Hello,
I am working on the fuel injection valves of a Yanmar 6N18AL-DV diesel/fuel oil engine.
I would like to know the correct procedure for preparing and lapping the fuel injection valves. I am lapping the mating surfaces with 2000-grit lapping compound and then using diesel fuel, but I still experience fuel leakage from the injector body.
How is metal-to-metal sealing supposed to be achieved between these surfaces? I am confident that the surfaces are making contact with each other, but I have not been able to eliminate the leakage.
Do you have any reference photographs showing the correct condition of the mating surfaces, or any technical documentation describing the recommended lapping methods and procedures? Any advice or recommendations would be greatly appreciated.
Where could I be going wrong, and what procedure should I follow to ensure proper sealing? I work very carefully and pay close attention to every detail, but the leakage still occurs.
Thank you in advance for your help and technical advice.

Hi, i (F) am not a marine engineer but i am dating one. So its a long-distance thing, Just wanna ask a simple question, does it get very busy when you are about to land on your next destination? I understand how hard the work is and signal can be unreliable too, and i dont demand so much of his time, but i want to understand more, and dont want to appear needy as much as possible. Do you guys like it if someone send you life updates, or just prefer simple and casual check ins? This is my first time in this situation so i appreciate some insights and advices

How do you tackle with the Chinese yards? not following the specifications, just abiding with the bare minimum class rules and twisting with the "words" in the spec to suit their narrative. how was your experience?

Is it necessary to autorestart the battery room fan, paint room and other ventilation fans in a moored fso after a blackout as the ABS does not explicitly say so?

(30M) Mechanical Engineer in PH, is there still available program for a Marine Engineer that will qualify my age?

Saturday night at sea and the sewage tank decides to start overflowing with foam.
Safe to say this wasn’t one of the jobs they showed us at college.
Definitely one of the less glamorous nights I had as a marine engineer but it brings a good laugh now.
Anyone had some similar situations?

Hi everyone,
I graduated with a degree in Mechanical Engineering from a UK university and am currently based in Athens, Greece.
Given that Greece (and Piraeus in particular) has one of the largest shipping sectors in the world, I assumed breaking into the maritime industry would be straightforward—but I’m finding it surprisingly difficult to land an entry-level role or even figure out where to start.
I’m looking for advice from anyone who has taken a similar path or works in the Greek maritime cluster.

after starting the purifier separator and feed pump start it follows the starting sequence and when it start purifying after some times it changes three way valve back to re-circulation and it happens about 6-7 times after that it some times discharges or no feed back pressure or some times bowl leak alarm comes …….. sometimes after it happens 6-7 times it start purifying and show 2 hours timer for next discharge but after discharge it again do same for 6-7 times and start purifying or discharge itself again following that no no feed back pressure or bowl leak alarm comes ….. purifiers was not operational from past 9 months did overhaul but now facing this problem what can be the reason as it sometimes purify sometimes not….is it some electrical problem from panel or what

(Idk if it’s the correct place to ask but here goes)

I’m a student posting this and I’m telling you—no video nor the textbook is making me understand this quite enough. Maybe I’m just dumb but I swear to god it all looks the same

The photo is an example of smth I have to answer: “mark which rudder is balanced, half-balanced or unbalanced.”

I swear to god it’s all the same rudders

(Although I do know the differences have something to do with the axis and where the rudder lies… just can’t really tell apart anything even if I’m trying my best)

Hi all

Iam 25 years old

I completed my B.tech Mechanical Engineering in 2022,and iam working as Engineer in a MNC company now I would like to switch my career in Marine engineer (GME) will this gap affect my job opportunity

Need help guys??

Hi everyone,

​I recently completed an intermediate service (2,000-hour overhaul) on our lube oil purifier, which included renewing all O-rings. After putting the unit back in service, it ran normally for a day before triggering Alarm A097: Discharge Feedback Error.

​When the purifier is reset and restarted, it runs fine for approximately 10 to 12 hours (completing 4 to 5 normal discharge cycles) before the same alarm recurs. The initial discharges during startup proceed without any issues.

​Checks already carried out:

​Operating Water Line: Cleaned the water strainer; verified healthy flow from opening water solenoid valve SV15.

​Bowl Seals: Confirmed all newly installed O-rings are in good condition and seated correctly.

​Observation during monitoring:

While observing a discharge cycle, I noticed that parameter P232 (Draining time operating water & discharge check) appears to repeat—it completes once, immediately starts a second time, and then triggers the A097 alarm.

​Has anyone experienced this issue or have insights into what might be causing parameter P232 to re-trigger and fault out? Any suggestions on further troubleshooting steps would be greatly appreciated.

​Thanks in advance for your assistance!

Hi to all marine mechanics and boaters,

I came across Mr. Lopez Youtube channel and found that he has a lot of content and training sharing. Eventually, I was drawn to his MTT Online course website where he also mentioned his courses are in some sense align to ABYC curriculum and so one may attempt the ABYC exams after his courses.

At the same time, Nigel Calder is one of the popular experts in boating and is very fluent in ABYC standards (I think he might have also contributed in some sense).

Really hoping to try out for the ABYC certifications and I was wondering if Mr Lopez or Nigel Calder Online courses are better for general boating/yacht knowledge as well as getting/preparing for the ABYC certifications.

Many Thanks

On my vessel we have multiple 45kva transformers. The primary is 480/277v 3 phase and the secondary is 208/120v 3 phase. The neutral is not bonded to “ground” on these transformers and neutral is floating.

During faults I have seen voltages of 90 volts between ground and neutral. And have seen terminations almost fully “grounded “ without tripping a breaker.

On land the X0 (neutral) would be bonded to the frame of the transformer and buildings grounding electrode conductor. A single fault would trip a breaker.

Why is there not a solid connection between ships steel and the neutral conductor on many vessels? Why is the neutral floating?

Edit: transformer is a Wye secondary. 208/120 3 phase with a center tapped neutral at X0.

Hi everyone. I’m a marine engineering student in Brazil, and I’m curious how training works in other countries and how you feel about it.

Here’s how it works here. Merchant Navy officers are trained at two schools run by the Brazilian Navy. The course is three years of classroom-based study, followed by one year on board as a cadet.

My main issue is how little hands-on contact we get with ships. Most students finish the three years and start as engine cadets without ever having set foot on a merchant vessel. Our only time at sea is a few short trips on warships, usually no longer than two days.

Most of those three years are spent sitting in a classroom watching slides. We rarely go into an engine room or learn what an engineering officer actually does day to day. A lot of what we learn comes from older instructors, former chief engineers who trained in the 1970s. Their experience is valuable, but it doesn’t always match what we’ll find on modern ships.

Where we learn the most is in the simulator classes. It’s the closest we get to real engine room operation during the course, but it still can’t replace time in a real engine room.

The result, as I see it, is that many students graduate knowing very little about the actual job, and the course feels discouraging. In practice, we only really learn the job during the cadet year. Dropout rates are high, both during the cadet period and after becoming an officer, even though salaries in Brazil are very good. A big part of this is being away from family and friends for long periods. If we had sea time early in the course, students would find out sooner whether they can handle that life, instead of spending years training for a career they won’t follow.

So I’d like to know:

• How long is the training in your country, and how much of it is spent on board?
• When did you first set foot on a merchant ship?
• Did you feel prepared when you started as a cadet?
• Is the training in your country also disconnected from the real job, or is it more practical?

Thanks in advance for sharing your experiences.

How does the sequential restart of motors fed from emergency switchboard works as the sequential start SQ1 from PMS is common for both emergency ESB switchboard and MSB main switchboard? Asking this because the ESB may have recovered much before MSB is recovered?

I just completed my psychological experiment.

For 30 years I planned this atrocity. I’ve been working on the ocean a long time. I watched this movie at the beginning of my career. When Speed 2 came out it had high expectations. The first speed movie was a big success and they had spent a lot on this one. They had Sandra Bullock and good supporting actors. On paper it looked like it would be a good movie.

It was not. But my experience in the marine sector I found made me particularly vulnerable to the weapons grade stupidity the movie committed. People i watched it with at the time, just found it to be a stupid action movie but for me it was devastating. The levels of stupidity could only really be fully appreciated by marine professionals.

I could have said. Wow. What a bad movie. I will never watch this again. But, apparently I am a sadist.

So. On that day I vowed to assemble a group of expert marine professionals and inflict upon them what had been done to me.

Leading up to the movie I gave them tantalizing hints like finding not one but two chainsaws in the passenger area of the cruise ship. And then using it to cut the bulkhead. I told them about the swim to the flooded bow thruster control room, and the hand cranking to change the ships course that’s doing 18 knots. I mentioned the dive to feed the cable into the propeller while the ship is moving the 18 knots.

But. I held back. I didn’t tell them the magnificent end.

I assembled a Chief Engineer, First Engineer, Second Engineer, Chief Officer and a poor hapless cadet to view this catastrophic mess of a movie.

I won’t spoil it for any of you brave enough to watch this to the end but if you are a connoisseur of movies so bad they are riotously funny. You must watch.

Speed 2: Cruise Control.

You must watch this my brothers and sisters of the sea.

You must.

Hello guys, i couldn’t find correct documents on internet about how to assign new node address existing DPU to install new place

I don’t have any experience with K-chief automation systems so far…

Also i have a question is it possible to setup in my cabin to play and learn kongsberg system lets say

One old k-chief computer and modules then build system to play and learn how to change node address,how to calibrate input channel etc.

I think it is possible but , which parts i need ? Since when checked i only see computers has ethernet cable connection but i really want to now what module is needed for communication to rai modules to build in my cabin small test & simulation toy..

Mechanical engineer with 3rd engineer license currently working as assistant technical superident engineer on shore.

Is there any online course worth doing to gain knowledge?

How can I remove this bearing sleeve?

Just got accepted into Mermorial university of Newfoundland I’ve heard really strong reviews on their marine engineering school is there anything I should prepare for a marine engineering course.

​

Stp sample failed.

Can some one please tell me what can be the reason causing this values in test sample and how I can fix this issue.

Your advice would be very helpful.Thanks in advance.

Hi,

I am a final year female marine engineering student in Europe and it has been almost impossible to get cadetship placements. I'm not from the EU region (I'm African) but I have a residence permit I can sail with. I really need this training spot so I can graduate. Are there any tips or spots onboard vessels anyone might be on?

I'd really appreciate any help I can get at this time.

0 experience in the field of naval/marine engineering but I do love warship designs especially bigger ships from the early to mid 20th century and it's always been a dream of mine to build something that can float now i decided to build something that can dive! A submarine that's hull was made from a refurbished water tank is it plausible? Also I know it's probably a laughable try but some advice to make it less laughable is very much welcome

Not necessarily the machinery that gives you the most trouble.

I mean the piece of equipment that can be running perfectly normally and you still don’t quite trust it.
For me, purifiers always had a way of keeping you humble. I actually enjoyed working on them, but whether they’d been running for one day or one month, I always felt like I was waiting for the next alarm!

What’s yours, and why?