Maintenance on a MAN D2840LE402 diesel engine.

[BartW]

Since we purchased our (2nd hand) boat 2 years ago, the engines ran 360 Hrs (approx. 2500Hrs in total).
One season before we bought her she has had new injectors, (I’ve seen the invoice and the old parts)
and just before we got her she had a thorough maintenance from MAN service.

Last winter, 200Hrs ago, we did a basic maintenance ourselves and halfway summer I did a extra replacement of the fuel filters.

Last season there were no special nor worrying observations on both engines, they are running smooth, no unusual smoke, normal temp’s, etc …

So we want to do another maintenance this winter by ourselves, according the maintenance manual which say’s: Replacing Air filters, Fuel filters, Oil filters, oil, Checking belts and observe all hoses and screws;
one stop solenoid and one throttle control needs some TLC,
I'm not going to replace the cooling water in the closed cirquit, level was OK.

Is there something else that could be done precautious ?

I’ve seen some pictures from contaminated heat exchangers on here,
would it be worth opening, inspecting cleaning these ?

how about the Turbo's?

Any advice is welcome.

 

[volvopaul]

Since we purchased our (2nd hand) boat 2 years ago, the engines ran 360 Hrs (approx. 2500Hrs in total).
One season before we bought her she has had new injectors, (I’ve seen the invoice and the old parts)
and just before we got her she had a thorough maintenance from MAN service.

Last winter, 200Hrs ago, we did a basic maintenance ourselves and halfway summer I did a extra replacement of the fuel filters.

Last season there were no special nor worrying observations on both engines, they are running smooth, no unusual smoke, normal temp’s, etc …

So we want to do another maintenance this winter by ourselves, according the maintenance manual which say’s: Replacing Air filters, Fuel filters, Oil filters, oil, Checking belts and observe all hoses and screws;
one stop solenoid and one throttle control needs some TLC,
I'm not going to replace the cooling water in the closed cirquit, level was OK.

Is there something else that could be done precautious ?

I’ve seen some pictures from contaminated heat exchangers on here,
would it be worth opening, inspecting cleaning these ?

how about the Turbo's?

Any advice is welcome.

Various man engines I've come across seem to fail from piston overheat, more in full planing performance boats, that may have in the past been neglected on service and check version of the cooling system. I'd be running some checks at full throttle and recording the attained temperature , compare each engine though sea water temps this time of year will help with cooling where in the summer months its a different story. The main problems will be higher sea temp will be the charge air running higher which causes higher temperatures of the combustion air, in turn can overheat the pistons, also the heat exchangers can partially block up reducing there capacity, if the oil coolers are cooled by the closed water circuit then the internal water has a bigger job to do, hence this puts more pressure on the heat exchangers. If in doubt , and I know your a keen owner to keep things right then I'd be taking a look at the ends of the tube stacks.

 

[BartW]

Various man engines I've come across seem to fail from piston overheat, more in full planing performance boats, that may have in the past been neglected on service and check version of the cooling system. I'd be running some checks at full throttle and recording the attained temperature , compare each engine though sea water temps this time of year will help with cooling where in the summer months its a different story. The main problems will be higher sea temp will be the charge air running higher which causes higher temperatures of the combustion air, in turn can overheat the pistons, also the heat exchangers can partially block up reducing there capacity, if the oil coolers are cooled by the closed water circuit then the internal water has a bigger job to do, hence this puts more pressure on the heat exchangers. If in doubt , and I know your a keen owner to keep things right then I'd be taking a look at the ends of the tube stacks.

thanks for the advice Paul,
I'm hesitating to punish these old machines and driving them at full throttle,
I've done that only ones, that was during the survey.

The engines have been driven quite hard in their previous live by former captains.
but I avoid to go over 2000RPM (max RPM of these engines is 2300)
Last summer we sailed a lot of the time at displacement speed, 1000RPM.

perhaps I could do full throtle just a few minutes for the temp measurements.

I have a infrared temp measuring gun, and compare regulary during navigation the temp between different parts on SB and P engine, just to see if it's all equal / normal.

would be interesting to do some temp measurements now (in winter) and in summer, and perhaps also before and after cleaning the heat exchanger (if its dirty and needs cleening)
Its easy to open one side, will do that for inspection, as per your advice.

Oh I forgot to mention that I will also replace the impellors,
didn't do that last year, as they were still impeccable.

The MAN's you've worked on, where these 2840LE402 (V12, 1100HP) ?
actually all people I spoke with who know these engines confirm they are reliable beasts.
so far I'm happy with them, touch wood.

thanks for posting !

 

[MapisM]

perhaps I could do full throtle just a few minutes for the temp measurements.

Yep B, I really don't think you are taking a big risk by doing that, particularly with winter temperatures, as VP said.
It would be interesting also to record ALL the relevant temperatures while running at WOT (raw water, cooling water, oil, air inside and outside the e/r).
Aside from comparing the two engines, these numbers might also come in handy if and when you will want to see the difference in a hot summer day, or also after cleaning the heat exhangers.
And since you've got the i/r gun, it would be interesting to check also the main parts (turbos, manifolds, exhaust pipes) with it.
But don't forget some hearing protection!

 

[BartW]

And since you've got the i/r gun, it would be interesting to check also the main parts (turbos, manifolds, exhaust pipes) with it.

yes you're right, recording all temp data would be usefull for future use / investigation and comparison.

you wake up early, have you recovered from jetlag

 

[MapisM]

you wake up early, have you recovered from jetlag

LOL, funny you mention it, for some reason we suffered MUCH less going 10 hours backwards than 10 forward.
I'm actually used to that with a lower difference, as the typical 6 hours between CET and US EST.
But I would have thought that getting closer to a 12 hours difference, it would have been more or less the same travelling W or E...
Anyway, more than the jetlag, the problem is now the backlog of all pending matters...
I'm probably going to Lofrans for those checks before the end of this week, anyhow!

 

[BartW]

If in doubt , then I'd be taking a look at the ends of the tube stacks.

how about the intercooler,
I've seen worrying pictures from the intercoolers from Divemaster's DD's some time back.

In my case, they are right on top of the engines, easy acces, I could also have a look inside these.
untie-ing the screws might be a problem after 20years in position and all the temp changes
we might be doing more bad than good ?

 

[volvopaul]

how about the intercooler,
I've seen worrying pictures from the intercoolers from Divemaster's DD's some time back.

In my case, they are right on top of the engines, easy acces, I could also have a look inside these.
untie-ing the screws might be a problem after 20years in position and all the temp changes
we might be doing more bad than good ?

To test if intercooler is working run engine at wot, take reading with your ir gun on the inlet pipe from turbo and then after cooler on inlet manifold or as near cooler as possible , compare temp to see if cooler is working, you may get some figures from man for that, it has to be a good drop in temp but off the cuff I'm not sure what the difference should be, I've done many volvos in the past to check this.

If its an easy job to remove the pipework and covers then do it, probably the only time you will ever do it!

 

[BartW]

To test if intercooler is working run engine at wot, take reading with your ir gun on the inlet pipe from turbo and then after cooler on inlet manifold or as near cooler as possible , compare temp to see if cooler is working,

exactly the same advice I've got today from the MAN people at BOOT, thanks for the good advice VP!
It makes sense to open the intercoolers and the heat exchanger according MAN. They normally advice to do that after 1000 or 1200 hrs iirc.

Another test they advice (when looking for the state of the engines) is to look in the cylinders with a small camera,
but there is only a limited number of engineers who can do that, and make correct observations and conclusions according MAN.
They can offer that service.