Why do intercoolers on my MAN engines need cleaning every 2 years?

[Portofino]

Me too
Here's some info
http://www.manengines.com/file_download/6/MANWhichEngineOil.pdf

 

[Deleted User YDKXO]

Thanks pan

 

[Portofino]

Pages 8'9'10 ref to "M3277". Spec and oil fouling
http://www.mancraft.no/Data/Sites/1/downloads/fuelslubricantsandcoolants.pdf

Here is the M3277 - contradictory ? Is this for trucks ? None marine ?
http://blog.truck-center.ru/wp-content/uploads/2012/01/M3277.pdf

 

[Deleted User YDKXO]

The yard has sent me these photos today.

The first photo is of the heat exchanger on the s/b engine. I'm not sure whether this constitutes bad fouling or not. Obviously it is difficult to tell until the bores can be inspected.

Anybody care to comment? Either way I've told the yard to get on with it and clean everything

And this is a pic of the gearbox heat exchanger. Surprised that so much debris got through the strainer

And this is a pic of the seawater intakes on the underside of the hull

Lastly, I experienced small freshwater coolant leakages from both engines on a regular basis last season particularly after long passages - see pic below. The coolant appears to come from the header tank overflow pipe. I have complained to the dealer who supplied me the boat (San Lorenzo) under their warranty and all they say is that they can find nothing wrong so it must be due to overfilling at the beginning of last season.

Anyone think that this freshwater coolant leak might be caused in any way by poor heat transfer in the heat exchangers?

 

[BartW]

waw ! surprising pics Mike,
makes me conclude that it DOES make sense to inspect heat exchangers internally on a regular base,
have to inspect my gearbox oil cooler now !

regarding the leaking cooling liquid,
I believe that the concensus was that this is due to overfilling, typical on the MAN cooling cirquit
On BA, the leaking fluid disappears in the bilges of the engine room, (its just fresh water without any addition)
and I can also add some water untill completely full, after almost every water level inspection, (after using and running the boat for a while)
but If I don't add, the level doesn't go below a certain level, that still is OK,
I would advice you to do the same, don't refill, and inspect if the level doesn't lower below a certain acceptable level, then you'r ok,
I'll asc my MAN man when I meet him next week what he thinks about that.
Do you have it on both engines ?

 

[Deleted User YDKXO]

Do you have it on both engines ?

Don't know yet!

 

[pan]

Clearly looks like some cleaning work was required, we haven't had any issues with leaking fresh water coolant, although I am aware that it is very important to ensure the header cap seals are in good order (we carry 2 spare caps) the MAN system is pressurised & it's vital there is no leakage.

Below are some other photos from the engineers which illustrate the work that was needed on our engines, have included one of the diagnostic computer readings they also emailed me, these were very useful as they showed the date & time of any alarms from the MMDS system from day 1, I intend to ask for these for ongoing service work, as they provide a good record for future re-sale & identifying any potential issues.

check your water pumps...there was some leakage from both ours!

 

[Deleted User YDKXO]

Clearly looks like some cleaning work was required, we haven't had any issues with leaking fresh water coolant, although I am aware that it is very important to ensure the header cap seals are in good order (we carry 2 spare caps) the MAN system is pressurised & it's vital there is no leakage.

Thanks, pan. That was my first thought too. I have replaced both header caps already and the leaks continued

 

[MapisM]

And this is a pic of the gearbox heat exchanger. Surprised that so much debris got through the strainer

Indeed.
Weird as it might seem, I would even dare guessing that those weeds actually grew inside the heat exchanger, during extended periods with engines not running...
...but what do I know?

 

[Deleted User YDKXO]

Indeed.
Weird as it might seem, I would even dare guessing that those weeds actually grew inside the heat exchanger, during extended periods with engines not running...
...but what do I know?

Are you suggesting I have my own secret cannabis weed farm in my heat exchangers?

Of course the next question in my mind is what the seawater circuits in my generator and aircon units look like. Jfm's idea for a freshwater flushing system is looking like a very good one

 

[jfm]

Of course the next question in my mind is what the seawater circuits in my generator and aircon units look like. Jfm's idea for a freshwater flushing system is looking like a very good one

Yes indeed. And I will be adding a litre of garden weed-killer each time I do it now!

(BTW Deleted User, I am the mere spanner monkey here. It was MapisM's idea. :encouragement::encouragement: )

 

[MapisM]

I am the mere spanner monkey here.

LOL, that's a massive understatement, if I've ever seen one.

Though you are now making me think of a possible addition to the fresh water flushing system: a small glycol tank, to mix to the fresh water while flushing.
Almost like a full winterization on the fly!
And I would think it should work also as a weed killer, on top of inhibiting corrosion....

 

[Robg71]

Indeed.
Weird as it might seem, I would even dare guessing that those weeds actually grew inside the heat exchanger, during extended periods with engines not running...
...but what do I know?

Its actually quite common.
We have big alfa laval plate coolers that get stripped every six months to remove mussel growth and other material... Stuff too big to have actually got in there, so only conclusion is it grows.....

 

[Bandit]

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Picture two shows substantial blocking of the tubes, needs cleaning with Rydlyme as brick cleaner is too harsh.

Picture three shows weed on the outside of the tubes, the seawater is normally on the inside of the tubes?? Also the tubes are very pink, possibly showing attack from cathodic corrosion, it should be freshwater and coolant on this side?

The inside of a cooler is normally protected by anodes, what condition were they in?

Picture four shows like scale build up requiring Rydlyme circulation.

Charge air, main engine and gearbox coolers on all modern high performance engines, require dismantling every few years inspecting and putting in a bath of Rydlyme to remove lime scale. Circulating Rydlyme through an engine every year or two will als help enormously.

 

[pan]

Thanks Bandit appreciate the input, actually in pic 3 the engineers reported this was not weed, but some sort of metallic shavings, which we never identified where they came from (could only assume debris from engine build!) and certainly had us scratching our heads. The anodes were quite corroded and have been replaced, which again brings us back the necessity of the scheduled MAN recommended cleaning.

 

[Latestarter1]

Thanks Bandit appreciate the input, actually in pic 3 the engineers reported this was not weed, but some sort of metallic shavings, which we never identified where they came from (could only assume debris from engine build!) and certainly had us scratching our heads. The anodes were quite corroded and have been replaced, which again brings us back the necessity of the scheduled MAN recommended cleaning.

Extremely unlikely to be from engine build, more likely to have been left in by charge air cooler manufacturer. Well worth giving MAN the heads up.

 

[pan]

Thanks latestarter1, I didn't actually mean during the block build, more likely the cooler manufacturer, but would have expected MAN to have picked up on it assuming they actually put the whole thing together! Knowing engine manufacturers, they would immediately deny this debris was there on build and of course 'the user must have deliberately put the material in'... the engineers were MAN authorised and didn't really want to investigate further. Anyway I am just happy we did the work and can enjoy the boat confident in the engines, like to think of it being a pleasure rather than having to do battle with everyone.

 

[Deleted User YDKXO]

Just to finish this thread off, I had heat exchangers, charge air coolers and gearbox oil heat exchangers inspected and cleaned on both engines. The yard reported that the charge air coolers were relatively clean and didn't need any work, the engine heat exchangers were OK but would have needed cleaning in another season but by far the worst items were the gearbox oil heat exchangers which definitely needed cleaning. It looks as if whoever last cleaned the engine heat exchangers omitted to clean the gearbox oil heat exchangers and its quite possible they've never been opened up since the boat was new. A heads up for anyone with gearbox oil heat exchangers

Either way, I'm glad I've had this done and feel confident that the boat can go another 2 or 3 seasons now without these items being opened up. And finally, the freshwater coolant leak seems to have stopped. Whether this is due to the engine heat exchanger being cleaned or simply due to the fact that the yard didn't overfill the freshwater coolant tank this time I don't know

 

[pan]

Good stuff, thanks for the heads-up Mike

 

[BartW]

thanks for the update Mike,
I'll have a inspection on my gearbox oilcoolers on my MAN's aswell

now you can sleep well regarding your MAN concerns