MAN diesel experience?

How much is a set of injectors ? Two years may = many sets :-o

That is true, these are non common rail engines, 2004 vintage. Injectors are a every 2 yr or 1000hrs, whichever comes first. Apparently this is a pretty serious maintenance item that shouldn't be skipped even if the boat is running great and not smoking, etc.
 
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Someone said it in this thread, but the engines will talk to you.

I deal with a lot of German manufacturing equipment. Some of the equipment includes diesel engines, compressors, etc. I've spoken direct to the engineers who designed the equipment and developed the maintenance schedules around them. Many times the service schedules are based on worst case conditions or service intervals that many owners never experience. They usually will break down their service schedule into A, B, and C type maintenance items. A - must do, B - recommended C - inspect/replace as needed... Or something similar. The same German maintenance schedules are dictated with BMW and other car manufacturers. Diesel engines haven't changed much. Clean air, clean fuel, and timing. The same principles apply with MANS. Bring the engines back to baseline at the beginning and then I would assume your intervals on some of the larger expense services can be greatly extended.
 
I will say this from my experience with the diesels, they will speak to you when they are unhappy. But that is only true for express boats. Most bridge boats you can't really hear what's going on unless you go and look for it. So RPM is the only real tell tale of what's going on along with gauge readouts. When the temps and oil pres. are fine I tend to check WOT almost every run, long run's especially. Then when things cool down, I check all the hoses and fuel lines, clamps etc. while sitting in the slip. This has proven to be one of the best tells on how things are going to go. I can't tell you how many disaster I have averted by replacing clamps early because of this. Also with regards to clamps. Try and have all of them replaced with t-bolt clamps, it's worth the effort.

Very glad I turn my own wrenches, because when l break down, it's all my fault, so I tend to not get as mad as I would if I paid someone else to screw it up.
 
I will say this from my experience with the diesels, they will speak to you when they are unhappy. But that is only true for express boats. Most bridge boats you can't really hear what's going on unless you go and look for it.

I've been impressed with the gauge data available on our MAN CRMs. LOTS of info I didn't have before with mechanical diesels, more sensors accompanied by more built-in alarms, etc.

Yes, maybe can't hear as much as I might if I were down below, but I haven't felt limited by that... even on the previous boat with 450Cs.

-Chris
 
My only concern is the damn injector thing every 2 years. All the other requirements are very similar to other diesel engines.
 
I've been impressed with the gauge data available on our MAN CRMs. LOTS of info I didn't have before with mechanical diesels, more sensors accompanied by more built-in alarms, etc.

Yes, maybe can't hear as much as I might if I were down below, but I haven't felt limited by that... even on the previous boat with 450Cs.

-Chris

Exactly, as mentioned, the gauge readouts are great and one reason I converted mine over to having the extra sensors. And with bridge boats that's all you have, not say it's better or worse. My preference is to listen to the engines and one reason I don't travel with the radio on unless I have a few people on board. If it's just myself and my wife, no radio until we anchor or dock. Personal preference and we all do what works best for us. I would never not get a bridge boat because of that, that's for sure.
 
My only concern is the damn injector thing every 2 years. All the other requirements are very similar to other diesel engines.

I know I will get blasted for this, but that is a reason I will never own a MAN powered boat. While MAN's are amazing engines I just don't have the pockets to fund them on a regular basis, not to mention having to pay a mechanic to do the work. Even if I could throw $20K+ every year or two (and that's just injectors), I am not sure I would do that. I am just not made that way, personal defect I guess. :)
 
Here is something I have learned thru a lot of years of running boats and diesel equipment: You can avoid a lot of problems if you learn to use your nose. Diesels have characteristic odors and if you learn to recognize them you can usually head off problems long before they get expensive.

For example, raw diesel fuel has a characteristic odor far different than the typical diesel smell. Burned diesel smells a lot less acrid than raw fuel. Coolant smells different when it is hot and spilled or leaked from hose onto a hot engine surface. The first thing I always do when I get on a boat I am not familiar with, even if it is to just move it to a different slip, is to open the hatch and get in the bilge between the engines and just sniff around. If I smell raw fuel, I won't even start the engines until I find the source of the fuel smell. If I smell that sweet, acrid odor of glycohol, I stop and look for the source ……...I would rather find the leak while I'm tied to a pole in a marina than to look for it while bouncing around in a choppy sea 20 miles off shore.

And, give me an old fashioned mechanical diesel engine over an electronic common rail engine any day. I can fix most anything on them with a pair of pliers and a screw driver, but on an electronic common rail engine, you can't even diagnose a problem without a laptop, and an internet connection to connect you to a diagnostic system at the emgine manufacturer's crystal palace. But I guess that gives away my age………….
 
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I guess my biggest question in all of this is why does MAN require injector testing every 2yrs or 1000hrs, whichever comes first? Do other diesels in this HP range require this testing? I don't see it mentioned for the Yanmar, QSM or CAT variations. Only from MAN, and they are not messing around with the examples. "Imagine starting a weed wacker after sitting for 3 years, carb is gummed up...same as the injectors for the MAN (Tom DeMann quote). Also scares the crap out of you with the usual "if an injector goes bad you'll burn a hole in the piston and then you are looking at $$$$$".

The other one I love from Tom who is a straight shooter no BS guy "go broke trying to save money."
 
While MAN's are amazing engines I just don't have the pockets to fund them on a regular basis, not to mention having to pay a mechanic to do the work. Even if I could throw $20K+ every year or two (and that's just injectors), I am not sure I would do that.

I'm not projecting anything like that for ours -- which apparently don't have that "replace injectors every 2 years" thing going on. Our maintenance schedule doesn't look much different from any other similarly-sized engines, and much of the periodic work looks pretty much like DIY can work fine.


I guess my biggest question in all of this is why does MAN require injector testing every 2yrs or 1000hrs, whichever comes first?

Haven't been following closely; which MANs, again? Gotta agree: that'd put me right off. Is the same boat sometimes available (maybe different years?) with other machinery options?

Maybe it's just a typical German thing, but OTOH I guess its not an across-the-board MAN requirement on all of their engines...

-Chris
 
It's for all MAN engines according to the literature and service bulletins.

I'll try attach the file I have.

The engines I was considering are non common rail. Maybe that makes a difference as well?
 

Attachments

  • MAN service.pdf
    1.4 MB · Views: 88
It'll take me few minutes of incremental editing to get this complete...

But I (quickly) reviewed the thread and my thought (part 1) start with your post #37:


Found these service intervals online. No getting around them as this is straight from MAN.

Technical services

Periodicity of MAN propulsion engines maintenance

Code Service works Periodicity of maintenance
...
A4 Checking of injectors and compression every 1200 hours

And then this, next:

It's for all MAN engines according to the literature and service bulletins.

I'll try attach the file I have.

The engines I was considering are non common rail. Maybe that makes a difference as well?

Our maintenance schedule differs from the #37 one, and also the one you just attached. Your recent attachment says A1 includes checking/replacing injectors (that was A4 in your #37 post, but essentially similar).

OTOH, in our "Service Record Book" (from the MAN website) A1 says:
Changing Both valve caps on expansion tank
Cleaning Intercooler / charge-air pipes / turbocharger
Heat exchanger (pipe cluster​

There's no A4, and there's no mention of injectors in M1-M6/A1/A2.

So I deduce: the maintenance plan you have is NOT for all MAN engines, and yes, I think as others have said, the non-Common Rail apparently does make a difference.

Finally... looks to me like a 2876 LE 405 is the older non-CRM version of the more current R6-800. Both 12.82L displacement. Sound right?

Did the boat you're looking at maybe come with the R6 version in later years?

-Chris
 
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Ha! And I just noticed the one you attached also says "Caution: Checking the injectors of Common Rail engines is not specified." Yet another hint that CRMs wouldn't need that "every two years" thing.

So maybe back to... did that boat sometimes come with R6s in later years?

-Chris
 
It’s an 04 and I believe in more recent years the R6 engine was used?

There aren’t many R6 boats out there and this is the only one with these older non common rail engines.

The R6 boats are 100-125k more
 
And I guess sometime back around then Brunswick did a lash-up with Mercury and Cummins, so that would have affected engine availability in various Sea Ray models. Which would maybe speak to why QSM-11s begin showing up in some models, or the newer higher-horsepower versions of the QSCs...

We have a dock neighbor in a Viking express-style boat -- late '90s, I think -- with MANs. Dunno which ones, but it seems like "800-hp" sticks in my mind, although if that's at all correct, it might just be a nominal figure... Anyway, I suspect he never did any injector work over the 15 years we were at that marina. He might not even know what an injector is...

Can you change injectors yourself? Or... Can you remove for testing, replace if good, yourself? Or... Can you remove for testing, even if you have a tech put them back in, or replace them? I know much of the maintenance cost is labor...

-Chris
 
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And I guess sometime back around then Brunswick did a lash-up with Mercury and Cummins, so that would have affected engine availability in various Sea Ray models. Which would maybe speak to why QSM-11s begin showing up in some models, or the newer higher-horsepower versions of the QSCs...

We have a dock neighbor in a Viking express-style boat -- late '90s, I think -- with MANs. Dunno which ones, but it seems like "800-hp" sticks in my mind, although if that's at all correct, it might just be a nominal figure... Anyway, I suspect he never did any injector work over the 15 years we were at that marina. He might not even know what an injector is...

Can you change injectors yourself? Or... Can you remove for testing, replace if good, yourself? I know much of the maintenance cost is labor...

-Chris

LOL. I’m sure there are plenty of engines out there running with severe neglect and they run just fine.

This MAN service thing, especially the injectors, is like instilling the fear of god into you.

I totally get it, a bad injector can ruin a piston and quickly become a 40k problem.
 
Maybe I'll get blasted for this, but I wouldn't be changing injectors every 2 years. If the engine runs well and you don't notice any change in temps, boost, or smells.... Chances are they are fine. Change your filters at double the frequency if concerned and carry 1 or 2 spares if it makes you feel better.
 
Maybe I'll get blasted for this, but I wouldn't be changing injectors every 2 years. If the engine runs well and you don't notice any change in temps, boost, or smells.... Chances are they are fine. Change your filters at double the frequency if concerned and carry 1 or 2 spares if it makes you feel better.

Agree. Issue here is this boat is a 2004 with no history of injectors ever being looked at, same for A1 and A2 service....no record. All this adds up to 25k....and who knows what else they may find once they get in there.....turbo....exhaust manifold....elbows.....etc.

I'm concerned the 25k estimate may quickly become 35k in actual work.
 
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