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Old 03-22-2013, 09:33 PM   #141
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My take on the Dino vs synth is... It can be discussed for ever cause there are way too many variables in engine design , year , model, load , rpm , usage, condition etc from all the different posters who offer a contribution to this issue, You cant compare a newer common rail electronic fuel management Diesel with 2 oil pumps, high pressure piston jets, large oil coolers, multi oil by pas systems and a centrifuge to a older low tech good ole trust worthy ford 120 found in so many trawlers, Perkins 6.354s also, If you own a new design engine then synth has value but in my opinion if ya got a old school ford or Perkins its far better to change out Dino more often like every 100 hrs max with a filter change every 50hrs, The cost is not that more than purchasing synth and trying to go for 200hrs between services may not pan out, I think you all should save your bucks on synth oil and apply the savings to clean fuel cause that's what causes all the carbon problems to begin with, but that's just my opinion
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Old 03-22-2013, 09:47 PM   #142
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My take on the Dino vs synth is... It can be discussed for ever cause there are way too many variables in engine design , year , model, load , rpm , usage, condition etc from all the different posters who offer a contribution to this issue, You cant compare a newer common rail electronic fuel management Diesel with 2 oil pumps, high pressure piston jets, large oil coolers, multi oil by pas systems and a centrifuge to a older low tech good ole trust worthy ford 120 found in so many trawlers, Perkins 6.354s also, If you own a new design engine then synth has value but in my opinion if ya got a old school ford or Perkins its far better to change out Dino more often like every 100 hrs max with a filter change every 50hrs, The cost is not that more than purchasing synth and trying to go for 200hrs between services my not pan out, I think you all should save your bucks on synth oil and apply the savings to clean fuel cause that's what causes all the carbon problems to begin with, but that's just my opinion
Why wait till 50 hours on the filter...how about 25 and 50 on the oil change?
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Old 03-22-2013, 09:57 PM   #143
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Craig why would you change the filter more often than the oil?

I usually do the opposite. I change the oil 3 times and the filter once. The boat engine operates in such a clean environment I reason that the filter would take a long time to fill up w contaminants so I leave it alone over half of the time.

What's your reason for changing the filter more often?
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Old 03-22-2013, 10:00 PM   #144
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Oil filters are cheep but if you need 25hr change outs you may consider a leak down test or save the money for rings, liners and injector tips. The one bad thing about old design Diesels is you never know when a oil filter goes into bypass, Carbon has very much a snow ball effect, It starts off small but very quickly gets large, often the older Diesels found in small trawlers do not have to work very hard to move the boat from a to b so they seem to last forever, just not very efficiently.
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Old 03-22-2013, 10:11 PM   #145
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Craig why would you change the filter more often than the oil?

I usually do the opposite. I change the oil 3 times and the filter once. The boat engine operates in such a clean environment I reason that the filter would take a long time to fill up w contaminants so I leave it alone over half of the time.

What's your reason for changing the filter more often?

On older Diesels that black out the oil fast, the carbon and soot can put the oil filter into by pass, especially when the engine oil is cold, the black oil is abrasive, oil filters are cheep insurance with the exception of Fram oil filters, they tend to blow the cardboard end caps and allow large amounts of trash thru the engine causing rod bearing failure.
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Old 03-22-2013, 10:20 PM   #146
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that's bs! you can use syn in old engines. I have a vintage ford tractor which I switched to sny in 2003 when I bought her and since then I even drove it for a bit with no oil in the crankcase by accident. I had just changed the oil and my neighbor came over to ask a question 2006. I then went to work in the pasture until I noticed a red light on the dash. I thought, crap, I didn't put enough oil in so drove back to the farm a half mile away then added oil to have it run out on the ground. I had forgotten to tighten the drain plug and it had fallen out. I figured it was time for a rebuild but I decided to fill the crank case and see if she would run. She ran fine, and still runs fine, no smoke, same power. After this I now believe what I read about syn oil bonding to the metal so that cold starts do not cause the wear that they do with conventional oils.
I was a mobil 1 junky for years but now use amsoil. amsoil makes a marine diesel oil that should work great in your lehman AMSOIL SAE 15W-40 Heavy-Duty Diesel and Marine Motor Oil
I use this in my 1975 ford 2000 tractor
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Old 03-22-2013, 10:33 PM   #147
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Craig why would you change the filter more often than the oil?

I usually do the opposite. I change the oil 3 times and the filter once. The boat engine operates in such a clean environment I reason that the filter would take a long time to fill up w contaminants so I leave it alone over half of the time.

What's your reason for changing the filter more often?
.
first of all syn oil doesn't form sludge like conventional oils do so there is no need to change the filter as often. syn also holds more sludge and dirt in suspension than conventional oils do giving your engine better protection. When I was servicing boats I found that most people didn't change the oil as often as they should making syn the logical choice.
Why not change the filter when you change the oil filters are cheap? I recommend extended oil change intervals with syn with filter change.
I recommend the manufacturers light duty oil change intervals with syn instead of the severe duty change interval. This way the cost of syn is hardly more than the cost of more frequent conventional oil changes. And this goes for boats cars tractors etc.
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Old 03-22-2013, 10:41 PM   #148
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A diesel engine is a fairly difficult lubrication application, mainly because of the fuel and soot loading. Good oils will use TAN boosters to alleviate the acidity of the partially burnt acidic fuel, dispersants and detergents for soot control, and antioxidants for high temperature and longevity. The base oil is nearly irrelevant for the application. Use a great quality petroleum base oil with a high VI and change your oil and filter often.

PS: I like synthetics, just not for this application.

PPS: The synthetic oil used in aero-derivative gas turbines is typically an organic ester due to high contact temperatures. Completely different animal. Frame gas turbines and steam turbines often run regular hydro cracked petroleum base oil.
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Old 03-22-2013, 11:11 PM   #149
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that's bs! you can use syn in old engines. I have a vintage ford tractor which I switched to sny in 2003 when I bought her and since then I even drove it for a bit with no oil in the crankcase by accident. I had just changed the oil and my neighbor came over to ask a question 2006. I then went to work in the pasture until I noticed a red light on the dash. I thought, crap, I didn't put enough oil in so drove back to the farm a half mile away then added oil to have it run out on the ground. I had forgotten to tighten the drain plug and it had fallen out. I figured it was time for a rebuild but I decided to fill the crank case and see if she would run. She ran fine, and still runs fine, no smoke, same power. After this I now believe what I read about syn oil bonding to the metal so that cold starts do not cause the wear that they do with conventional oils.
I was a mobil 1 junky for years but now use amsoil. amsoil makes a marine diesel oil that should work great in your lehman AMSOIL SAE 15W-40 Heavy-Duty Diesel and Marine Motor Oil
I use this in my 1975 ford 2000 tractor


I rebuilt the diesels in my 1971 ford 2000 diesel tractor some 15 years ago and the diesel in my ford 3000 4x4 diesel tractor shortly after, they both had over 10k on the clocks and ran fine, they only used dino oil and were way out of spec on the rod bearings to the point the crank pins were turning blue but they ran fine, But I have never ran them out of oil , could it be that ford just makes good diesel tractor engines ? I never said you could not or should not run synth oil in your old diesel, but synth oil will not help blow by in fact a lighter weight synth oil may make it worse over a heavier weight dino oil.
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Old 03-23-2013, 12:42 AM   #150
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Capthead - I read entire atricle. Thank you for the link!

No doubt that syn oil has many great features. I am thinking carefully about changing one of my classic or newer engines to syn oil... and then watch its performance closely. I need to read more info and it needs to be more recent reports that the 1970's one in Popular Science. My eyes and ears are wide open. Lubricant cost is too small a % of overall costs to be an item when it comes to extending engine life.

I'm on a serious search now to find out more about syn oil... before I actually try it out. Currently there is a 75% + chance that I will eventually try syn oil. Before this thread the chance was 10% -... Quite a turn in position!
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Old 03-23-2013, 07:59 AM   #151
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For me, the discussion ends there. While I'm sure the debate will continue, as far as I'm concerned, and for the engines we run (FL120s), Art's statement is the only one that bears remembering and adhering to.

Bob Smith told me a number of years ago that FL120s in service with the Washington State Ferry System ran in excess of 25,000 hours before needing a core overhaul. And that the same engine, operated, serviced, and maintained properly in recreational boat service is a 12,000 to 14,000 hour engine. In both cases, the engine earned this reputation on conventional oil if for no other reason than viable synthetics were not available back then.

I agree with Eric that while synthetics may have some advantages over conventional oils these advantages are in reality probably minimal to zip when it comes to the kinds of engines most of us run in our boats and the way we run them. Which means that using synthetics, while it may be technically advantageous in some tiny way, really makes no difference in reality other than to one's wallet.

A modern, high-reving, constantly-load-changing, close-tolerance engine in a vehicle is a different situation altogether. For the two new vehicles we own for which synthetic oil is specifically called for in the operators manual, we run the called-for synthetic and I would not put convernional oil in them for love nore money (although the Subaru manual states that conventional oils can be used "in an emergency and only for short periods" after which it must be replaced with the specified synthetic oil).

So while this thread seems to be a lively armchair discussion I think the only thing that's been said in it that's really worth heeding is Art's statement that I started this post with. That's my take on it all, anyway.
I could add, change filters more frequently. But I agree with that statement also.
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Old 03-23-2013, 11:02 AM   #152
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OMG Art's a convert. What kind of religion was that Art? ......... oh yea synthetic oil. Interesting old 1976 PM article. It's true. It's true. There's more religion in oil than anchors. And the most religious anchor man has turned up his nose completely on synthetic oil. Next generation anchors are the true religion and next generation oil is like the religions of the middle east. All kidding aside ...........................................

Cgaig S,
Never heard of filter "by pass". Must be when a filter gets so full of stuff it won't flow enough oil so a pressure relief valve "by passes" the oil. What else could it be? I think you're telling us that a filter can get plugged w normal operation. Very hard to believe Craig. But I'm open ..... not to propaganda like Art though. At least he says he's going to do some research. That link you posted is pure commercial propaganda and as such may not even be appropriate on this forum. But they let boat brokers post commercial links so why not you?
I really am open and have bought into some of the most extreme products available and will use synthetic oil if I think it's best. But I'll have to thumb my nose at a very large and well established body of engineers, engine manufacturers and commercial users that have little tendency to buy into anything that isn't 100% objective and well proven. The military is an objective group that gets into many very extreme conditions that prompts them to use synthetic oil and since they started the whole thing w syn oil that should be believable.
There are some car manufacturers that use and recommend syn oil but that is 100% for the high temp of turbos and otherwise car manufacturers are 100% w dino oil.

Personally I need to find out about filter capacity and expected accumulation rates in diesel engines first before I research synthetic oil and even then I doubt if I'll see a need great enough to warrant time spent doing research for something I'm 95% sure I'll not be needing. I'll wait and hear what Art uncovers in his new travels as a research engineer for Trawler Forum.
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Old 03-23-2013, 11:36 AM   #153
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OMG Art's a convert. What kind of religion was that Art? ......... oh yea synthetic oil.

I'll wait and hear what Art uncovers in his new travels as a research engineer for Trawler Forum.
GEEEEZZZ Eric - Talk bout being put on Da Spot! lol

Don't hold yer breath on my lube reports - I've been using HQ dino oil for decades, good additives too. And, although 75% ready to try syn oil... the last 25% could take years... may never reach 100%. I will however let cha know if I get more info worth a darn on dino - vs - syn... or God forbid, I take the plunge into syn at an early date! Would da big G consider that a sin! - LOL
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Old 03-23-2013, 11:39 AM   #154
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Some tricks for diesel boat owners, Cold starts are hard on engines that sit between start ups, Most engine ware comes from the lack of lubrication on bearings and cylinder thrust surfaces on cold starts, The cold oil viscosity will open the oil filter by pass valve allowing un filtered oil thru the system, Not good... The use of engine block heaters even in warm temps helps a lot, This allows for filtered oil on start up and reduces engine idle time which causes carbon build up + helps with condensation on machined surfaces, You can reduce the load on dry engine surfaces 10x by holding the engine fuel stop and crank the engine with out it starting for 20 seconds, This pre lubes the main and rods bearings and in some engines may provide some cylinder wall lube, This is a time tested procedure and will extend engine efficiency and life span with little to no cost and will work with dino or synth oils, Some synth oils may provide some protection from cold starts but i have not gone thru all the data and they sell engine pre lube kits that work but there is a cost involved. My thoughts are you should save your money and clean your fuel system cause that's where the carbon comes from and carbon eats engines.
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Old 03-23-2013, 11:58 AM   #155
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OMG Art's a convert. What kind of religion was that Art? ......... oh yea synthetic oil. Interesting old 1976 PM article. It's true. It's true. There's more religion in oil than anchors. And the most religious anchor man has turned up his nose completely on synthetic oil. Next generation anchors are the true religion and next generation oil is like the religions of the middle east. All kidding aside ...........................................

Cgaig S,
Never heard of filter "by pass". Must be when a filter gets so full of stuff it won't flow enough oil so a pressure relief valve "by passes" the oil. What else could it be? I think you're telling us that a filter can get plugged w normal operation. Very hard to believe Craig. But I'm open ..... not to propaganda like Art though. At least he says he's going to do some research. That link you posted is pure commercial propaganda and as such may not even be appropriate on this forum. But they let boat brokers post commercial links so why not you?
I really am open and have bought into some of the most extreme products available and will use synthetic oil if I think it's best. But I'll have to thumb my nose at a very large and well established body of engineers, engine manufacturers and commercial users that have little tendency to buy into anything that isn't 100% objective and well proven. The military is an objective group that gets into many very extreme conditions that prompts them to use synthetic oil and since they started the whole thing w syn oil that should be believable.
There are some car manufacturers that use and recommend syn oil but that is 100% for the high temp of turbos and otherwise car manufacturers are 100% w dino oil.

Personally I need to find out about filter capacity and expected accumulation rates in diesel engines first before I research synthetic oil and even then I doubt if I'll see a need great enough to warrant time spent doing research for something I'm 95% sure I'll not be needing. I'll wait and hear what Art uncovers in his new travels as a research engineer for Trawler Forum.


Eric, The oil filter by pass valve operates on a pressure differential or drop thru the filter, When the filter is clogged or the oil viscosity is high the valve opens allowing un filtered oil thru the engine, It is the lesser of too evils, dirty oil is better than no oil, oil filter capacity depends on size and media used. hope this helps.
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Old 03-23-2013, 12:01 PM   #156
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You can reduce the load on dry engine surfaces 10x by holding the engine fuel stop and crank the engine with out it starting for 20 seconds, This pre lubes the main and rods bearings and in some engines may provide some cylinder wall lube, This is a time tested procedure and will extend engine efficiency and life span with little to no cost and will work with dino or synth oils.
Craig - I could not agree more! Thanks for posting that manner of engine wear reduction. Hands-Down It Really Works!

There have been threads on TF - couple years ago before current forum owners - where I was basically called a nut that just wanted to ruin starters by using them too much for this type of bearing-pre-lube technique. What I can say is: I learned to do this from an expert marine mechanic in the late 1950's... as a kid on LI NY. And, I've replaced a few inexpensive starters in my time - BUT - I nearly never have had to replace or rebuild my engines after 100's K miles on the road or many 1000's hours of use on the water... because I use best lubes/filters, change lubes often... AND, before every start, pre lube internal surfaces by reaching oil pressure using starter only, before letting engine fire off and begin placing real loads on bearings etc!
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Old 03-23-2013, 12:06 PM   #157
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Maybe sunchaser could shed more light on it. He seems to have a heavy equipment background
My big fleet experience spans over 45 years with the largest engines up to 4000 HP. I've had legions of lubrication engineers and the best of diesel designers walk me through decades of dyno testing and real lubrication progress as oil life has been extended way beyond what diesels of the 60s were using, largely due to better lub systems, filters, oils and lower sulfur fuels. Warranty adherence is essential rendering synthetic way too costly to use. Unless of course the warranty hours between rebuilds is extended to pay for the extra tens of thousands of dollars for syn use per engine during a 2 to 3 year life at 24/7.

As of yet, few if any major diesel engine mfrs allow a longer period between oil changes when using syn vs dino due to logging (detailed software programs) oil analysis for loading of sulfates, acids, particulates, metals, C (soot), water etc. Oil filtering systems are designed to trap the big particles while letting the submicron pass, which is why our oil turns black due to very fine and harmless "carbon black."

As Marin, Art and most others seem to agree, my advice is to go by the book and change oil and filters per recommendations, remembering that syn does not necessarily extend the hours between changes. Of course if you shorten your life by 25% by using "extended life" (says who?) syn this means you will rebuild your Lehman at 12,000 rather than 16,000 hours - so use your synthetic and feel good!

BTW, my 2003 Perkins Sabres/Cat 3056 engines have a 400 hour by the book oil change interval when using low sulfur fuels and 200 hours when using higher sulfur fuels. These higher hours as compared to say 30 years ago are due to engine oil passaage design and lots of oil filter capacity.
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Old 03-23-2013, 12:12 PM   #158
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I'm on a serious search now to find out more about syn oil... before I actually try it out. Currently there is a 75% + chance that I will eventually try syn oil. Before this thread the chance was 10% -... Quite a turn in position!
I'm with you on this, Art. My chance of trying it on the next oil change is about 98%, however. I can see no downside in the experiment. Rest assured that I will photo/document things as they are now before changing to a synthetic.

For those who know me personally, it's projects, widgets, etc. like this that give me the biggest kick out of boating. (And besides, if I wreck my engine in the process, I'll be on Capthead's doorstep (swimstep?) with my lawyer. )
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Old 03-23-2013, 12:12 PM   #159
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I've got just a bit more time Craig S,

Not to be argumentative or overly critical Craig but I don't really think "cold starts" are bad at all. Heard it at least 100000000 times but never anything very scientific to support it. "cold oil will open the by-pass valve and cause unfiltered oil to flow into the engine" ........ never heard of such a thing.

The crank for 20 seconds to pre-lube is a great idea and have done that for years. Never crank for more than 10 seconds at a time though. I wait for about a minute between cranks.

Clean the fuel system? As in old fuel half gelled ect?

"carbon eats engines"? That's what I've been say'in but it's just what I've heard. But maybe I read it when I was a powerhouse operating engineer. Had lots of industry type magazines in the office. Re sunchaser's comments it seems the carbon goes through the filter and is harmless and not abrasive as I had thought. Perhaps it turns to sludge and sludge eats engines. In the powerhouse we had an in house oil "re-refiner" that filtered the used oil w a lot of heat, pressure and much filtration. It was cost effective as we were in the bush in western Alaska and it cost less to "re-refine" than to buy and ship.

So far what I've got out of this thread is to minimize even further the multi-vis oils I use and to consider getting a py-pass filter for Willy.
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Old 03-23-2013, 02:27 PM   #160
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I've got just a bit more time Craig S,

Not to be argumentative or overly critical Craig but I don't really think "cold starts" are bad at all. Heard it at least 100000000 times but never anything very scientific to support it. "cold oil will open the by-pass valve and cause unfiltered oil to flow into the engine" ........ never heard of such a thing.

The crank for 20 seconds to pre-lube is a great idea and have done that for years. Never crank for more than 10 seconds at a time though. I wait for about a minute between cranks.

Clean the fuel system? As in old fuel half gelled ect?

"carbon eats engines"? That's what I've been say'in but it's just what I've heard. But maybe I read it when I was a powerhouse operating engineer. Had lots of industry type magazines in the office. Re sunchaser's comments it seems the carbon goes through the filter and is harmless and not abrasive as I had thought. Perhaps it turns to sludge and sludge eats engines. In the powerhouse we had an in house oil "re-refiner" that filtered the used oil w a lot of heat, pressure and much filtration. It was cost effective as we were in the bush in western Alaska and it cost less to "re-refine" than to buy and ship.

So far what I've got out of this thread is to minimize even further the multi-vis oils I use and to consider getting a py-pass filter for Willy.

To start I think that argumentative and critical are good things in these posts, they only lead to more info There is so much data on cold starts I wont go there now but remember boats are not cars and the length of time between starts if a major factor, Pre lubing on the starter motor has many variables as to the amount of time to turn the starter, It can take 30 seconds for some engines or 10 on others, engine design and oil gauge location play a large part, I have bleed 1000s of diesels where The starter had to turn for over 30 seconds and yes starter cool down is important. As well as stored cranking amps and voltage. Now the carbon thing, Did I mention that carbon eats engines. Lets start with black oil, That is mostly from soot from incomplete combustion from the FUEL that is burning in the cylinders, The soot gets there from blow by gasses that push past the piston rings and thru the ring end gaps, Soot is small and softer than carbon and for the most part just makes a mess, The soot is usually smaller than the micron rating of most oil filters so it just recirculates thru the engine, some soot will coagulate in the oil filter to block the pores in the filter media over time, some diesel oils add chemicals to aid the bonding of soot, Now for carbon, Carbon lives in all hydrocarbon fuels cant get around it, Carbon is some really cool stuff in fact its one of the hardest substances known to this planet given enough heat and pressure, Now here is where carbon is not real cool, When a diesel is new and clean fuel is injected into a engine cylinder the fuel is atomised into a very fine spray that that mixes with the hot air from compression ignition to start the burn to expand the fuel into a gas under very high pressure and push down on the piston to make power, Now we have some carbon and some heat and some pressure, Most of the carbon will be exhausted thru the exhaust valve but not all, providing we have good clean FUEL, enough clean air, good fuel injector spray patterns and good cylinder ring seal the engine will preform fairly efficiently for a long period of time or predicted volume of fuel, here is where things start to mess up, Dirty Fuel or old out of spec fuel will start to foul fuel injector tips messing up the spray pattern and the fuel burn will suffer from incomplete combustion, Incomplete combustion forms hard carbon on the piston crowns and ring lands, Small chunks of this carbon foul piston rings and get trapped between the piston and cylinder causing rapid ware and blow by , This is the start of problem, There are other factors that cause carbon from incomplete combustion, Restricted air to the cylinder, not too much of a problem on non turbo boats and LOAD. For the most part on marine diesels the load is controlled by the size of the prop, If the prop is too big or fouled the piston drop is too slow for the expansion rate of the fuel, This is when you see black smoke in your exhaust , another form of incomplete combustion and the black is.... carbon, Now when I say that carbon eats engines its up in the cylinders and rings that are most effected not so much the engine oil system however there is still hard carbon that will end up in the oil system and create ware and clog oil filters.
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