reliability

[wardd]

which diesel in the 150 hp range naturally aspirated is the most reliable?

older is ok

[mydauphin]

Detroit Diesel 671 non turbo.... But can you take the weight. After that consider Cummings, Deere, Catepillar. All made of Iron... Aluminum engines or lightweight ngines less so. Checkout http://www.yachtsurvey.com/comparing_diesel_types.htm

[Ilan Voyager]

There is a lot of good engines in this category.

My experience gives me the Yanmar four cylinders among the best; rather light, very reliable, easy to maintain. Older, heavier and slower RPM do not mean automatically more reliable, but surely higher consumption and emissions. Reliability depends on the technology employed inside the engine.

Aluminum engines can go perfectly in a boat if you make the proper installation and do not mix metals. A lot of european boats use aluminum engines with no problems as most of the small diesel engines used in Europe descend from automotive or industrial engines, generally made in aluminum, which is the traditional metal for engines in european motor engineering. With the price of gas in Europe nobody uses gas engines except outboards.

The Yacht survey site has questionable affirmations on some issues (specially on sandwich boats). Any method when improperly built with poor craftsmanship will be a failure. This site is not the ultimate bible.

As you're in the States, the Cummins are good and have engines in your category. Most important is the rating you're asking to the engine, ie if it's for a yacht, a patrol boat, or a commercial boat. For a yacht is almost always better to get the lighter engine in for example the category Intermittent with a reasonable RPM (a 4400 RPM diesel is not a reliable engine...) . Less weight means less consumption, smaller tanks etc.

A very important factor of choice is the specific consumption at the cruise speed. That can make make many gallons of difference in the year.

[FAST FRED]

For my buck$ the question would be what type engine is available NEW , SURPLUS .

Since I prefer dry stack exhaust and keel cooling , almost an industrial engine is a candidate to operate a vessel

IF you are doing a new build its EZ, replacing an existing engine reduces the available choices if wet exhaust manifolds are desired.

For POWER , most marine engines are conversions of an industrial block , and all the mfg or converters will rate their engines at 4 levels.

24/7/360 for gen sets and trawlers or passage making vessels.
Some ratings have a 15 min limit at peak power (pleasure boat rating) and very reduced power levels for most of the time.

BE sure you know how much power you will need , and for how long , to assure satisfaction with your engine choice.

FF

[Crag Cay]

which diesel in the 150 hp range naturally aspirated is the most reliable?

older is ok
The answer to that exact question is undoubtedly the Gardner LXB in heavy duty configuration. They are still available but you need the space to fit one and the money to buy it!

This boat on brokerage has two fitted in a 'walk round engine room' and still has room to sleep ten! But then it does displace 80 tonnes.

[wardd]

dry exhaust, continuous duty, keel cooling, new build and there would be adequate space.

and easy maintainability is a plus.

[Crag Cay]

http://www.gardnermarinediesels.com/index.html

[FAST FRED]

Take a look in Boats And Harbors , its cheap subscribe if you must.

An example of adverts is ,

Sam Winer inc 330-628-4881

Daewoo diesel turbo 8-1L 177 cont as used in loaders and backhoe. new $6950

My choice International UT 466 NEW ..no price but a guess $5K. Oldrer DT's are pure mechanical, not as efficient as the electric injection but they will run after an electric storm.

There are dozens of advertisers and choices.A 6-71 Detroit would be a good choice used , not as efficient as a super modern engine , but they Die slowly and will get you home.

Gardner's are fine if you have displacement for about 3-4 tons of iron and $50K to spare.

Parts where you are cruising is a concern, In the USA the International or Detroit is my choice as an almost new DT 466 from a wreck is about $3K to $4K and fits a SAE Twin Disc gear box.

Boats & Harbors , do it.

FF

[peter radclyffe]

There is a lot of good engines in this category.

My experience gives me the Yanmar four cylinders among the best; rather light, very reliable, easy to maintain. Older, heavier and slower RPM do not mean automatically more reliable, but surely higher consumption and emissions. Reliability depends on the technology employed inside the engine.

Aluminum engines can go perfectly in a boat if you make the proper installation and do not mix metals. A lot of european boats use aluminum engines with no problems as most of the small diesel engines used in Europe descend from automotive or industrial engines, generally made in aluminum, which is the traditional metal for engines in european motor engineering. With the price of gas in Europe nobody uses gas engines except outboards.

The Yacht survey site has questionable affirmations on some issues (specially on sandwich boats). Any method when improperly built with poor craftsmanship will be a failure. This site is not the ultimate bible.

As you're in the States, the Cummins are good and have engines in your category. Most important is the rating you're asking to the engine, ie if it's for a yacht, a patrol boat, or a commercial boat. For a yacht is almost always better to get the lighter engine in for example the category Intermittent with a reasonable RPM (a 4400 RPM diesel is not a reliable engine...) . Less weight means less consumption, smaller tanks etc.

A very important factor of choice is the specific consumption at the cruise speed. That can make make many gallons of difference in the year.
gardner 8L3b

[peter radclyffe]

which diesel in the 150 hp range naturally aspirated is the most reliable?

older is ok
gardner 8L3B

[Carteret]

The International DT 466 is an excellent choice. Very commonly found in school buses across the USA.

[mydauphin]

gardner 8L3B

Darn and I thought my 6-71 was big....

[peter radclyffe]

Darn and I thought my 6-71 was big....
hello , are they detroit diesels, i dont know much about them, but they sound reliable, i replaced 2 of them in a 66ft commuter with aifos, only because the owner wanted them

[mydauphin]

YES, DETROIT DIESELS, I think they are the most reliable of all engines. Mine have over 15,000 hours been rebuilt 3 times, and have been on three separate boats. They still are fine. I know a guy with a WWII landing craft with the original Detroit Diesels still running. They are not highest HP per lb, or most efficient on gas, or quite, or clean. But they are above average on all. Also they are 100% mechanical, All I need is diesel, and some compress air, and they start... I don't even have turbos.

[Crag Cay]

DETROIT DIESELS, I think they are the most reliable of all engines
Without making this into a pissing contest, claiming to be the 'most reliable' is one hell of a boast.

The commuter ferries across the Solent to the Isle of Wight traditionally used Gardner powered generators that ran non stop. That's non stop for twenty years! Eventually it was stripped down for inspection and they found no discernible wear after 175000 hours. It was simply bolted back together and remained inservice on that ferry and then it's replacement.

The Kowloon Motorbus Company in Hong Kong always specified Gardner engines in their buses as each engine would out last the life-cycle of two coach bodies (25 years plus) The engines were then marinised and went to work in the fishing trawlers. Engines from the 1920 and 30's are still giving excellent service.

There's been no new Garners built in ages but demand is still sky high for these units and new parts continue to be made to keep them going. They are not everyone's cup of tea, plenty of new trawlers and ferries are launched these days with reconditioned Gardners in preference to any other marine engine available, despite having to pay more for the 'secondhand' engines.

[peter radclyffe]

YES, DETROIT DIESELS, I think they are the most reliable of all engines. Mine have over 15,000 hours been rebuilt 3 times, and have been on three separate boats. They still are fine. I know a guy with a WWII landing craft with the original Detroit Diesels still running. They are not highest HP per lb, or most efficient on gas, or quite, or clean. But they are above average on all. Also they are 100% mechanical, All I need is diesel, and some compress air, and they start... I don't even have turbos.
yes, considering the many problems with electrics, it may be that air start diesels are the most reliable, i remember a fishing boat that sunk in england,
they pressure washed & pumped her out, fired up the lister donkey engine by hand, filled the air tank & started the main, all in one day, hows that for reliability, in an age where too many things are unneccesarily complicated

[mydauphin]

I am not too familiar with Garners, haven't seen then around here in the States. From what your telling me they seem very reliable. The Detroit Diesels are everywhere by the thousands in all sizes and shapes. I am sure they have been far more popular and therefore cheaper to get. So I can get a 671 non-turbo in good condition for $5000, how much is a Gardner of say 250hp going for?

[Frosty]

It all depends what you are going to do with it. If you need to go to sea for days on end then you need a serious marine.

If you just want to go fishing in the bay when the weather is fine then back before dark then a 4200 RPM screemer in alluminium will do.

However I would never use electronic common rail injections stuff. Not on a boat, --your just asking for trouble.

With that in mind new engines are less reliable IMO, Caterpillar have gone this way,--

[Luckless]

Without making this into a pissing contest, claiming to be the 'most reliable' is one hell of a boast.

The commuter ferries across the Solent to the Isle of Wight traditionally used Gardner powered generators that ran non stop. That's non stop for twenty years! Eventually it was stripped down for inspection and they found no discernible wear after 175000 hours. It was simply bolted back together and remained inservice on that ferry and then it's replacement.

The Kowloon Motorbus Company in Hong Kong always specified Gardner engines in their buses as each engine would out last the life-cycle of two coach bodies (25 years plus) The engines were then marinised and went to work in the fishing trawlers. Engines from the 1920 and 30's are still giving excellent service.

There's been no new Garners built in ages but demand is still sky high for these units and new parts continue to be made to keep them going. They are not everyone's cup of tea, plenty of new trawlers and ferries are launched these days with reconditioned Gardners in preference to any other marine engine available, despite having to pay more for the 'secondhand' engines.

This might be a dumb question, but if the engines are so reliable compared to other makers, then why hasn't someone tooled a plant to reproduce new ones?

[Crag Cay]

Gardners are still available as remanufactured units but it's a niche market as they are (for any given horsepower) very large, heavy, expensive, slow revving, need big propellers, don't meet the emission requirements and are very, very expensive.

So few people are either prepared to pay for the engines or give up sufficient space in their boat to house such engines, as other manufacturers make units that are smaller, lighter, quieter, cheaper whilst being reliable enough.

But the OP question was "what's the most reliable?"

[apex1]

Sure the Gardners are, there are few other close to them though:

http://www.boatdesign.net/forums/diesel-engines/high-speed-low-speed-small-disp-diesels-25338.html

but that´s a very academic question today because all of them are extremely beefy and hard to find.
If you buy a DD 6-71 and spend some pennies on new injectors to downrate them to 150 horses, you have a engine forever. Grandpa´s technique though.

Regards
Richard

[FAST FRED]

Detroits are many folks choice as they are very versatile. They can be assembled to turn L or R , as well as assembled to have the serviceable parts on either side.

Figure 15 hp per cylinder for longest life at 1200rpm and about 20 at 1800.

30hp or more is for sport fish , that will accept a >1000 hour rebuild.

They come in 1,2,3,4 ,6,8,12,16 cylinder versions , and NEED to be loaded to a MINIMUM of 60%..

So if you need 60hp to to cruise get the 4-71 and prop it for 1200rpm.

NOT a bigger engine as the efficiency will suck.

Injector sizes can optomize output should slightly different outputs be required.10% change perhaps.

One of the biggest advantages I find in Detroit's is their ability to be put to sleep.

The Blower can mount on either side , so the unused side will have "air box covers".

Pull the covers and spray in fogging oil in every cylinder, turn the engine so every cylinder can get a good dose, and close up.

Airtight (aluminum foil and duct tape )the intake and exhaust , and the engine can sit for a season or year ,and with little effort be recomissioned.

Rip the duct tape off , and use a charged batt , you're underway.

Yes it will smoke like the dickins for the first min of operation as the fogging oil is cleared.

FF

[apex1]

Injector sizes can optomize output should slightly different outputs be required.10% change perhaps.


FF

Rating down Fred, you can adjust a DD to a much higher percentage, almost `til idle. Up is another field.

Regards
Richard

[mydauphin]

Like I said, they are great engines. Shame no one makes them any more. I know the US Navy and CG where buying just a few years ago.

[FAST FRED]

"Shame no one makes them any more."

WHO CARES??? with a few million of almost every configuration made , and parts EZ to come by , only the more modern engines ability to get a bit more HP for a gallon of fuel is against them

With a bit of looking Aluminum DD blocks can be found and set up for a fast cruiser.

Most Mfg. no longer MAKE each and every part for their engines.
The supply chain that produced the engine parts remains , even after the Mfg has moved on to the next generation of engine..

The biggest downside on a DD is the requirement for CF II 40 wt oil, not usually everywhere , and the labor required to replace injectors , and "run the rack" take a bit of skill not found today in most boat yards.

With the DD WWII training book, most anyone that is a mechanic can do a very workmanlike job of almost anything, up to a full rebuild.

There ARE specialized tools that are DD specific, if you are doing a rebuild.

FF

[mydauphin]

Fred the biggest problem I ever had with them is getting them to stop.

[apex1]

Fred the biggest problem I ever had with them is getting them to stop.

Well, as good as they are (have been), we should not forget they had their problems and disadvantages too! The awful number of parts in every engine, to mention only one.
After all the DD´s in total are not better than other makes.

Regards
Richard

[FAST FRED]

After all the DD´s in total are not better than other makes.

However "better" is as undefined and as much in the View of the operator as is "performance" or "economy".

For most boaters the ability to GET HOME is the most important concern.

An engine that DIES SLOWLY for most is "better" than one that just stops DEAD.

YES, the parts count is higher than a "modern " engine , but with constant refinement since 1936 , they are pretty reliable/available parts.

Personally I would never exchange a 20% better fuel burn for an electric injected engine that STOPS in a thunder storm.
And requires $5K of black box to start and run till the next lightning filled day. Which is Every day for 6 months of summer.

Were in FL, 100,000 lightning strikes a year .

FF

[apex1]

Fred

YES, the parts count is higher than a "modern " engine , but with constant refinement since 1936 , they are pretty reliable/available parts.

That has nothing to do with modern or outdated! The 2 stroke Diesel in general has the higher numbers of parts. And DD is the only brand of small 2 stroke Diesels.
And a DD does´nt die slower than 4 strokes.

Regards
Richard

[mydauphin]

I told this story before on forum, cant find it now. I was out on a older 54' Bertram. We where just 30 miles offshore when lightning hit us. A big one, it fried everything. VHF, Cellphones, generators, most batteries...Etc...
It was night, and about 8 foot seas. 40mph winds. So we are dead and bouncing up and down to the point that most were very sea sick. We had no flashlights handy, etc... One guy kept screaming, we are all going to die. We can very close to throwing him overboard.
Anyway after what seemed like an hour, we found a flashlight, got little portable generator going, found one out of four batteries undamaged and where able to start one engine a Detroit 1271. We had no gauges, or anything else. The lighting fried the panel, grounds. Only the compass and DD work. I was sold on DD then. No electronic engine would have started.

Since then I ran another boat where DD engine was waist high in water and it kept running. So when it came time to build my boat, DD with Air start.

I just need fuel and blow really hard, and they start. I can start engine from air tank.

[apex1]

Well, thats all nice, but every other engine brand or make would have done the same right?

[Frosty]

Yes electronic fuel injection on a boat is stupid. As for Gardner having more "parts count" than a modern engine? what do you have in mind. My wife calls them shiny bits.

Is this a private conversation what is DD? try not to abbreviate, other people don't know what you are talking about, including me.

[apex1]

Yes electronic fuel injection on a boat is stupid. As for Gardner having more "parts count" than a modern engine? what do you have in mind. My wife calls them shiny bits.

Is this a private conversation what is DD? try not to abbreviate, other people don't know what you are talking about, including me.

Frosty DD means Detroit Diesel, and the statement "more parts" was referring to them (two stroke) not to Gardners.

mydauphin
almost all major brands offer airstart as a option, but that has some drawbacks too, you know? At least in Europe the tank has to be tested and classed every second year. The compressor is either a permanently driven (additional noise, and power suction), or a separate one (cost and space issue).
Nothing is for free in our Naval environment.
And we should stop to compare the engines with electronic controls with those mechanically controlled.


Regards
Richard

[FAST FRED]

So when it came time to build my boat, DD with Air start.

Hydraulics can also be pumped up with a small air pump and TIME.

But be sure to include Murphy Switchgages , they are mechanical and will still be working AFTER the lightning side stroke , and with a battery pac will still serve as chief engineer , ringing an alarm or if you prefer securing the engine if your personally set engine limits are reached.

Use them on the noisemaker too, great insurance!!


and the statement "more parts" was referring to them (two stroke)

Some of the "more parts" are due to the individual cylinder injection pump.

In a Bosch style injection , if the pump dies , break out the tow rope , and the LLoyds Open Salvage Agreement.

On a Detroit Diesel (DD) failure of an injector (or its internal pump) simply means 20 hp less to come home with.

Each injector has its own rocker (like an exhaust valve has) so even at idle the rocker can be loosened to not operate the injector , should the need arise.

Also individual cylinders can be replaced , so damage is contained and repairs cheaper than a total rebuild .

FF

[apex1]

Some of the "more parts" are due to the individual cylinder injection pump.

On a Detroit Diesel (DD) failure of an injector (or its internal pump) simply means 20 hp less to come home with.
Also individual cylinders can be replaced , so damage is contained and repairs cheaper than a total rebuild .
FF

There are quite a bit more parts on a DD. A 4 stroke has about half of the DD´s. parts.
And many of the features mentioned above are valid for several other engines too, though 4 stroke. All old fashioned of course. Several of the old injection pumps (Bosch made) allow for individual setting at rest. Almost all of the bigger marine engines allow for individual cyl. replacement too.
Do´nt get me wrong, I was one who said the -71 series Detroit was a reliable engine. So, please do´nt draw a picture as if I was against them. But there are others (or have been) almost as good. And if we leave the -71 series, then DD is just one of many good (and sometimes not so good) manufacturers. The 60 for example is scrap.

Regards
Richard

[Frosty]

A diesel 4 stroke has 1/2 the parts of a Detroit diesel 2 stroke?

Your talking about the blower? can you be more specific?

1/2 the parts is quite a claim.

[mydauphin]

I think 1/2 parts comes in with blower and 4 valves per cylinder, and injector stuff, but it is all stuff that doesn't break except under extreme usage. The only way a DD (DETROIT dIESEL) fails, is wrong coolant, oil or over reving, out of control engine.

[apex1]

A diesel 4 stroke has 1/2 the parts of a Detroit diesel 2 stroke?
1/2 the parts is quite a claim.

Thats not a claim Frosty, thats a Fact.
There is the blower, a additional camshaft, followers, pushrods, more valves, actuator bar, additional fuel oil cooler, PTO housing and gear, and so on and on. All in all a DD has more than twice the parts of any other engine.
Therefore twice the possibility of failure or wear of parts.
It makes it just more impressive that these engines (we talk the -71 series only) are so well known for reliability. But as I said above "in general a DD is not better than any other prime brand".

Regards
Richard

[FAST FRED]

"The 60 for example is scrap."


Strange concept , the 71 series 6 & 8 would go 400,000miles to the inframe overhaul , and about 300,000+ for a couple more , when it would be pulled for a rebuild.

The Series 60 Detroits are regularly running 1,000,000 to 1,500,000 in over the road trucks before the first major service.

"SCRAP" , is a strange concept for this level of trouble free endurance.

Why the "Scrap" comment .Have YOU got less than a million miles from your fleet?

FF

[mydauphin]

DD followers and owners are a separate religion. I belong to several owners group and the level of loyalty is great. As long as the hp output of most engines is kept below a certain level all engines are reliable. That said the trend in recent years (last twenty..lol..) to increase Hp and make engine lighter has led to engine that are not as reliable as old big iron. That said, I don't like series 60, because I like old DD modularity and two stroke power.

Two strokes get more power per revolution. There is so much untapped potential in DD's. The series 60 is better for truck because they have wider and lower torque band. One of the little known secrets of two strokes DD's is that they like to rev. So much that they go crazy and explode.

Like I said shame no one kept upgrading them.

On a other note. If I had to put diesel engines on a coastal only boat, I might consider newer electronic engines because of greater tuneablity and less noise.

[FAST FRED]

Like I said shame no one kept upgrading them.


Unfortuniatly we are under the thumb of the Mother Earth Religion ,

so the Air Police And CO2 Warming Baloney has lots more to say about what engines can operate , and which can not.

The sad part is it is so expensive to "prove" an engine to the high priests of fantasy that the number of eng mfg is declining all around the world.

Soon we may be purchasing really efficient low cost Grey Market engines from the Chinese , instead of the first world mfg.

FF

[apex1]

Why the "Scrap" comment .Have YOU got less than a million miles from your fleet?

FF

Did this deteriorate to the "Trucker online" forum now?

I do´nt run a Truck fleet, and if, I probably would ask here:
http://www.dieselenginetrader.com/diesel_talk/
to get a first hand opinion!

But the topic was reliability of marine Diesel engines, right? And the 60 series DD is´nt famous for reliability.

Regards
Richard

Btw: ALL modern Diesel engines get out more hours on service than their predecessors!

[hartley]

I think the original question was for a used marine diesel in the 150hp range
the name Gardner came up ,an excellent choice ,big heavy slow running and i think thr 6lx was a bit shy of 150 hp ,but due to scarcity you will pay big bucks .then there was the detroit 71 series,plenty of these around and at bargain prices ,mainly because of the huge number made .Fast Fred has really hit the nail on the head here regarding the Detroits I agree 100 per cent with everything he has said ,there is a vast difference between owning and operating one and listening to hearsay rubbish .The only thing i would add is the smooth running and lack of vibration of the Detroits .My 3-71 in a wooden thirty footer ,HARD MOUNTED on big and long bearers bears this out
the reason for lack of vibration is the 2 stroke design and balance shaft construction .Where on earth did this nonsense of twice the parts in a Detroit 2 stroke originate compared to a 4 stroke design ,heaven help us ....
cheers hartley

[FAST FRED]

."Where on earth did this nonsense of twice the parts in a Detroit 2 stroke originate compared to a 4 stroke design ,heaven help us ...."

Armchair "experts".

FF

[apex1]

.Where on earth did this nonsense of twice the parts in a Detroit 2 stroke originate compared to a 4 stroke design ,heaven help us ....
cheers hartley

and:

Armchair "experts".

FF


Well gentlemen, YOU are the armchair experts here around!!!
In case of Fred I am a bit astonished though.
Hartley has delivered proof right here in his statements related with vibration.
and yes hartley ....heaven help us!

A Detroit Diesel engine has MORE than twice the parts of the average 4 stroke competitor!

And your local engine dealer would have agreed to that of course. But obviously you do´nt know any Diesel engine dealers to ask!

So, before you make idiotic statements about a boatbuilders knowledge here, you should improve yours!

[Frosty]

Apex --think you made a little mistake there.

FF called Hartley the armchair expert, you misquoted-- Oh what the hell what do I care.

[apex1]

Apex --think you made a little mistake there.

FF called Hartley the armchair expert, you misquoted-- Oh what the hell what do I care.

Did not understand it that way due to the plural. But if so, I beg your pardon Fred.

[hartley]

Apex you still don't get ti do you??? FF was referring to yourself as the "armchair expert'':) now to the main topic.on a previous post you said that there is an extra camshaft ,plus pushrods ,plus followers plus valves ,now tell me where they are I must have missed them the last time i looked .a camshaft without lobes?? very interesting. what you are probably referring to (who knows) is the BALANCE SHAFT which gives the detroit its smooth running characteristics ...pushrods there are NO extra pushrods ,why have a pushrod on a camshaft wiithout lobes????there are 3 pushrods per cylinder on detroit 2 valve head ,there are 3 pushrods per cylinder on a detroit 4 valve head ,as all valves open simultaneosly there is a bridge to operate 2 valves at once ,as there are no inlet valves ,you could say that there are less pushrods on a DD 2 stroke than a 4 stroke with a 3 or 4 valve head .I should add that one of the pushrods operates the injector ,no injector pump on a DD 2 stroke ,less parts, have you ever looked inside ,say a 6 cylinder injector pump ,you will find quite a few parts in there old son
Look Apex you are way out of your depth here I could go on here forever down to the last bolt and nut on a DD 2 stroke but I have no intention of doing so,it is quite juvenile,I know you will want to have the last say so go to it .....cheers hartley

[apex1]

Apex you still don't get ti do you??? FF was referring to yourself as the "armchair expert'':)
hartley

Well, the ability to read "old son" would help you understand some topic.
And where have you seen a statement like "camshaft without lobes" ? If you contradict to someone you should at least quote him correctly! Juvenile, yes!

And do´nt bother me with your agressive crap here. Just read the thread and contribute in a mature manner. Or better, leave it when your knowledge is´nt sufficient (as is obviously the case).

Ahh, and maybe David Pascoe can open your eyes a bit: http://www.yachtsurvey.com/comparing_diesel_types.htm

Richard

[apex1]

I think 1/2 parts comes in with blower and 4 valves per cylinder, and injector stuff, but it is all stuff that doesn't break except under extreme usage.

Would you be so nice to elaborate a bit here? You have them in your ER. Maybe the "juvenile" buys it from you.
thanks
Richard