Princess v55, 2000, MAN engine 800hp, hammering noise, what is the cause?

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yossy

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Dear forum members,

I have gotten valuable advice from you before on several issues with my boat.

Listen to the sound from the attached video. What is causing this hammering noise? The engine? The shaft?

https://youtu.be/h_RWgNJ9jQs

When the boat is running at 7 knots and I put the starboard engine in neutral the hammering noise stops immideately. The starboard engine is still at the same rpm, 600, but no hammering noise. Can this be the engine or is it something with the gearbox? Or what can it be? Advice much appreciated in trouble shooting this.
 
Still there a bit in N for me .

Sounds very noisy the tappets need checking and adjusting .Thats a side observation and leads me to question the service history ?
Could be related to a valve or broken rocker .Would need to put a stethoscope on each rocker box / valve cover

I can hear the hammering to a lesser extent in N it’s does not completely go .
In a elimination of engine vs gearbox .

Even in gear at tick over ( 600rpm ) there’s a tiny load around from memory 36% so the injectors are made to squirt more fuel in to turn the shaft and spin the prop and push the boat even at 7 knots .

So that’s pointing to a stuck open or damaged injector , again stethoscope will identify which cylinder .

Need a bit more background info .

1-What’s it sound like at higher rpm s ? Did you try it ?
2- In N at higher rpm ?
3- Also with the boat running ?

4- Is this after a good blast out at sea ?
5- Or start up first early season run out ?
6- hours
 
yossy said:
Dear forum members,

I have gotten valuable advice from you before on several issues with my boat.

Listen to the sound from the attached video. What is causing this hammering noise? The engine? The shaft?

https://youtu.be/h_RWgNJ9jQs

When the boat is running at 7 knots and I put the starboard engine in neutral the hammering noise stops immideately. The starboard engine is still at the same rpm, 600, but no hammering noise. Can this be the engine or is it something with the gearbox? Or what can it be? Advice much appreciated in trouble shooting this.
Click to expand...

It’s transmission related , could be the flywheel drive plate breaking up .
Are you on ZF or twin disc gearboxes?

Check around the flywheel housing for small parts of rubber , when the coupling breaks down small parts are thrown out .

Engine sounds ok to me , most V engines sound rough at idle , it’s difficult to represent sounds on a phone recording I’ve tried it many times .
Sound is just bouncing around the engine room .

If your are unsure get MAN to look as you could save yourself a fortune if it’s serious before it goes bang .
 
As VP pointed out when he surveyed the engines on my boat the drive plate on the port TAMD41B was rattling. When started and at idle it rattles but as soon as put into gear it goes quiet.
He said it may last or may not but so far so good!
 
volvopaul said:
Engine sounds ok to me
Click to expand...
+1.
I've got exactly the same stuff (D2848LE403) in my boat, and I struggle to understand what is the hammering noise you are mentioning.
In fact, I'm puzzled by the fact that (as I understand) the sound of the other one is very different - can you post a similar video for comparison?
If I should be picky, the background whistle is possibly a bit louder than in my engines, but I don't think that's what U R concerned about.
BTW, these engines were typically mated - though I don't know if it's true also for your boat - to the ZF 350 g/box, which has an outstanding reputation for being bullet proof.
I'd be very surprised if the problem (if any) should have something to see with it.
 
PowerYachtBlog said:
The pumps on those 800hp if I remember well should be all mechanical. So they usually need a set up in around 1000 hours.
Click to expand...
No way, W.
I just replaced the injector nozzles in my engines at 1500 hours, and when I asked the very reputable Bosch service which did the job if it would have made sense to bring them also the pump for a check, they had a big laugh.
Btw, the pump is right inside the engine "V", and can only be accessed after removing the aftercooler - which I also did, hence my question to the Bosch chap.
But as I said, his strong recommendation was to not fix it if it's working, for at least another 1500 hours or so.
 
MapisM said:
+1.
I've got exactly the same stuff (D2848LE403) in my boat, and I struggle to understand what is the hammering noise you are mentioning.
In fact, I'm puzzled by the fact that (as I understand) the sound of the other one is very different - can you post a similar video for comparison?
If I should be picky, the background whistle is possibly a bit louder than in my engines, but I don't think that's what U R concerned about.
BTW, these engines were typically mated - though I don't know if it's true also for your boat - to the ZF 350 g/box, which has an outstanding reputation for being bullet proof.
I'd be very surprised if the problem (if any) should have something to see with it.
Click to expand...
It’s not the gearbox it’s the driveplate that breaks up .
 
Another vote for the drive plate. It’s definitely not tappets. That’s a big piece of metal knocking against another. Get a length of wood broom handle and press it against the engine at different points with your ear on the other end. Loudest sound is closest to the source.
 
MapisM said:
Yup P, I got your point, and I don't disagree with it.
My g/box comment was just generic.
Click to expand...
The ZF 325 and 350 are ok boxes , it’s the 280 that’s the weak one .
Driveplate break up usually goes on until death , it can only be heard when the load is taken off it , as in this case I’d say .
Obviously stand to be corrected if the OP gets to the bottom of it .
 
Yossy, if you don't mind a small O/T, have you got the engine oil temp in your dashboard?
If yes, what sort of numbers do you see once warmed up and at cruising speed?
I'm particularly interested to this specific engine model, but I'd appreciate an indication also from anyone else with MAN engines.
TIA!
 
volvopaul said:
The ZF 325 and 350 are ok boxes , it’s the 280 that’s the weak one .
Driveplate break up usually goes on until death , it can only be heard when the load is taken off it , as in this case I’d say .
Obviously stand to be corrected if the OP gets to the bottom of it .
Click to expand...
Hang on This is the other way round , pronounced hammering in D , first click staying at tick over with a load on . .
Op claims it goes in N , but as said it sounds still there to me but quieter on the vid .Take your point about sound recording on a mob in the engine room .

I thought about a drive gear from something like oil pump or fuel pump .Cant see a change with the oil pump from D to N , but maybe as event tick over loads it 36 % it could be fuel pump related .
 
MapisM said:
I've got exactly the same stuff (D2848LE403) in my boat, and I struggle to understand what is the hammering noise you are mentioning.
Click to expand...
For the records, I re-listened the video on my PC (my previous comment above was based on what I heard on a mobile device), and now I understand what we are talking about. Definitely not something I ever heard with my engines.
And in principle, I can see why the driveplate can be the culprit, but my ears and experience are not good enough to confirm nor deny that.
 
Thank you all for very valuable input Portofino, volvopaul, Montemar, Poweryachtblog, Mapism, and kashurst.

So Portofino you heard also the hammering in the neutral. So now I have been down to the boat and recorded the sound with only the starboard engine running in Neutral with 600 rpm and 950 rpm and 1700 rpm. You see the links below. It seems to me now when I listen like this that the hammering is definitely there also in neutral which would then mean it is engine related like Portofino was suggesting. To me it actually seems the hammering is most pronounced when at the lowest rpm? Or what do you think when you see the videos?

Some more info: Engine hours -1000. When I bought the boat MAN technicians said the injectors needs to be serviced. For different reasons, only the injectors on port engine have been serviced.

So I'm thinking, based on what you have all said and suggested, and what I now hear from the new video, is to get the injectors out and service them and se if that is the cause of the hammering sound? Before this I have had no problems with the starboard engine and this new sound came on pretty much the first trip in this season.

And yes I hear you when you say that I can listen with something connected to the engine to locate which cylinder is causing the sound, but as I should service all injectors anyway I might take them all at the same time.

Does this sound as a logic first step? An that gear box etc is ruled out as I hear the sound now in neutral so clear.

600 rpm
https://www.youtube.com/watch?v=by2NtHGTyyk

950 rpm
https://www.youtube.com/watch?v=0_gvljDpzEE

1700 rpm
https://www.youtube.com/watch?v=PuIeBtCyFVw


Rgds / Yossy
 
yossy said:
It seems to me now when I listen like this that the hammering is definitely there also in neutral which would then mean it is engine related like Portofino was suggesting.
Click to expand...
Not necessarily.
Volvopaul will correct me if I'm wrong, but I believe that his driveplate suggestion still stands even if you hear the hammering with the gearbox not engaged.
In fact, if that would be the noise source, I think it makes perfect sense that it becomes louder when under load.
I just had all the injectors serviced (at 1500 hours, btw) after investigating the subject extensively, and nothing of what I was told points in the direction of any weird noises, in case of faults.
I will revert (and hear your videos) asap - I just can't stand typing a lot on mobile devices... :ambivalence:
 
Drive plates can make a noise if breaking up in N .
Stethoscope or pseudo stethoscope about as suggested to find the exact location .
That’s the ‘logical first step “
 
Last edited:
OK good. Will do the stethoscope now in the morning. When I listened closer without stethoscope yesterday it felt as the sound was coming from the central part of the engines. But will see now with this better method if I can locate it :eagerness:
 
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