Yanmar Woes

[Dockhead]

Originally Posted by SaltyMonkey

Very strange, but I confess I am learning a lot from your experience

Are you talking about the dipstick? Yeah, beats the s*it out of me too. Never seen such a thing in a lifetime of internal combustion engines.

Or the revs? I would have preferred a Perkins. The M90, roughly equivalent to my Yanmar, produces 90 horsepower out of 4200cc (!) of displacement, huge lump of iron weighing almost 1000 pounds. Naturally aspirated and dead simple, redlines at 2500 RPM and cruising speed of 1900 or so.

My Yanmar, by way of contrast, produces 100 horsepower out of only 2000cc. It does that by having the bejeezus blown out of it with turbocharger and intercooler. Redline 3800, cruising revs (in my hands) 2400 to 2500. As a result it is smooth, quiet, powerful, and fuel efficient, not to mention light and compact. But give me the simple Perkins any day. A yacht motor is supposed to run no matter what, and to be capable of being fixed by a monkey with a sledge hammer. IMHO.

[hpeer]

Another 4JH4-TE owner here.

I was puzzling over the oil readings on mine also before reading this thread. I have not run the engine in a couple of weeks but checked the oil yesterday.
1 - pulled dip stick - full
2 - put dip stick back in and pulled - down to fill line
3 - again, in less than a minute - half way down.

But here is the beater for me.

How are you supposed to check the oil BEFORE using the motor if you have to check it 10 minutes AFTER using the motor?

BTW No yellow tag on mine.

[Therapy]

Originally Posted by hpeer

Another 4JH4-TE owner here.

I was puzzling over the oil readings on mine also before reading this thread. I have not run the engine in a couple of weeks but checked the oil yesterday.
1 - pulled dip stick - full
2 - put dip stick back in and pulled - down to fill line
3 - again, in less than a minute - half way down.

But here is the beater for me.

How are you supposed to check the oil BEFORE using the motor if you have to check it 10 minutes AFTER using the motor?

BTW No yellow tag on mine.

I am just flabbergasted that they could be such a large operation while doing stupid **** like that.

I surmise they (the motors) don't really care what the level is as long as there is some in there because it is (surmising again ) obvious to me that even though some of you know how (or thought you did ) to check the level and do, there have to be a lot of owners that don't, just like owners of other engines, and they run for a long time anyway.

Long sentence I know. Sorry.

Maybe I'll get a Yanmar the next time I need a diesel.........

[Charlie]

Dockhead:

I have a 4JH4E non turbo. I had a leak in my lift pump diaphram and was making oil. I sniffed the oil -- no diesel smell. It didn't look like diesel. Then a very smart mechanic in Mexico looked at the oil from the dipstick and rubbed it in his fingers and sniffed it. He couldn't smell any diesel either. Finally after I had changed the oil and run the engine for an hour he stuck his finger in the bottle of new oil and rubbed his fingers together and then did the same with the oil from the dipstick and it was obvious that we were leakign diesel. I didn't have and couldn't get a new lift pump so I installed an electric pump and looped the connection to the lift pump. I didn't make any oil after that. The symptoms were quite a bit different then yours. White smoke and if you brought RPM's to high the engine would race. Don't know if the difference would be attributable to the turbo or not.

[noelex 77]

Originally Posted by hpeer

Another 4JH4-TE owner here.

I was puzzling over the oil readings on mine also before reading this thread. I have not run the engine in a couple of weeks but checked the oil yesterday.
1 - pulled dip stick - full
2 - put dip stick back in and pulled - down to fill line
3 - again, in less than a minute - half way down.

But here is the beater for me.

How are you supposed to check the oil BEFORE using the motor if you have to check it 10 minutes AFTER using the motor?

BTW No yellow tag on mine.

The difference in reading between 1 and 2 is explained by the seal the dipstick makes. Reading 1 is incorrect and can be ignored.
The difference between 2 and 3 unusual. My engine gives very consistent readings if they are taken at the same time.

To answer your last point I always check the oil before starting the engine (by removing the dipstick cleaning it insert remove and take the reading) and I know a reading just a bit above full is perfect. It will then be 3/4 full if I measure it again at 10mins after shutdown.

My engine has never used any oil and I don’t see it as a great problem just a quirk of the engine. The only real problem is if you didn’t know this quirk and measured the oil level at 30 mins after shutdown you could think the engine had used a lot of oil and overfill it.

[goboatingnow]

Dockhead,

If you had a serious overfill, its likely the crank was stiring through the oil, and hence it wips it into a foam and in that state its a very poor lubricant, Hence the noises may just have been lack of lubricant.

Turbos dont generally fail slowly, usually the bearings and seals go and thats trashes the turbo and can throw oil everywhere.

Dave

[hpeer]

Originally Posted by noelex 77

To answer your last point I always check the oil before starting the engine (by removing the dipstick cleaning it insert remove and take the reading) and I know a reading just a bit above full is perfect. It will then be 3/4 full if I measure it again at 10mins after shutdown.

Thanks for a very useful post.

I never thought I would need instructions on how to read a dip stick. Learn something new every day.

[delmarrey]

Just one last picture so all can see for them selfs...............



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[meyermm]

Firstly when a fault appears sometimes there is more than one and this confuses the fixer as he is looking for one cause. Lubricating oil drains back to the sump from the turbo usually via an external pipe. If the oil is overfull combined with excessive heel the oil may have banked up and caused the turbo to stall. Usually this will force oil through the seal so in this case probably unlikely as no oil appeared in inlet. Noticed that injectors were done originally but no mention of pump? Coolant loss is totally separate to blocked fuel filters? Me thinks fuel blockage caused by rough weather is most likely cause of problem. When turbos fail to this extent it is usually obvious once examined and as has been said previously when bearings go seal is unable to seal so oil will appear in intake side of turbo + manifold. As to Yanmar, turbos etc, most diesels these days are fitted with a turbo be they truck, car etc. Truck engines do a million kms between rebuilds often and they operate under a much more harsh environement with loads and rpm going up and down constantly, underbonnet temperatures being much higher etc. Unfortunately most boat owners do not come from a mechanical background and do not see a problem developing until it hits.

[olaf hart]

The newer Yanmars are much cleaner too.

I have eye issues with diesel fumes, changed over recently from 2gm20 to a new 3ym30 and I really notice the improvement in eye irritation motoring in a following wind.

The previous generation to the gm series were even worse, particularly the YSE and SB series.

I certainly wouldn't be looking around for an older design such as a four liter Perkins.

[Dockhead]

Originally Posted by hpeer

Thanks for a very useful post.

I never thought I would need instructions on how to read a dip stick. Learn something new every day.

+100000

You can say that again!

[Dockhead]

Originally Posted by olaf hart

.

I certainly wouldn't be looking around for an older design such as a four liter Perkins .

Well, I would, if I had a choice. Truck engines are not really a valid comparison, for two reason:

1. They are much bigger and therefore all parts of them are more rugged, than say a 2000cc 4 cylinder marine diesel like my Yanmar.

2. If you have an engine failure in a truck, you pull over to the side of the road and call the service center on your mobile phone and pour yourself another cup of coffee while you wait. If you have an engine failure at sea, you can die. Slight difference.


I am not quite comfortable with the idea of these Yanmars. The very high specific output -- 50 horsepower per liter -- is the same as my first BMW, considered a pretty high performance gasoline engine at the time (admittedly years ago). That just doesn't seem right for marine use. By contrast, the three cylinder diesel in my genset (also a Yanmar) puts out only 14 horsepower out of 1000cc. At 1500RPM. I like that. I like that a lot. That's a marine approach to power. Yes, I would prefer the Perkins.



All that being said, thanks everyone for all the really interesting advice.

After changing the fine filter and pumping out the excess oil, the engine runs perfectly. I ran it for five hours and ran it harder than I usually do, and didn't lose any coolant. When the engine is cranked up to 2800 RPM the turbocharger sounds like a jet engine, merrily doing its work (I do have to say that I love the sounds my Yanmar makes). It sounds healthy. Whether it was the oil or the fuel filter, I will now never know, I guess. I've sure learned about dipsticks, however!

[lorenzo b]

I once had a cat named Dip Stick, or was it a sex toy? I forget.

[Charlie]

Dockhead:

One more thing about oil level. In my manual there were two different amounts of oil under the heading of capacity. One was with the engine level and the other was with the engine set at an 8 degree slant. The slant required less oil I believe it was a full liter difference. Next time I am at the boat I will check my manual.

[delmarrey]

Originally Posted by Charlie

Dockhead:

One more thing about oil level. In my manual there were two different amounts of oil under the heading of capacity. One was with the engine level and the other was with the engine set at an 8 degree slant. The slant required less oil I believe it was a full liter difference. Next time I am at the boat I will check my manual.

You are right. It's a different amount for different motors but when the motor is tilted back in a boat for the prop shaft it increases the oil level. The dip stick is in the rear of the oil pan unlike cars where it is usually in the middle. I guess, so it makes it EZ to drain the oil through the dip stick tube.


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