One MAN engine fails on last day end last trip of our summer holliday’s

Great news and timing Bart. Good luck with the final parts of this project. Has the "new" engine been dyno-ed or is it a case of fingers crossed that it develops the correct power?
 
Has the "new" engine been dyno-ed or is it a case of fingers crossed that it develops the correct power?

no unfortunately not dyno-ed,
no dyno setup available within 500km from where the boat is

we have to rely on the rebuyld and re-adjustment of the injection pump by Bosch,
and comparison tests with the performance of the "old " engine

we didn'd do long tests at 2000RPM, and no tests at max RPM, as the hull was very fouled
I'm not yet shure if the new engine needs a run in period at lo RPM,
we'll do another test at the end of the week after new antifouling,
 
Probably a good idea to vary the rpm during the first 10 hours or something, don't just sit at cruising rpm for 10 hours straight. Avoid low engine load too, not too much idling.
 
yesterday we did another sea trial, with clean bottom, and RPM meters working accurate on both engines,
and I'm pleased to report that the new engine works perfect !

after one hour cruising at slow speed, approx 1000 Rpm we increased her speed gradually, and both engines are running smoothly in sync.
we got the usual fast cruising speed, 20kn at 2000 RPM.
we even got to full throttle for a few minutes, and both engines reached 2300 Rpm max.
I'm really impressed that this new engine performes exactly the same like the old,
also smoke during start en during cruising, we could not see big differences !?
so all in all, I have good reasons to be pleased and satisfied !

next week they will nevertheless replace the injectors and vibrationwheel on the old engine,
and try to find the cause of the small water consumption on that engine.

thats all before the summer starts,
during the summer we will get experience with the engines,
ao performance, smoke, difference in fuel consumption, ...

This whole rebuild project has now reached a happy ending
if someone is interested I can post some more pics from during the project, etc..
I'll update this thread when new info comes up
 
+1 re. more piccies, of course!

next week they will nevertheless replace the injectors and vibrationwheel on the old engine,
and try to find the cause of the small water consumption on that engine.

On this topic, forgive me if I'm teaching grandma to suck eggs, but did you check if the cooling liquid level stabilizes after a while if you do NOT refill it again?
I'm asking because I recently discussed the MAN closed cooling circuit with the guy of the yard where Deleted User had his boat serviced.
They aren't MAN officially authorized, but they are for both Cat and VP, and that folk has seen his fair share of most other blocks.
He told me that the it's not unusual for MAN engines to self-adjust to the right level by "spitting" (so to speak) a bit of liquid when, after being topped up, the engines are used for a while at operating temp.
And also confirmed me that sometimes he found such level - for reasons he couldn't explain - to be somewhat different, also between two identical engines installed in the same boat, position, etc.
So, if you don't experience any further level reduction after an initial leak (starting from the topped-up level), you could try to leave it as it is, without insisting in topping it up.
But of course, if it continues to go down, I reckon that it's appropriate to find the leak and fix it! :)

PS: while you are at that, in your boots I'd rather replace plain water (if as I recall that's what you had in the cooling system) with the appropriate cooling fluid.
 
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....He told me that the it's not unusual for MAN engines to self-adjust to the right level by "spitting" (so to speak) a bit of liquid when, after being topped up, the engines are used for a while at operating temp.
And also confirmed me that sometimes he found such level - for reasons he couldn't explain - to be somewhat different, also between two identical engines installed in the same boat, position, etc.
So, if you don't experience any further level reduction after an initial leak (starting from the topped-up level), you could try to leave it as it is, without insisting in topping it up.
But of course, if it continues to go down, I reckon that it's appropriate to find the leak and fix it! :)

That’s exactly the phenomen we have P. !
Last year during the long trip from Rome to Montenegro, I forgot for a while to check that water level alarm light, and have been sailing for several hours at planning speed.
Usually the warning light goes on just after a few minutes at planning speed.
That alarm light is on the lower helm station, and not upstairs,
There is no buzzer, so i have to go down to check that, and forgot to do so.
I do check water temp, and oil pressure regularly from where I navigate, and never had a issue with cooling water temp, always stable at 85°.

Also I have swapped the cooling water cirquit caps (with integrated overpressure valve) from both engines (2 on each engine)
But the issue remained on the same engine.

I discussed the problem extensively with Ilko today and yesterday during the sea trial (the problem occurred soon after we got 2000 RPM)

And for now he’s going to do the following:
- Put pressure on the cooling cirquit, and check if it holds this pressure (he has the tools to do that)
- Open the turbo’s and check for eventual traces of water leaks / corrosion
- Replace all caps from the cooling water cirquit on both engines.

From there we will see what comes up, and what’s next



in your boots I'd rather replace plain water (if as I recall that's what you had in the cooling system) with the appropriate cooling fluid.
In the “new “ engine ofcause there is the correct cooling liquid,
In the old engine he adviced just to keep the liquid in there
As we will probably give that engine a similar overhaul after the season (less massive and less expensive), so that both engines have the same “condition”
At that moment he will clean and rinse all parts of that engine, and after assembling put the correct fluid.
He advised not to waste money on cooling liquid until then
 
+
He told me that the it's not unusual for MAN engines to self-adjust to the right level by "spitting" (so to speak) a bit of liquid when, after being topped up, the engines are used for a while at operating temp.
And also confirmed me that sometimes he found such level - for reasons he couldn't explain - to be somewhat different, also between two identical engines installed in the same boat, position, etc.
So, if you don't experience any further level reduction after an initial leak (starting from the topped-up level), you could try to leave it as it is, without insisting in topping it up.
But of course, if it continues to go down, I reckon that it's appropriate to find the leak and fix it!

Yup, I experienced minor coolant losses from the MAN engines on my boat on and off during last season. In my case, the coolant was being ejected out of the overflow pipes from the header tanks. I had the engines checked out a couple of times under the warranty and again over the winter, I had the boat seatrialled with a MAN technician on board. I also changed the pressure caps. I never experienced an over temp alarm like Bart did though.

Everybody said the same thing; as you say 'they all do that, sir!'
 
I never experienced an over temp alarm like Bart did though.
Actually, B said that a level, not a temp alarm went off on BA. And that the temp is instead stable, in fact.
I'd definitely be more concerned by a temp alarm vs. a level alarm - provided of course that the cooling circuit is full, even if not as full as (in theory) it should be.
 
Actually, B said that a level, not a temp alarm went off on BA. And that the temp is instead stable, in fact.
I'd definitely be more concerned by a temp alarm vs. a level alarm - provided of course that the cooling circuit is full, even if not as full as (in theory) it should be.
Ah OK missed that
 
In my case, the coolant was being ejected out of the overflow pipes from the header tanks.

yes today I discovered that there were quite some "fresh" traces from (brown) cooling water spoiled on the engine block through one of the overflow pipes, that exits right above the alternator.
But this is probably normal, because I have refilled that header tank so many times until completely full.

on that engine I could fill each time approx 7l to 10l of cooling water untill completely full.
on the other (normal) engine I could top up about 2 to 5l (don't remember exactly as I fill it with a hose)
 
on that engine I could fill each time approx 7l to 10l of cooling water untill completely full.
on the other (normal) engine I could top up about 2 to 5l (don't remember exactly as I fill it with a hose)

Despite the leaks I never actually had to fill my header tanks last year because the level was always within a few cms of the top. It was a bit bizarre because there was a small amount of coolant escaping from each engine regularly and yet the coolant level never seemed to go down. Obviously I thought that was odd which was the main reason why I got the engines checked out 3 times. Anyway I just have to accept that this is a 'characteristic of these engines
 
Here is an update on the exciting story about our engine’s!

REMINDER;
Last winter and spring we had a total rebuild done, of one of our old V12 MAN engines,
The “new” engine was successfully sea trialed first week of june,

FUEL LEAK
After the sea trial, Right before I went back home to Belgium (Boat is in Montenegro) I noticed there was fuel in the bilges of the engine room, and I asked the MAN man Ilko, to take care of that during my absence,
A day later he called me that they pumped out about 200kl of fuel, and that they found the source; a not well fitted seal of a fuel prefilter of the genny
All good I thought,
But a few day’s later I got a phone call from the marine, telling me that there was fuel leaking out of the boat,
I asked Ilko to take care, and he immediately went to the boat,
The fuel level in the bilge was high enough to flow through a hole in the bulkhead wall with the utility room, and there is a automatic bilge pump…
After pumping out (in jerry cans) several hundreds of liters of fuel, the real source was found, a small crack in a fuel pipe from the rebuild engine, probably caused during take out / back in of the engine.
So now this was cured,
Luckily the marine didn’t make more complaints, as the local authorities are extremely strict on this kind of pollution. We heard several stories about high penalty’s.

MORE FUEL LEAKS,
We had agreed with Ilko, that some basic maintenance would be done on the “old” engine, in the remaining weeks right before our summer holiday starts
ao new injector nozzles,
and a basic inspection on the cooling water disappearing that was there already from before last season.
He didn’t found the source of the problem without disassembling a major part of the old engine,
and as a rebuild of that engine was planned for next winter, we decided to live with that for now.
Due to work commitments I could not go to the boat to inspect the work on the “old” engine

Immediately after first arrival for our summer holidays, on 1 July, when arriving at the boat, I started the engines for checking, and noticed som fuel leaks around the replaced injectors,
Apparently they didn’t do a decent test after replacing the injectors, but they came immediately to cure the problem.

We had to leave and sail from Tivat Montengro to Cavtat Kroatia, the same day, to collect my first guests (my mum and her friends)
And collect some equipment that my mate brought with my car, also in Croatia, to avoid customs passage to Montenegro with all this stuff.
Luckily Sailing towards Cavtat Croatia at planning speed in a hurry to be there before customs closing time 8pm, passed without a problem.
Arrived right in time to collect my mum and her friends the following morning
and the equipment brought by my friend, oa a nice chiny brand new SS 12mm anker chain !  
starting your holiday’s with that kind of stress is no good !


HEAT PROBLEMS
2nd or third day of the trip with my mum, I started to see abnormal high water temperature (>85*C ) and that was surprisingly on both engines,
Sometimes the “new” engine reached 90°C
We thought of all kinds of reasons, even the very high water temp this year in Croatia (29/30*C)
And also suspected electrical problems; did quite a few tests switching on different equipment / battery’s, etc…
But none of that could cure the intermittent high temp readings.
I didn’t have any mechanical temp gauges left in the engine room, both are broken, and my infrared temp gun got wet / was broken about a year ago,
So had no accurate info about the real engine temp’s
We continued our holiday / cruise with the boat

The following week, with other guests, during navigation, suddenly the new engine temp meter went over 100*C
I immediately set throttle at idle, and went looking in the engine room,
The new engine was completely sprayed with cooling liquid, so cooling water has come out under pressure.
I couldn't see where the water came from.
But now temperature got back to normal 83*C.
I refilled the cooling water of the new engine, and luckily not much water was out , we continued that cruise a few more day’s, but at poodle speed only, without a problem,
Back in homeport Tivat, we had a few day’s off before new guests (our kids) arrived, so Ilko spend the best part of one day, to disassemble and inspected the complete cooling system of the new engine, but couldn’t find a problem.
Then we went on sea trial, and only at planning speed with higher cooling water pressure, we could notice a water leak in one “NEW” hose,
so now we have found the source of the cooling water spray.

MORE HEAT PROBLEMS,
But the next day, when doing a long trip with the kids at planing speed, I could see again both temp meters going up and down, even above 90*C
After a phone call, Ilko came onboard with a temp Gun,
And pretty soon we discovered that engine temp on both engines was PERFECT,
So the problem was the reading, and then I discovered that all gauges move, when I touch one of the multipin connectors on the lower helm station dashboard,
actually these connectors had been moved some weeks before to re-arrange some cabling of the dashboard = storage room
Some contact spray, and fitting – refitting the plugs, cured the problem for now .We will replace these multipin connectors later in winter time
I kept the temp gun onboard to do regular and accurate temp measurements on different parts of both engines. (and compare both)
But for now we were OK with engine temps.

ELECTRICAL PROBLEMS
When we arrived at a overnight anchorage, bow thruster and winch didn’t have much power,
I discovered that the engine battery bank was almost completely empty,
The genny and battery chargers cured the problem, but during the night broke my head about potential reasons for this battery drain,
Either the charger didn’t work or there was a big load somewhere on the cirquit.
Some investigation in the morning showed that the chargers work when the engines run,
And no big load on the engine cirquit amp meter,
But while doing these tests, I discovered that all the engine guaches wiggle when I switch on the contact of the old engine,
And the volt meter drops a few volts,
But while doing these tests suddenly this wiggling disappeared, so probably the problem was / is cured. (it seemed that a relay contact was
cleaned)
There is only one possible load that I could think off, that could cause this problem, the “air preheat” cirquit that these engines have, and which we never ever use,
Only needed when you start the engines in extremely cold condition.
So to be sure, I disconnected the preaheat solenoid control cables on both engines,
This problem never came back

ANOTHER BIG HEATING PROBLEM
2nd day of the last week of out holls, we sailed for more then 3hrs at planing speed (2000rpm, 20kn)
In the past, the old engine looses cooling water after planing speed, until just below alarm level, but never lower,
During the trip I regularly checked engine temps with the temp, gun, all ok,
But after the trip, after cooling down, I could add substantially more cooling water in the old engine than ever before.

The following morning we sailed at poodling speed (1100RPM, 10kn) from Mljet to Korcula,
At that speed I didn’t give much attention to engine temps, (swmbo was helming) until almost halfway, the temp gauch on the old engine showed total overheating,
Dropped speed to idle on both engines, went in the engine room, and saw that the old engine, was completely overheated (smoke), and paint started to melt on some parts,
Switched off that engine immediately, continued our voyage on one engine, to Korcula / Lumbarda, where we anchored for lunch,
After lunch, engine temp was cooled down and I was able to open the cooling water reservoir, and poor water in it,
Cooling cirquit appeared to be completely empty,
After that I tried to start the engine, but it “blocked” immediately.

This is the end of this season, luckily we were in our last week,
We decided to continue for the remaining 5 day’s, no mooring in marina’s but staying on Anker, at that moment we were at about 100 miles from our home berth !
We don’t have a stern thruster, so its completely impossible to maneuver backwards or on a stern to mooring
Nevertheless swmbo proposed to practice such a mooring in Kobas, on a restaurant quay (more space, less spectators)
by bringing a long rope with the tender, from the boat’s stern to the quay, and pull the boat with the rope, in combination with one engine !
This worked quite successfully, so we repeated this procedure in Cavtat for a one night stay, and customs passage,
And one more time in Porto Montenegro, when arriving on our berth
The side mooring for customs in Zelenica Montenegro was no problem.

ANOTHER ELECTRIC PROBLEM
after sailing on one engine, during that first difficult mooring maneuver in Kobas we noticed that the engine battery banc became almost empty (which is normal as engine and alternator for that banc are not running)
No power on bow thruster nor anker winch,
So during the maneuver I had to run down to the engine room, to switch on the emergency battery banc parallel switch,
you can imagine the adrenaline at that moment ?
(fyi 99% of the stern to moorings in that region are done with use of the anker, no bow lines, this is to accommodate a big variation of boat sizes)

actually we did a few nights on anker with a “double” battery bank, 2 x 24V 640Ah !, so that the automatic genny start cirquit didn’t come in operation
usually that cirquit starts the genny / battery chargers around 6am)


SUMMERY
We had a fantastic 6 weeks holiday in Croatia / Montenegro, best weather “ever” >30°c permanently, seawater temp 29-30 degrees
The New engine is performing excellent, 150 hrs, 1000 nm
The cooling water issue on the old engine became worse, and during the last week, the old engine blocked due to overheating
so another rebuild is a obligation now, and already planned with Ilko
this thread is not finished yet !
 
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I sort of got adrenaline rush just from reading this... :/ Hang in there...!

sort of know what you mean, for me it was that sort of pit of the stomach "oh god" feeling....

Bart, running Blue Angel was never going to be a walk in the park, but you do have some lovely holidays aboard her. You've been through one re-build, so at least you know what round the corner. Good luck.
 
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