly recommended mechanic may seem expensive, but they will save you a lot of money in the long run. Then you may change it your self or do what ever maintenance you can and hire the other work.

Originally Posted by bouncycastle

Another mechanics forum suggested that there is sticky valve stem with piston hitting the stem or some piston valve stem interaction

Open to ideas a sticky stem can be replaced big job to take head off but still possible less bad than big end bearing issues

Typo the engine is yanmar 2ym15 of ~ 2006 era 2 pot ~ 600cc 12.5 HP approx

[Compass790]

You may be able to get the starter repaired. It will be definitely cheaper than buying one from Yanmar.
You can try spinning the motor up with the engine stop on or decompression levers engaged ( if it has them) to look for oil leak. Make sure you turn water off & do not crank so long that you burn out starter. Maybe get some flourescent dye to put in the oil to help trace leak. Have a good light & flexi mirror. I realise it's hard to see in your engine no- room but it must be pumping oil quite fast. Sadly it's not so easy to see leaks when the engine is cold as oil is thicker but yours is likely to be from a pressurised line or galleryso should be visible.
good luck

[bouncycastle]

Update

I got starter to work with the tap it with hammer trick has worked perfectly since then so might be a one off event hopefully

I used absorbent Kitchen paper around all suspected sections of engine where the leak might be

I ran the engine both at cruising throttle 50% gas both engaged to prop while tied to marina and tick over for about three hours
Apart from small oil leak about 1/4 cup everything seemed to work well.

The absorbent paper jammed around the oil pressure switch had got oil on it

This suggests that it is ~99% the oil leak is there and ~1% possible the oil comes from higher up the engine and drops onto the oil pressure switch or comes from the oil filter beside the oil pressure switch .

The replacement OEM oil pressure switch won't arrive before 20 the July with Yanmar spare parts supply lines interrupted with the water infernal virus

Tommorow I will probably have to remove the oil pump fuel filter and water pump and oil and oil filter to give extra room to try to remove the oil pressure switch .

If the offending oil pressure switch passes the tests to show it is the correct Type British threads and is the threads are good then I will try to install it so there is no leaks

Then after that I will get a local mechanic to run tests with oil pressure equipment and verify engine optimisation s good and start the sail the Irish coast for the summer

@ compass 790
700 cc of fuel per hour is very interesting .
What size boat in tons and type and size of prop and gear box reduction and approx RPM is that

my boat is 3.5 tons but narrow 1968 type hull don't know the RPM it is faulty and haven't calibrated the speedo and don't know reduction and 12*9 prop


yes i know the outboard prop will exit the water but I will make a well in the back hatch behind the spade rudder so it should perform enough to go the few miles to exit some nasty bay I got trapped in ..

keep you posted

[lituya1617]

The saga of water in the oil, an engine that will not start, and several books worth of speculation about what is wrong have left me exhausted. Bouncycastle should hand his engine problem over to someone who understands basic engine mechanics. All the framming around he is doing is a waste of energy. If you cannot follow the standard protocol of troubleshooting an engine, you should never pick up a wrench. You will do more damage than good and you will spend tons of money and time doing it.

[Compass790]

Ok the 700 cc per hour figure is from a 7hp continuous rated Yanmar ysm8. The box is 2:1 reduction & the prop is 12" but I'm not sure what the pitch is. I think it was 10" but I know its way overpropped as we can only get it to 2400 rpm in ideal conditions Its max revs is 3150 in neutral & it's supposed to be propped to get that driving. The 700 cc per hr figure is at about 2200 rpm but it might be slightly more say 800 I'm not positive but we used 58 litres in 101 hrs with hardly any battery charging at 1500rpm ( maybe 6-9 hrs) on last trip.
Not sure on the displacement but I'd guess 2 tonnes & closer to 3 loaded with all our stuff. Its a fin keel & 4'6" draft, 26ft lg, 10'6" beam.
The ysm8 is an industrial engine that I suspect is more heavily built than the 2ym15
so I'm a little relaxed about overpropping ( overloading it) Not sure the 2ym15 would handle overpropping as well.
You can increase the pitch on your prop if you cannot increase the diameter to get more speed at lower revs. I would rather overprop it than replace with a 1GM10. As other poster says you can just throttle back.
Overpropping is the easiest way to reduce fuel consumption but you have to be careful not to overstress the engine. Its like an overdrive in a car.
My guess is you would need no more than 5hp to do 4 knts in a flat calm

[bouncycastle]

@ compass790
Thanks useful info to know .
my maths would agree about 5 hp for 2.5' tons for 4 knots when I compare the numbers against similar craft using electric drive and outboards in calm sea condition

My engine with 2 pots similar 3 blade prop 12*9; at what i recon is ~2200 RPM ( Taco broken ) seems to do about ~3.5 knots but my weight is closer to ~4 tons loaded up..
However Yanmar graphs indicate that 2200 RPM ( taco is broken )will use closer to 2 liters per hour and full power three liters per hour
The math for my boat indicate 30 feet 3.5 ton requires about ~6 HP tondo ~4 knots in calm seas

There is extra friction from two pots versus one pot so the previous owner said 1 litre per hour.
I suspect that is the figures from the past when boat had a 9 HP engine and smaller alternator like 35 amps.

i suspect a previous owner who swopped out the original 9 HP opted to not increase the prop size to keep the fuel use down or because there is risks the props shaft bearing cannot work with bigger props.

Yes over propping and deep pitches or two blade larger props with keel interference can create all sorts of problems including killing the engine

Under propping also has its problems.

I am starting a new thread on the subject of how to remove the drag of alternator to give all the power to the engine using some suitable switch rather than remove the belt drive .

In time I hope to get most all battery power from solar power 200 watts plus so am interested to take alternator out of line except as back up if the sun is not shining.

[bouncycastle]

Update Friday

Any body know where I can get the right tool to take off the oil pressure switch

My socket 22 mm seems to be too small

Also on you tubes on removing a oil pressure switch many use imperial sized deep type socket thin walled like a larger version of a spark plug tool.

I suspect with my Yanmar normal imperial socket cant fit as switch is deeply recessed in hollow region so needs to be a thin walled spark plug deep socket tool

I don't know the size of this tool and the replacement oil pressure switch is not due to arrive before 20 July earliest to use that to measure the size.

Although in this time I think I do not need to remove the oil pressure switch I want to have the tool in case I need to replace it soon or make a suitable oil pressure gauge solution in that section of the engine block or maybe that is the leak that needs to be fixxed


I think I solved the oil leak problem but now have a rubber hose leak on the heat exchange
Dang

Best I can tell it is not the oil pressure switch where the oil leak is and one hour engine run after fixing leak suggests this is the case

Close to the oil filter is two objects attracted to the engine block

The higher up device is the oil pressure switch with its positive electric blower lead

Slightly below the oil pressure switch is a large 15 mm wide hexegon about 20 mm brass devise with a short T pipe junction on the side and there is another brass 12 mm nut with male insert that seems to be there to block of the T junction pipe on the side ...

No threads on this T junction short 10 mm pipe with diameter about 6 mm

I suspect this device is there if you wish attach a oil pressure meter
First you remove the 12 mm internal bolt with male insert and screw in a suitable oil pressure meter with hollow bolt male insert .

Possibly it is merely a oil removal devise so I am not sure .



My instinc was that is the device that has the leak .and it leaks at the engine block beside the hexegon part

Possibly there is a rubber gasket missing.???
My finger nail could get under the hexegon bolt .

No sign of any PTFE tape on the devise when I took it out

My logic is brass expansion on the engine block is different to iron engine block and when engine gets hot after few hours the oil leak starts


So I removed it and put it back with PTFE tape
Then I ran the engine for a hour no sign of oil leak but then a rubber hose pipe burst a hole in itself

The hose is part of the heat exchanger comes out the top of the best exchanger and flows down in front of engine ..

The hole is like screw driver went into the rubber hose and looks like it was repaired in the past

With what seems to be a mega problem with supply of parts this hose replacement isn't going to happen soon son looks like I need tonfix old rubber hose

There doesn't seem to be high pressures on the hose so hope to fix it Saturday test engine and exit marina on Monday

Fingers crossed

[skipperpete]

The brass hex 15mmx20mm that you describe sounds very much like the engine coolant cylinder block drain fitting, it usually has a short length of clear plastic hose on it too. These are often blocked hence nothing coming out when the centre plug is removed.
Pete.

[Compass790]

You don't need to buy genuine Yanmar hose. Just try a radiator shop or car parts place for radiator hose, it will be 1/10th the price & just as good.
If your boat has a 1" shaft you can increase the prop pitch or diameter if it has room to increase diameter. I wouldnt worry about the stern bearing. FYI the berth neigbour with a sistership to ours has a 20hp kubota driving througt the same shaft as he had with an YSM8 with no problems. He of course has a prop to suit the bigger engine.
What you want to do for max economy is drop the revs that the motor does for a given speed. The best way to do this is with a variable pitch prop & an exhaust gas temperature monitor which are obviously not going to be in your budget so the best alternative for you is to size a prop that will drop the maximum revs you can get under power to say 2800.
Note that our Yanmar does a fair bit less than the official Yanmar fuel burn figures assuming our hourmeter is right. ( not horribly out I'm sure but havent checked it exactly).
Haven't researched the relative efficiency of single vs twin but man a single vibrates a lot & is noisy. Guess it stands to reason a twin would have more friction losses.
I would happily swap with engines you if I was in Ireland ( after I had done a compression & oil pressure check)

The previous owner had it completely wrong if he did not get a new or used prop with more pitch or diameter when he fitted the more powerful engine.
If you don't believe me go to the vicprop calculator & put in the different figures for the 2 different engines you are thinking about.