What Diesel Engine repairs should one know how to do?

[Perfect Ride]

As each engine make has a different set of weak spots I find the following very helpful. In fact helpful with all systems on a boat. Find a very good mechanic, based on reputation and years and number of times working on YOUR engine type. Ask them to do your first service on the engine and ask if they would mind you paying for an additional half hour for a Q&A. Here is a list of what I ask them:
1. What are the top five types of service calls you make?
2. What maintenance consumables do you use in a year on this system. Remember to ask about filters, oils, lubes and solvents for cleaning.
3. What parts do you replace the most?
4. What can be done to prevent the weakest links in the system?
5. Can you suggest any upgrades or changes that improve the system for our type of sailing?
6. What after-market items have you seen installed that improve the system? Where can they be bought? Manufacture/Model#?
7. Where is the best place to get parts if I am not in this region? Who are alternative providers?
8. How many of these specific systems have you personally serviced in your life?
9. What spare parts would they bring if to do your anticipated journey? Describe your journey both by location and duration.
10. What tools would you be sure to have to maintain and repair the system.
11. What custom tools do you use?
12. What manuals are available to mechanics/engineers for the system? Get numbers if possible, it will help in your search for free online PDF versions. Many engines will have three or more manuals: operators, service, electrical, installation... you can read these for tips on tools too.
13. What tricks are there for periodic maintenance?
14. What tricks are there for most likely repairs?
15. Where would you suggest I get the best prices for parts if not in your area? (It may be hard to get an honest answer here, but worth asking)
16. Have them look at your tools and offer suggestions on what is missing.
17. Who is the best technician in your business?
18. If I ever have problems would you mind me calling or emailing you with questions? For fee or free?
19. Can I have your (their) cell number / email if I have questions?

I find this a very helpful step for water makers, generators, etc.

[Puregravy]

Wonderful post. Thanks all. After having had to do an upper end rebuild on my volvo penta 2020b, noting the impact of back flow from a constricted exhaust mixing elbow I'd add checking and cleaning of that piece. I carry my old as spare and replaced it with a re-engineered stainless elbow with better flow. I carry an extra gasket and marine graphite paste and will check annually.

[rvich]

[Sailor 99]

Originally Posted by FabioC

As a related question for those of you who know how to do:
how did you learn? By trial and error? Did you have a friend who showed you? Did you hire a mechanic to show you? Did you take a class?

I have read a couple of the usual books on diesel engines, and I am at least familiar with the parts and their operation, but when it comes to actually performing some of these repairs, it is still challenging, especially on the parts that are very difficult to access, then you do not quite have the right tool, etc. Mechanics of course have figure it all out, but with trial and error the learning curve is steep...

It helps to be mechanically inclined but videos on how to do this stuff are all over youtube.



A lot of it is common sense. Get in there and work on them and it becomes clear pretty fast. I always had an issue with diesel engines could not wrap my head around them till I took the fuel system apart on one for repair. Easy peasey... Would rather work on them than anything else now.

But you also need the tools to fix all of this stuff.

A cruising sail boat should have 2 complete sets of screw drivers and the following list of tools, the boat is i mixed metric meaning some metric and some inch then double up all tools. Any European boat in the US for any amount of time is going to be mixed metric because metric is simply not available. If the boat was US build but has a new motor you can be very sure that motor is metric.

You need a complete socket set with ALL sizes from 5mm or 1/4 inch all the way up to at least 1 inch or 25mm. Both deep and shallow. Watch out here because these clown like to sell you a complete set in a nice box and then you find out you don't have an 11/16 socket because they were going for a price point.

You should have 2 complete sets of open end box end wrenches. Some times you need more than one of each sized to do the job.

You need a set of starter motor wrenches. 1 will do.

You need at least 1 perhaps 2 universal joints for each drive size for your socket sets.

I have a set of universal jointed sockets.

You need a hydrometer to test your battery.


You need at least 1 cat 3 multi meter.

I have a set of crows foot socket wrenches in both metric and imperial

You need pliers, at least a couple of different sizes of vise grips, side cutters, hack saws, needle nose plier in several sizes.

You need an oil filter wrench.

Crimping tools for wire repair.

That's a lot of tools and I have them all in both metric and imperial and maybe its over kill but I have had to replace the starter and when I did not have the right wrench I had to drive 20 miles for it. If your out behind some island an your start is gone, your not driving anywhere to get anything.

Ya I have a lot of tools. But then I can fix almost anything. Some things you simply can not fix without some of these stranger tools like the crows foot socket because you don't have a tool that can get in there. Especially on some older Perkins


Now you need to keep this stuff from getting rusty. So it all needs to get put in a few dry bags.

[Jef & Marin, Netherlands]

[QUOTE=Dark Horse

Do you have a way to catch the little bits if the impeller dies a horrible death. This can be essential. If you don't have this then you have to be able to take apart the entire cooling system to collect all of the impeller bits. This will require gaskets, O-rings and arms like Gumby to remove all of this stuff and clean it out. I am currently working on a solution for this and will post more if it works.

Dark Horse and others, lots of valuable advice. I would like to add this Tip & Trick: When all the impeller parts are in the system (mostly in the heat exchanger), you can get them out easily by backwashing. I did this by disconnecting the hose going from the heat exchanger to the exhaust elbow. And used the deck shower to backwash. The deck shower's head nicely fitted in the existing hose.
If you put a bucket below the water pump">raw water pump, with the cover off and the impeller out, the small impeller bits might be in the bucket instead of in the bilge. It is a wonderful sight to see them all in the bucket after such a small job.

With this trick you do not have to open the heat exchanger, this saves a lot of work.

[Rasselas36]

I have a service manual (Bible) for my Yanmar. Everyone should have a service manual for their engine, my opinion.

[Sailor 99]

Originally Posted by Jef & Marin, Netherlands

Do you have a way to catch the little bits if the impeller dies a horrible death. This can be essential. If you don't have this then you have to be able to take apart the entire cooling system to collect all of the impeller bits. This will require gaskets, O-rings and arms like Gumby to remove all of this stuff and clean it out. I am currently working on a solution for this and will post more if it works.

Dark Horse and others, lots of valuable advice. I would like to add this Tip & Trick: When all the impeller parts are in the system (mostly in the heat exchanger), you can get them out easily by backwashing. I did this by disconnecting the hose going from the heat exchanger to the exhaust elbow. And used the deck shower to backwash. The deck shower's head nicely fitted in the existing hose.
If you put a bucket below the raw water pump, with the cover off and the impeller out, the small impeller bits might be in the bucket instead of in the bilge. It is a wonderful sight to see them all in the bucket after such a small job.

With this trick you do not have to open the heat exchanger, this saves a lot of work.

I like it. Thanks.

[Sailor 99]

Originally Posted by Captain Graham

A diesel engine only needs electrical power when starting for the glow plugs (heater) and the starting motor.
So you really do not need an alternator at all to generate power, you just need a battery fully charged.

But you will still need an alternator that can spin so that the belt can power the water pump.
I do not now how often an alternator will lock up or freeze not allowing it to spin.

The issue with having a spare alternator and starting motor is will it be in good working order after being stored on your boat for 10 years.
I would recommend if you have these spares on board you should vacuum seal then keeping all moisture out.

Yes and all your tools need to be in a dry bag too. My buddy bought his dad's boat which was down south for years. Everything was pretty much a solid block of rust. Drill press, the heavy cutters for cutting away the rig. Everything.

[Cpt Mark]

[QUOTE=Dark Horse;2855580]

Originally Posted by Jef & Marin, Netherlands

I like it. Thanks.

This is a neat trick but preventative maintenance is better. Replace the impeller every 2 years or annually if you prefer. They are not much money and you will never have this problem. If you run aground in soft sand/mud and run the engine to get you out, replace the impeller as soon as practible.

[Sailor 99]

Originally Posted by Tetepare

LOL. I bought a backup starter 15 years ago as insurance against starter failure. It's paid off remarkably, I'm still running the 29 year old starter and the backup sits and collects dust.


I should have bought a spare fuel tank back then for the same reason.

Yup that is what we want to happen. I want an alternator, a start and even a water pump for my engine. All of these things in a car I would not even consider getting a spare for. If the engine water pump ( not raw water pump) goes on your boat it is going to go at the worst possible time and your not going to easily get a spare. FYI, its not the pump itself that dies, it is the bearing. When its done, its done.



I took the alternator in from my Beta Marine 75 to get it converted to external regulation. It has 271 hrs on it. Bearings where already making noise so the guy showed me and asked me if I wanted it fixed. He showed me another alternator that was good to compare with.


Yup fix it.

[Sailor 99]

Originally Posted by Dark Horse

It helps to be mechanically inclined but videos on how to do this stuff are all over youtube.



A lot of it is common sense. Get in there and work on them and it becomes clear pretty fast. I always had an issue with diesel engines could not wrap my head around them till I took the fuel system apart on one for repair. Easy peasey... Would rather work on them than anything else now.

But you also need the tools to fix all of this stuff.

Forgot, you also need a torque wrench.

[Sailor 99]

Originally Posted by charliehows

best tool in your toolbox is a thorough knowledge of, and confidence in the sailing capabilities of your boat, know what you can and, more importantly, can't do under sail.
Dont get me wrong, I love my little diesel donkey but it does like to have its bit of a joke on me, particularly when in a bit of a critical situation.

Very true. If you have never sailed your boat into its slip, this year might be a good year to try it.



The first day out with my first boat we blew the exhaust system and that was all she wrote.... Sailed into that slip and never even put a mark on her.

[Sailor 99]

One other thing for those not so mechanically inclined. Get mechanically inclined. I live in Toronto, Ontario. Toronto proper is the 4th largest city in North America. When you take in the entire GTA, its almost as large as New York City.


You can not find a diesel mechanic that will work on your boat here for love nor money. The few there are are working 50 to 60 hrs a week all spring summer and fall.



If you can't find one in the 4th largest city in North America what do you think your chances are out in the tropical islands of the world.


I am not saying you should be able to do a complete rebuild on your engine but you should be able to read a service manual and be able to re and re the engine head. Its not that difficult and a service manual tells you everything you need to know.

[fish53]

"should"? You should be able to do all that is mechanically relevant, there are two alternatives however, don't have anything mechanical or have a healthy bank account.

[arcticmonkey]

kudos... all.... liked the "spare starter" one... hauling out once a year involves checking through hulls... take the hoses off the through hulls grease and replace if any corrosion visable clamps yada yada... ounce of prevention... pound of cure... thanks gramma