Engine woes on CD27
Moderator: Jim Walsh
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Tom in Cambria
- Posts: 120
- Joined: Jan 29th, '06, 22:39
- Location: Cape Dory 31
Raw water cooled engine
Al has it right and the reason it makes a difference is that if you've been running salt water through the engine for 20+ years, the chances are that it has eaten away most of the metal parts and the engine probably isn't worth saving. On the other hand if the saltwater has only been going through the heat exchanger and it's fresh water with coolant that's been circulating through the engine, the chances are there is no damage to the metal parts of the engine from saltwater and it's pretty much good as new except for the worn parts. In either case saltwater comes through a throughull and a hose runs from there up to a pump on the engine. In a raw water cooled engine the pump pushes the saltwater through the engine, but in a coolant cooled engine the pump pushes the salt water through a "heat exchanger" and the saltwater never touches the actual engine. The heat exchanger is an often cylindrical shaped device in which the hot coolant from the engine runs through a metal tube inside a tank that is filled with cold seawater, so that the heat from the coolant is transferred or "exchanged" into the cold seawater. The seawater has to be cooled or it would heat up and stop cooling the hot coolant and that's why you need a pump to bring the cold sea water from the throughull and push it through the tank and out your exhaust pipe. Hence the term "wet exhaust". If you don't have a raw-water cooled engine, then somewhere you will have a tank in which you add coolant like you do to the radiator on your car. Sounds complicated, but it actually isn't as complicated as it sounds in words.
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Oswego John
- Posts: 3535
- Joined: Feb 5th, '05, 20:42
- Location: '66 Typhoon "Grace", Hull # 42, Schooner "Ontario", CD 85D Hull #1
Things Might Not Be So Bad
Cliff,
There is a remote chance that you might luck out with your "dead" engine.
You say that water entered your engine. One thing about water is that it doesn"t compress. If your engine is running and water enters the combustion chamber, somethings gotta give.
Several things could have happened for loss of compression. The engine could have a blown head gasket, a broken compression ring(s), a burnt valve lip or valve seat. A long shot is maybe the engine somehow jumped time or has a bent valve stem.
There are more serious things that could be wrong, but keep your fingers crossed. The trouble might be far less serious than the scenario crossing your mind might be. Maybe, maybe not.
If tests work out in your favor, you might not have to yank the engine after all. Remember, keep the fingers crossed. Knocking on wood really helps a lot.
Good luck,
O J
There is a remote chance that you might luck out with your "dead" engine.
You say that water entered your engine. One thing about water is that it doesn"t compress. If your engine is running and water enters the combustion chamber, somethings gotta give.
Several things could have happened for loss of compression. The engine could have a blown head gasket, a broken compression ring(s), a burnt valve lip or valve seat. A long shot is maybe the engine somehow jumped time or has a bent valve stem.
There are more serious things that could be wrong, but keep your fingers crossed. The trouble might be far less serious than the scenario crossing your mind might be. Maybe, maybe not.
If tests work out in your favor, you might not have to yank the engine after all. Remember, keep the fingers crossed. Knocking on wood really helps a lot.
Good luck,
O J
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Carter Brey
- Posts: 709
- Joined: Feb 5th, '05, 12:02
- Location: 1982 Sabre 28 Mk II #532 "Delphine"
City Island, New York - Contact:
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Maine Sail
- Posts: 839
- Joined: Feb 8th, '06, 18:30
- Location: Canadian Sailcraft 36T
Cliff..
Have you tried contacting Hansen Marine? They are the North East distributor for Westerbeke and I know they have a full machine shop and last I knew still did re-builds. If you can get the engine out you can bring it in the car it anywhere you'd like an are not beholden to one repair facility. that engine should fit easily in the back of a pick up truck..
John Payne is the service manager at Hansen and a very nice guy: hansen@hansenmarine.com or 781-639-7138 ext. 138
John Payne is the service manager at Hansen and a very nice guy: hansen@hansenmarine.com or 781-639-7138 ext. 138
motor
The PO of my boat repowered with a Yanmar and added new shaft, exhaust, dripless seal, seacock, etc. He spent well over $8000 on the project and did not recoup any of that when he sold to me, with 100 hours on it. It is VERY nice having a new motor, but I didn't have to pay for it. If you really think you'll sail that boat for a good bit longer and have the money, I'd consider it and add extra $ to cover unknowns.
Otherwise I'd use the resources all these guys have listed and really think about rebuild.
Not sure this is helpful and probably redundant, but wanted to emphasize the reality that you'll not get your money out of a repower if you sell anytime soon. sound like a full diagnosis is in order. OJ may be right, it may not be as bad as it seems.
Knocking on wood in North Cackalacky,
Chase
Otherwise I'd use the resources all these guys have listed and really think about rebuild.
Not sure this is helpful and probably redundant, but wanted to emphasize the reality that you'll not get your money out of a repower if you sell anytime soon. sound like a full diagnosis is in order. OJ may be right, it may not be as bad as it seems.
Knocking on wood in North Cackalacky,
Chase
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Matt Cawthorne
- Posts: 355
- Joined: Mar 2nd, '05, 17:33
- Location: CD 36, 1982
Hull # 79
I smell a rat.
It would be a rare diesel, indeed, that generates 450 psi on a compression test. You should check the specifications yourself before you go and dump a pile of money on the engine.
Raw water cooled diesels can be cleaned out. My brother was having overheating problems on the volvo engine in his Sabre 28 and had a good mechanic run some sort of process on it that cleaned all of the build-up out of the cooling passages. The overheating problem went away. I think that the work was done at Vosbury's in the Annapolis area, but there have to be shops much closer to you that can do the same job.
Matt
Raw water cooled diesels can be cleaned out. My brother was having overheating problems on the volvo engine in his Sabre 28 and had a good mechanic run some sort of process on it that cleaned all of the build-up out of the cooling passages. The overheating problem went away. I think that the work was done at Vosbury's in the Annapolis area, but there have to be shops much closer to you that can do the same job.
Matt
Compression - and a couple of questions
The westerbeke service manual gives the following;
Compression pressure @280 RPM Standard value - 455 PSI...
Repair Limit - 370 PSI...Service Limit 312 PSI
What is meant by repair limit vs service limit?
Compression pressure difference between cylinders (maximum) 35.6 PSI
My Westerbeke 13 A is the original (1984). I believe, I have replaced the exhaust elbow twice (believe cost for part was about $80) I am a far way from being a mechanic, but I have always (knocking on wood) been able to fiqure out why the engine would not start.
I am curious what the bill for "several thousand dollars"was for?
Compression pressure @280 RPM Standard value - 455 PSI...
Repair Limit - 370 PSI...Service Limit 312 PSI
What is meant by repair limit vs service limit?
Compression pressure difference between cylinders (maximum) 35.6 PSI
My Westerbeke 13 A is the original (1984). I believe, I have replaced the exhaust elbow twice (believe cost for part was about $80) I am a far way from being a mechanic, but I have always (knocking on wood) been able to fiqure out why the engine would not start.
I am curious what the bill for "several thousand dollars"was for?
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Carter Brey
- Posts: 709
- Joined: Feb 5th, '05, 12:02
- Location: 1982 Sabre 28 Mk II #532 "Delphine"
City Island, New York - Contact:
Re: Compression - and a couple of questions
Marilou is correct. My Westerbeke service manual uses slightly different terminology, which may clarify things somewhat. Here are the values for the W13:marilou wrote:The westerbeke service manual gives the following;
Compression pressure @280 RPM Standard value - 455 PSI...
Repair Limit - 370 PSI...Service Limit 312 PSI
What is meant by repair limit vs service limit?
Compression pressure difference between cylinders (maximum) 35.6 PSI
My Westerbeke 13 A is the original (1984). I believe, I have replaced the exhaust elbow twice (believe cost for part was about $80) I am a far way from being a mechanic, but I have always (knocking on wood) been able to fiqure out why the engine would not start.
I am curious what the bill for "several thousand dollars"was for?
Standard: 455 psi at 280 rpm.
Minimum (or lowest acceptable normal value): 370 psi at 280 rpm.
Overhaul (self-explanatory): 312 psi at 280 rpm.
Best regards,
Carter Brey
Sabre 28 Mk II #532 "Delphine"
City Island, NY
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Kurt
- Posts: 188
- Joined: Feb 8th, '05, 11:12
- Location: 27' Cape Dory (Alerion),
9' Dyer,
Grosse Pointe, Michigan
Diesel engine fuel injection pumps....NOT SIMPLE TO REPAIR
A couple of the respondents to this thread have talked about the simplicity of a small diesel engines and the ease with which these engines can be rebuilt. But what about the fuel injection pump and injectors? These highly precise mechanical devices are built to incredibly close tolerances and then seem to run forever...but what if they break? Does anyone on the board know anything about repairing/adjusting a diesel engine fuel injection pump?
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Chris Reinke
- Posts: 179
- Joined: Apr 14th, '05, 14:59
- Location: CD330 - Innisfail (Gaelic for "A Little Bit Of Heaven on Earth"), Onset, MA
Kurt - I have never heard of anyone repairing a fuel pump. Given the closed construction I am not even sure if the pump can be "adjusted". I was unable to get my M30 above idle due to lack of fuel pressure.
I did replace my westerbeke pump while on a trip last summer. I placed a call to John Payne at Hansen (someone above also mentioned John as a good resource) and he advised me that all pumps are pretty much the same. I needed one that would produce 4-7psi, which I was able to get at a local auto-supply store for about $45. I did purchase a replacement Westerbeke pump which I now keep onboard, but the auto part one is working fine.
I did replace my westerbeke pump while on a trip last summer. I placed a call to John Payne at Hansen (someone above also mentioned John as a good resource) and he advised me that all pumps are pretty much the same. I needed one that would produce 4-7psi, which I was able to get at a local auto-supply store for about $45. I did purchase a replacement Westerbeke pump which I now keep onboard, but the auto part one is working fine.
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Kurt
- Posts: 188
- Joined: Feb 8th, '05, 11:12
- Location: 27' Cape Dory (Alerion),
9' Dyer,
Grosse Pointe, Michigan
fuel injection pump versus fuel life pump
Chris,
It sounds like you replaced the diaphram operated fuel lift pump...not the high pressure fuel injection pump. A typical high pressure fuel pump would cost in the hundreds, perhaps thousands of dollars and is a very complicated and very precision machine.
Kurt
It sounds like you replaced the diaphram operated fuel lift pump...not the high pressure fuel injection pump. A typical high pressure fuel pump would cost in the hundreds, perhaps thousands of dollars and is a very complicated and very precision machine.
Kurt
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David Perry
- Posts: 32
- Joined: Apr 11th, '06, 10:32
Westerbeke 13
Cliff, I hope you can consider having your engine re-built. It is fresh water cooled, and is newer than the boat, as her second owner installed it in 1988, replacing a Yanmar 7 hp. Taking it to Hansen Marine, the Westerbeke distributor in Marblehead, MA, is an excellent choice for a company to re-build the engine, as suggested. Removing the engine and transmission yourself may be a good option. You should be able to unbolt the coupling as you just had the shaft and cutlass bearing replaced. Then just put it in the car and drive it down there. Have it professionally re-installed if it gives you more confidence.
Think of all of the new parts you just bought, too, for this engine, which would not likely work on a different engine installation.
Think of all of the new parts you just bought, too, for this engine, which would not likely work on a different engine installation.
Rebuild
Thanks again, everyone. It's in indoor storage this season for the first time -- and the mechanic tells me that I am not allowed to remove it myself while it is inside. No work from customers because of insurance. So this will have to wait until Spring when I can hoist it out myself. Hansen, curiously, is the one telling the mechanic that I'm better off not trying to rebuild it, that parts won't be available, and so on. I'm planning on calling them directly tomorrow to see if what I hear is the same as what my yard is telling me.
Cliff Guthrie
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Andy Denmark
- Posts: 630
- Joined: Feb 5th, '05, 11:38
Rebuilding vs. new
I am also contemplating either a rebuild or a new powerplant. The three engines I've considered are the Beta, Yanmar, and another Westerbeke. But further analysis, when considering all the other stuff you have to do with a different engine -- exhaust, linkage, mounts, shaft coupling, control panel, etc. -- all add up to significant costs, either of your own time or boatyard time, not to mention a huge hassle and/or discomfort factor. The "drop it in and hook it back up" approach seems much less daunting.
I'm awaiting an estimate from Atlantic Yacht Basin, a Westerbeke distributor like Hansen, to get a total bottom-up rebuild. They say there's no difficulty with parts availability and will supply a limited warranty on the job. My main issue is the rear seal but as long as the engine is torn down that far I'd like a thorough inspection and replacement of anything that looks questionable. I might even contemplate taking the engine to Hansen in Marblehead if that seems a better deal and visit Robinhood and friends in Camden on the trip.
Since this boat is ultimately going out to the Seattle area I'd like it to be a near "right" as it can be made while she's here with me to deal with it.
You might add up the costs of these peripheral parts of the repowering job and see how that affects your net cost. In my case, the savings are a big percentage of the total. Certainly cheaper than a new installation and a known quantity to boot.
FWIW
________
IOLITE VAPORIZER REVIEW
I'm awaiting an estimate from Atlantic Yacht Basin, a Westerbeke distributor like Hansen, to get a total bottom-up rebuild. They say there's no difficulty with parts availability and will supply a limited warranty on the job. My main issue is the rear seal but as long as the engine is torn down that far I'd like a thorough inspection and replacement of anything that looks questionable. I might even contemplate taking the engine to Hansen in Marblehead if that seems a better deal and visit Robinhood and friends in Camden on the trip.
Since this boat is ultimately going out to the Seattle area I'd like it to be a near "right" as it can be made while she's here with me to deal with it.
You might add up the costs of these peripheral parts of the repowering job and see how that affects your net cost. In my case, the savings are a big percentage of the total. Certainly cheaper than a new installation and a known quantity to boot.
FWIW
________
IOLITE VAPORIZER REVIEW
Last edited by Andy Denmark on Mar 16th, '11, 07:05, edited 1 time in total.
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Oswego John
- Posts: 3535
- Joined: Feb 5th, '05, 20:42
- Location: '66 Typhoon "Grace", Hull # 42, Schooner "Ontario", CD 85D Hull #1
DEAD ENGINE ?
Cliff,
The question of "What do you mean by your motor is dead and wants to be replaced" begs for an answer. A several thousand dollar answer at that. At this point in time, I have to agree with Perry, Andy and all the other earlier replys thinking that you should rebuild. I'm not about to argue with the experts but I can't imagine that parts aren't available for a rebuild.
I can't help but feel that you should get a second opinion from one or two known competent Diesel mechanics as to what the status of your engine is before you make any decisions on the next step. Again, I repeat myself, the trouble may or may not be as serious as was first thought to be.
I'm going to give my slant on a few recent posts.
*****************************************************
Posted: Mon 1/7/08 9:49 am Post subject: Re: Compression - and a couple of questions
--------------------------------------------------------------------------------
marilou wrote:
The westerbeke service manual gives the following;
Compression pressure @280 RPM Standard value - 455 PSI...
Repair Limit - 370 PSI...Service Limit 312 PSI
What is meant by repair limit vs service limit?
Compression pressure difference between cylinders (maximum) 35.6 PSI
My Westerbeke 13 A is the original (1984). I believe, I have replaced the exhaust elbow twice (believe cost for part was about $80) I am a far way from being a mechanic, but I have always (knocking on wood) been able to fiqure out why the engine would not start.
I am curious what the bill for "several thousand dollars"was for?
[quote Carter]
Marilou is correct. My Westerbeke service manual uses slightly different terminology, which may clarify things somewhat. Here are the values for the W13:
Standard: 455 psi at 280 rpm.
Minimum (or lowest acceptable normal value): 370 psi at 280 rpm.
Overhaul (self-explanatory): 312 psi at 280 rpm.
Best regards,
Carter Brey
Sabre 28 Mk II #532 "Delphine"
City Island, NY
*****************************************************
Compression difference between cylinders should be no more than 35.6 psi on engines with two or more cylinders. All cylinders should have about the same wear and tear on them due to proper use. As time passes, it is normal for some loss in compression equally in all cylinders. When compression in one cylinder is greater than 35.6 psi than that in another cylinder, it signals trouble in the lower cylinder and should be checked out.
With a fully charged starting battery, an engine with good compression of about 455psi should rotate at about 280 rpms while starting. As most of you already know, a Diesel engine has no electrical spark to initiate ignition. Due to the high compression of the air to over 600 psi at the top of the intake stroke, tremendous heat builds up and ignites the fuel charge. Due to normal wear and tear, in time the compressions lowers.
When the compression falls to a minimum acceptable pressure of 370 psi @ 280 rpms. Starting will be harder and without glow plugs, difficult to start in colder weather. As compression lowers, so does combustion chamber temperature, necessary for ignition.
When the compression lowers to 312 psi, rebuild is necessary as too little heat is generated by compression to ignite the fuel charge. You will note that as compression falls off, all other conditions being equal, the starting rpms will be much higher than 280 rpms.
*****************************************************
[Quote Kurt]
Boat: 27' Cape Dory (Alerion), 9' Dyer, Grosse Pointe, Michigan
Posted: Tue 1/8/08 7:24 pm Post subject: Diesel engine fuel injection pumps....NOT SIMPLE TO REPAIR
--------------------------------------------------------------------------------
A couple of the respondents to this thread have talked about the simplicity of a small diesel engines and the ease with which these engines can be rebuilt. But what about the fuel injection pump and injectors? These highly precise mechanical devices are built to incredibly close tolerances and then seem to run forever...but what if they break? Does anyone on the board know anything about repairing/adjusting a diesel engine fuel injection pump?
*****************************************************
[Quote Chris Reinke]
Boat: CD330 - Innisfail (Gaelic for "A Little Bit Of Heaven on Earth"), Onset, MA
Posted: Tue 1/8/08 7:34 pm Post subject:
--------------------------------------------------------------------------------
Kurt - I have never heard of anyone repairing a fuel pump. Given the closed construction I am not even sure if the pump can be "adjusted". I was unable to get my M30 above idle due to lack of fuel pressure.
I did replace my westerbeke pump while on a trip last summer. I placed a call to John Payne at Hansen (someone above also mentioned John as a good resource) and he advised me that all pumps are pretty much the same. I needed one that would produce 4-7psi, which I was able to get at a local auto-supply store for about $45. I did purchase a replacement Westerbeke pump which I now keep onboard, but the auto part one is working fine.
*****************************************************
Most Diesel engines that I am familiar with have two fuel pumps. One is a low pressure, high volume, diaphragm pump that delivers fuel from the fuel tank to the engine. They deliver fuel at from 4 to8 psi, depending on the engine make and model. Any surplus, unused fuel is returned to the tank via a separate bypass fuel line.
The other pump is a high pressure, low volume, usually a piston pump, that raises the fuel pressure so that it can be injected as an atomized spray, into each cylinder's injection valve or port.
These high pressure (hp) pumps are very rugged and seldom break down. They do cause trouble from rare time to time. The hp pump is rather complicated. It is also an extremely precise instrument that times the injection to each cylinder, but also meters the portion of fuel to be delivered, depending on the throttle setting.
It is hard to imagine having an injection of just the proper amount fuel delivered to each cylinder at approximately 10° btdc (before top dead center). Now in your head imagine that this is multiplied by the number of cylinders rotating at, say, 3,000 rpms. And this feat is repeated for hours, days at a time. If the timing is off by a degree or so, you get preignition and severe engine knock. A retarded fuel supply results in incomplete combustion, black, sooty smoke and air pollution, as well as carbon buildup in the exhaust system.
It is for the reasons stated above that very few boat owners have any experience with fuel injection. These pumps are so precise in their calibrations that there is very little to no adjustments that a lay person with no experience could hope to adjust one. The rare time that one of these hp pumps needs attention, it is far wiser to have a specialist repair or recalibrate it, using the special equipment necessary to repair it properly.
I know that this post is long but there is one more thing that must be mentioned.
Use extreme caution when working around anything to do with fuel injection. Just because the engine isn't running doesn't mean that the system isn't charged with high pressure fuel. If you don't know what you are doing, I advise you not to tinker with it.The pressure can be very high, in some instances over 2,000 bars. One bar is a little higher than 14.5 psi. The newer models with electronic modules and rail distribution can achieve 29,000 bars pressure. Stay away.Some unwary mechanics have suffered from hypodermic fuel injection through their pores and blindness.
O J
The question of "What do you mean by your motor is dead and wants to be replaced" begs for an answer. A several thousand dollar answer at that. At this point in time, I have to agree with Perry, Andy and all the other earlier replys thinking that you should rebuild. I'm not about to argue with the experts but I can't imagine that parts aren't available for a rebuild.
I can't help but feel that you should get a second opinion from one or two known competent Diesel mechanics as to what the status of your engine is before you make any decisions on the next step. Again, I repeat myself, the trouble may or may not be as serious as was first thought to be.
I'm going to give my slant on a few recent posts.
*****************************************************
Posted: Mon 1/7/08 9:49 am Post subject: Re: Compression - and a couple of questions
--------------------------------------------------------------------------------
marilou wrote:
The westerbeke service manual gives the following;
Compression pressure @280 RPM Standard value - 455 PSI...
Repair Limit - 370 PSI...Service Limit 312 PSI
What is meant by repair limit vs service limit?
Compression pressure difference between cylinders (maximum) 35.6 PSI
My Westerbeke 13 A is the original (1984). I believe, I have replaced the exhaust elbow twice (believe cost for part was about $80) I am a far way from being a mechanic, but I have always (knocking on wood) been able to fiqure out why the engine would not start.
I am curious what the bill for "several thousand dollars"was for?
[quote Carter]
Marilou is correct. My Westerbeke service manual uses slightly different terminology, which may clarify things somewhat. Here are the values for the W13:
Standard: 455 psi at 280 rpm.
Minimum (or lowest acceptable normal value): 370 psi at 280 rpm.
Overhaul (self-explanatory): 312 psi at 280 rpm.
Best regards,
Carter Brey
Sabre 28 Mk II #532 "Delphine"
City Island, NY
*****************************************************
Compression difference between cylinders should be no more than 35.6 psi on engines with two or more cylinders. All cylinders should have about the same wear and tear on them due to proper use. As time passes, it is normal for some loss in compression equally in all cylinders. When compression in one cylinder is greater than 35.6 psi than that in another cylinder, it signals trouble in the lower cylinder and should be checked out.
With a fully charged starting battery, an engine with good compression of about 455psi should rotate at about 280 rpms while starting. As most of you already know, a Diesel engine has no electrical spark to initiate ignition. Due to the high compression of the air to over 600 psi at the top of the intake stroke, tremendous heat builds up and ignites the fuel charge. Due to normal wear and tear, in time the compressions lowers.
When the compression falls to a minimum acceptable pressure of 370 psi @ 280 rpms. Starting will be harder and without glow plugs, difficult to start in colder weather. As compression lowers, so does combustion chamber temperature, necessary for ignition.
When the compression lowers to 312 psi, rebuild is necessary as too little heat is generated by compression to ignite the fuel charge. You will note that as compression falls off, all other conditions being equal, the starting rpms will be much higher than 280 rpms.
*****************************************************
[Quote Kurt]
Boat: 27' Cape Dory (Alerion), 9' Dyer, Grosse Pointe, Michigan
Posted: Tue 1/8/08 7:24 pm Post subject: Diesel engine fuel injection pumps....NOT SIMPLE TO REPAIR
--------------------------------------------------------------------------------
A couple of the respondents to this thread have talked about the simplicity of a small diesel engines and the ease with which these engines can be rebuilt. But what about the fuel injection pump and injectors? These highly precise mechanical devices are built to incredibly close tolerances and then seem to run forever...but what if they break? Does anyone on the board know anything about repairing/adjusting a diesel engine fuel injection pump?
*****************************************************
[Quote Chris Reinke]
Boat: CD330 - Innisfail (Gaelic for "A Little Bit Of Heaven on Earth"), Onset, MA
Posted: Tue 1/8/08 7:34 pm Post subject:
--------------------------------------------------------------------------------
Kurt - I have never heard of anyone repairing a fuel pump. Given the closed construction I am not even sure if the pump can be "adjusted". I was unable to get my M30 above idle due to lack of fuel pressure.
I did replace my westerbeke pump while on a trip last summer. I placed a call to John Payne at Hansen (someone above also mentioned John as a good resource) and he advised me that all pumps are pretty much the same. I needed one that would produce 4-7psi, which I was able to get at a local auto-supply store for about $45. I did purchase a replacement Westerbeke pump which I now keep onboard, but the auto part one is working fine.
*****************************************************
Most Diesel engines that I am familiar with have two fuel pumps. One is a low pressure, high volume, diaphragm pump that delivers fuel from the fuel tank to the engine. They deliver fuel at from 4 to8 psi, depending on the engine make and model. Any surplus, unused fuel is returned to the tank via a separate bypass fuel line.
The other pump is a high pressure, low volume, usually a piston pump, that raises the fuel pressure so that it can be injected as an atomized spray, into each cylinder's injection valve or port.
These high pressure (hp) pumps are very rugged and seldom break down. They do cause trouble from rare time to time. The hp pump is rather complicated. It is also an extremely precise instrument that times the injection to each cylinder, but also meters the portion of fuel to be delivered, depending on the throttle setting.
It is hard to imagine having an injection of just the proper amount fuel delivered to each cylinder at approximately 10° btdc (before top dead center). Now in your head imagine that this is multiplied by the number of cylinders rotating at, say, 3,000 rpms. And this feat is repeated for hours, days at a time. If the timing is off by a degree or so, you get preignition and severe engine knock. A retarded fuel supply results in incomplete combustion, black, sooty smoke and air pollution, as well as carbon buildup in the exhaust system.
It is for the reasons stated above that very few boat owners have any experience with fuel injection. These pumps are so precise in their calibrations that there is very little to no adjustments that a lay person with no experience could hope to adjust one. The rare time that one of these hp pumps needs attention, it is far wiser to have a specialist repair or recalibrate it, using the special equipment necessary to repair it properly.
I know that this post is long but there is one more thing that must be mentioned.
Use extreme caution when working around anything to do with fuel injection. Just because the engine isn't running doesn't mean that the system isn't charged with high pressure fuel. If you don't know what you are doing, I advise you not to tinker with it.The pressure can be very high, in some instances over 2,000 bars. One bar is a little higher than 14.5 psi. The newer models with electronic modules and rail distribution can achieve 29,000 bars pressure. Stay away.Some unwary mechanics have suffered from hypodermic fuel injection through their pores and blindness.
O J