Yanmar Smoking and Making Oil

[Gene :^)]

Call the injector shop that did your injectors and find out what pressure they are set to.

Delongdubois stated that there are 165bar and 200bar injectors for this engine. If you have a 200 bar engine and they set for 165 bar you would be dumping way too much fuel and running rich.

Get numbers off your injection pump and find out what it should be, 165 or 200.

Lots of phone calls could solve this one.

[Tspringer]

We tested boost and its low... we cannot run past 2950 rpm and 8.5lb boost. If the issue were the injectors running rich would we still be unable to get the rpm and boost numbers? I could see running way rich and making smoke but the engine would make the revs and boost.

I think its either a bad turbo or bad injection pump and I am trying to find a rebuilt turbo now, so far no luck.


Terry

[Gene :^)]

Just called an injection shop.

Oregon Fuel Injection, diesel fuel injection pump, turbo, injector and diesel performance product specialist.

He is very confident it is the turbo and absolutely feels that washing the turbo washed debri into the bearing and is causing it to drag.

[um saudade]

Terry, I’ll still say it is the turbo. You have had several posts here by people who know far more than I have and they have given you some good ideas as to what to check out. This I know to be true: Black smoke is good compression so you do not a serious internal engine issue, rather it is in the periphery.

Do you have a shop manual ? (Here is my plug on sailing: Have the tools, have the parts, have the books and know how to use them all.)

Anyway, find out what the exhaust pressure should be and find a place to tap into the exhaust and measure it. On most engines just a few lbs. of backpressure wreaks havoc with the flow. That seems to me to be the only other thing that could cause this problem if you are sure the intake is clear. How complicated is the exhaust flow? A lot of boats have an over the river and through the woods exhaust, potentially having lots of places to cause a restriction.

I have seen rags in the intake and have seen an exhaust filled up with dog food by a pack rat who thought he found the perfect place to store a winter supply of treats (No, not on a boat!)

When you have looked in the likely places and found nothing you must look in the unlikely places. Having said that though, I would get the Turbo to an expert and definitively rule that out.


I have a good friend who besides being a good mechanic is one of the brightest people I know. Years ago he came up with a phrase that I have subsequently come to call John’s Axiom: "Nothing is too complicated once you get it figured out."

Um Saudade

[Northeaster]

Tspringer - Sorry if I missed this ( I did read all of the posts quickly).

I didn't see where you answered the question of whether it would achieve full rpms while in neutral. Can it?

Although I don't believe it is the prop either, based on the fact it is clean, opens correctly, etc.. But, I will tell you that a small change in pitch can make a big difference, and lots of smoke. I bought my 30' boat, with a old 15hp Yanmar, and it put out lots of black smoke at 2200 rpm or so, It would not rev any higher (or I didn't push it as it didn't sound / fell good).

I had 1" of diameter and 1" of pitch removed (from a 15x10 to a 14x9) and I now can rev 3200, sounding great, with no black smoke.
Before repitching I was told (even by the prop expert wgo did an excellent job on the prop) that I would only get about 200-300 more rpms, after the change. My theory, as to why such a huge gain, is that my engine only has about 8hp at 2200. By depitching, It allowed the engine to rev faster - which in turn produced more HP and allowed it to have more power, rev faster, etc. I now have about 13hp available is instead of 8.

As mentioned, it is likely somethinhg else, like the turbo. Not sure how hard it is to adjust your prop, but, if you can have a diver take a couple of inches of pitch off for a hundred bucks or so, it may be worth it. If you can't spin much faster, and rev higher, then it was not the problem.

How much weight did you add in cruising supplies? A few hundred pounds may not make a difference, but a couple of thousand might!!!! It may need to be depitched because of this. Diesels like to be worked hard, but they do not like to be overloaded!! (similar to driving a car up a steep hill in 5th gear, instead of downshifting to keep the rpms up, and the engine happy)

[Chief Engineer]

Terry, you said you thought there might me 1/16 inch of play in the turbo shaft
Permissible Radial Play is ,0031-.0051
Permissible Axial Play is .0011-.0023

1/16 of an inch is .0625

1/64 of an inch is .0156

Looks like turbo......

Now as far as fuel in the oil....keep in mind you are trying to put a lot of fuel in
some may be getting ejected as soot.....some may be going past the rings......

[delmarrey]

Originally Posted by Gene :^)

Delmarry, on the road diesels (cars and trucks) have soot collectors in the exhaust. Like a catalytic converter on a gas engine. This cleans up the exhaust by finishing burning any unburnt fuel so you don't see any smoke.

If you look at old diesel big rigs with open exhaust, you will always see black smoke when they shift or pull a heavy load.

Look at a racing diesel truck, they smoke all the time because they turn the fuel delivery to the max for more power.

Thanks for that. I guess that's a good thing. Now if they would only put them on that Mercedes that I always get behind.

[DennisDW]

Hi TSpringer,
You've gotten lots of great technical advice and It sounds like a concensus view of the turbo unit. I must admit that I cringed a bit when I read of your clean up procedure for the blower. I kinda' agree that it could be running slow.

But it's running. That's great news.


We all feel your pain and frustration to be on the cusp of departure, worse, having departed and forced to return. We're human. We go forward, not back. It's got to be demoralizing. -Leaving scott free, now incarcerated by the diesel police.

We'll, let me suggest a plan B: Just leave. Go.

I think you've already fixed the major stuff. Fuel in the oil, that's bad. Poor starting and running is bad. Smoking under max load- not so bad.

I worship my diesels too. I'd never subject them to unreasonable operating demands unless it's an emergency. Too me, an abandoned dream is a near emergency. After all the due diligence you've done and the fact that the motor starts and idles good, and the most important fact: you have two alternate propulsion systems; sail and dinghy motor; I'd just leave.

I would run down the ICW at idle speed, or what ever load the engine can take without smoking. Your problem will be come more or less apparent. I personally think that it will get better as the engine gets a few hours run time on it. Today's detergent oils will clean out the turbo bearings and free up the fan.

What's the risk? A new engine at worst and you've already crossed that bridge mentally. The reality of the worst case is probably less than that. What if the engine does locks up mid trip? You ease out of the ditch, anchor and rig the dinghy on your hip. Or sail. I bet you, like most of us, have had to sail home without power.

The weather's gonna be settled for a day or two or three. Leave, it will do your heart good to be doing something other than fretting. And it will make clear what's wrong on the beast. Some answers are to be found on the road, not in front of the hearth.

In any case, good luck and godspeed.
Dennis

[Laidback]

Hello Terry,
My Experience with 3 different models of Yanmars and your very clear explanation makes a case for the turbo being the problem.
Your opening post has "I had the turbo off during this and I cleaned it out with carb cleaner and rinsed it with hot water plus compressed air. The turbine blades spun freely." What is "carb" cleaner ?
Yanmar service manuals require a Turbo wash every 100 hours - the wash I understand to be a specialized detergent - it used to cost a bomb for 100cc from YANMAR.
I presume you have checked to ensure that the cooling system to the turbo is functioning and keeping the turbo cool ?

When the transmission in neutral - at what RPM does the turbo kick in ?

[Cheechako]

A couple of posters have mentioned weight added to the boat....I'm trying to ferret out how weight is a factor.. or is it?
"A few hundred pounds may not make a difference, but a couple of thousand might!!!! " etc. Is weight a factor or just waterline? If weight were a factor, when I run my engine while the boat is tied to the dock to warm it up good.... wouldnt that be the ultimate "weight"? shouldnt it be smoking like heck if weight were a factor...?
Sorry for the side trip......

[Tspringer]

Thanks to everyone for all the help!

At this point were are in a slip and will be ordering a new turbo on Monday. Hopefully that will fix it.

I have given the prop pitch and boat weight thing a lot of thought. We have clearly added weight to the boat. We added an aluminum arch with solar panels, increased battery bank, watermaker and other gear plus all our cruising stuff. But then again the boat always carried lots of gear. Still, it is possible that we have added as much as 2000lb to the boat. I doubt very seriously its that much, but as a worst case scenario that would be my worse case guess.

Would adding 2K lb to the boat cause black smoke at cruise rpm as well as max and cut maximum rpm by over 500? We are talking about an increase from roughly 35K to 37K pounds or so. Yes, 2K is a lot of weight but I have a very hard time thinking this is the root of my problem. After all, the boat carries 225 gallons of water and 100 gallons of diesel so the weight difference between full and empty tanks could be enough to throw the prop into being overpitched? I doubt it.


A new turbo is the next money dart. If that does not cure it, having the injection pump rebuilt will be next. IF that fails, I will haul and repitch the prop. If that fails.... we will consider an exorcism.

Dennis: the ditch does not work for us, mast is 65ft plus lights and antenna so we need about 69-70 clearance, there are lots of fixed bridges at 65ft.

Terry

[Chief Engineer]

TSpringer.....have you checked out having the turbo rebuilt?

[never monday]

awaiting the outcome of this discussion. I vote it needs a motor

[Tspringer]

I will check on a turbo rebuild monday, pretty much cannot check on anything until then as everyone is closed. Time is a critical factor. If a rebuild entails a 5 day longer process than just buying a new one then thats 5 days in a slip ($$$) and 5 days more of family cooped up unable to do anything. The extra time to pursue the rebuild option may end up costing the same or only marginally less.


Terry

[Laidback]

One small addition to your decision regarding installing a new or rebuilt turbo is to appreciate that the turbo is not a stand alone piece of equipment. On a diesel engine it requires the injectors to be in sync in terms of size and timing, it requires the turbo to be cooled efficiently, it requires the exhaust system to have clear airways, it requires the cylinders, pistons and rings to be in a condition that do not allow vapourized fuel to pass the rings into the sump - the compression ratio to be within design spec.
So once the new turbo is installed, don't be discouraged if the engine requires a little more TLC to get it running as best as it can.