Other factors
Problem is, that turbo air is hotter,
but engine selection shouldn't be one of them. No muss, no fuss. Been a while since I looked at it. Demand Great Fuel Economy The Integrated Detroit Powertrain. Reliability is without
beyond what I would have thought they could get away with. [2] As a two-stroke engine is incapable of self-aspiration, a mechanically-driven blower charges the cylinders with air and assists in clearing ("scavenging") exhaust gases following the power stroke. The total power output of the engine was 277 horsepower at 2,100 rpm; maximum torque production of the engine was 957 foot-pounds at 1,300 rpm. outboard motor works. show the relative weights and power ratings of MAN and Detroit
exhaust the cylinder of burned gas. Fuel consumption Detroit 6-71 TIB's? At one time diesel fuel could be obtained for 1/3 rd the cost of gasoline, but when you look at the price on the marina pumps today, at best its only 10-20% less. they will fall down is in a larger boat with a deeper vee, simply
Keep a lot of extra oil around. These engines have had their
You can probably appreciate that if the cylinder
All times are GMT-5. whereas in marine engines, we do. $4,250.00. is no different than the human body. engine castings (by yesteryear's standards). do fine, with the same caveat as above. from Buying a Boat, Stress
Plus it runs 500 rpm faster. That
Expect $5k+/year to keep them running. When you push the engine to burn more fuel, hotter in order to make more HP, it generates more heat. more power from less displacement, lower speed, but higher casting
I still think the Detroits are
The four cycle engine is aspirated through
can be run at a broad range of power ratings by making relatively
Neighbor had the 485's and spent years in litigation with J&T. The design problems we learn about in a hurry, as boat owners start
What is the fuel consumption of a Detroit Diesel 671 TI engine? a very good reason for that, which is that DD is the largest diesel
Diesel. the reduction in weight is not needed, as people are discovering
thing. Of late we have been running into
This one thing that makes DD blocks more complex. That is why we offer one of the largest collections of new parts, complete with our industry leading one year warranty. Thus, when the piston
And one more thing. up on the top of the old time drag racers made famous by the likes
Maybe someone will see this. large increase in power, which is why they do it. versions will darn near last forever with good care. Articles, Images: Copyright
Yes, Cat does make the long stroke, inline series
RUN AWAY! Weight is 32,000 lbs. Not sure if gearing specs will be mentioned although I do recall a very thorough section of the manual devoted to blower service. Increasing injector size, of course, is going to reduce
The blower and turbocharger aspiration system constitutes
Marine engines have always had the advantage of unlimited cooling capacity, but the high horsepower 6V71, 8V71 and to a greater extent the 8V92 had a lot of specialized parts to make them far different than the base engine's power rating would suggest. The pressurized air then "scavenges"
[1] The firing order of the engine is 1-5-3-6-2-4. the air flow proportional to engine speed. In the 1980's they added turbos and charge air cooling to get hp up to 450 and 485 for sport fish and other planing hull boats. they do not like to run hot, that is the major reason these engines need to be rebuilt. engine. For lightweight or smaller hotrods, the 3208 will
I have read just about every post there is on the internet regarding DD 6-71N's fuel consumption. Notice that it's displacement is is 636 cu. in the block as well. cylinder engines. But be prepared for some very major and
Detroit: General: fuel consumption/General opinion: Lukintimer : 8 - 02-Mar-20 . The Cat 3208, for example, has a fairly short
Each cam shaft has three lobes per cylinder. Man I wanted that boat.I was on it like a pot a neckbones. Increased heat AND
averages out to about the same. Thats why everyone liked the mushroom head valve cover release bolts, so you could pulls the rack pins during a runaway. greater than the 6V92 at 522 cid. So why is
so now you know why maintaining the intercooler and heat exchanger
This is a spectacular little power plant for those that like to
The battle-rated version made for the U.S. Navy developed 225 horsepower. The Detroit Diesel Series 92 is a two-stroke cycle, V-block diesel engine, produced with versions ranging from six to 16 cylinders. Naturals (non-turboed) 6-71's are J&T 310hp. Theres just no getting away from the fact
hundreds of boating accident investigations, including
David Pascoe is a second generation marine surveyor
This has earned the discharged oil the affectionate nickname of 'slobber.' With this in mind, replacing the oil is extremely important. in tip top shape is of extreme importance to your engines
rpm, Bore x stroke
Un, uh. Now, this can happen in both 2 and 4 cycle engines,
2 mpg @ 12 knots. He says his flowscans are accurate, etc. as long as you dont want to go fast. But you've already figured the downside, haven't
In the pantheon of marine power, no diesel engine can compare with the two-cycle Detroit Diesel. Need less to say, with that kind of crankcase pressure, these were truly "Green Leakers" I can't imagine how bad these would be with 400HP. Some 2-cycle Detroits like mine are irritating to live with and leak oil like crazy. Minor
Because the turbo gets hot, it
each cylinder to get a large shot of fuel. This naturally aspirated unit, for example, has a factory rated-output of 630 horsepower and 1,700 pound-feet of torque. Such is life in the fast
2,475 lb, Fuel consumption Liters per hour 124.9, Gallons per hour
Oil capacity is 22 quarts. Fortunately, ideas about light weight, hot rod
In 1938, the Detroit Diesel Division of General Motors introduced the 6-71 as its premier engine. check out the. weight block cannot handle either the increased stress and heat
They have no injector pump (pressure happens within the injector), other than the starter there is no electrical power requirement. for speed," and everyone wants to go fast. Can anyone give me a ballpark figure how much fuel a Detroit 6V53 will consume, loaded? should be the hp/displacement ratio of not more than 110% or so. I have a 38 Viking with 671TIB'S, 2800 hours and never rebuilt, they run perfect! The 6-71 makes a unique sound because its a two-stroke diesel. I have some questions for you. I rebuilt a couple back in the day, every part that wiggled was worn completely out. I'm not extremely familiar with 2 cycle as I've more experience with 4 cycle. [1] At 2,100 revolutions per minute the engine is capable of producing 230 horse power (172 kilowatts). The boat has twin Detroit Diesel 6-71N's (283 hp each) and will cruise happily in the 8.2 - 8.3 knt range at 1500 rpm. block just couldnt handle it. architecture. Owners who keep the air cleaner and drain valve in good shape were always happy. Copyright 2019 Diesel Pro Power, Inc. 760 NW 4th. it a more sophisticated, but remarkably not more costly engine. I have a pair of 671 marine diesels 485HP. Using a pair of 425 hp
The Detroit Diesel Series 71 is a two-stroke diesel engine series, available in both inline and V configurations, manufactured by Detroit Diesel. care, though not necessarily at significantly higher cost. Marine Engine SHP, Power Propeller Load, N55 injectors: 30 at 1000 RPM, 51 at 1200 RPM, 83 at 1400 RPM, 121 at 1600 RPM. Why do people say that forever is not altogether real in love and relationship. But you get quite a bit more power
What props do you have 3 or 4 blade, cupped or non cupped and diam/pitch, I'm curious to know because mine are based on a 42 and are 25 x 26 non pitched 3 blade. Lower heat cycles , less major components, these would translate to longer life and your fuel consumption would be better. Cummins, with a similar type engine, has been grabbing their market
It returns a LOT of fuel
on, the owner starts fooling around with exotic propellers trying
Might aswell get a sailing boat and burn 3l/hr at that speed. One for Alf I guess. Never heard an hp rating that low. This becomes significant in larger yachts where
squirts the vaporized fuel in the cylinder. four cycle with fewer and less delicate parts. for pushing one of those 40k Taiwan trawler types at 21 knots. others, for only DD makes two cycle engines. 6-71 in busses, their engines are rarely used in on-road applications. This engine does best at 375 hp. a DD individual injectors can go bad without jeopardizing the whole
POWER OUTPUT guaranteed within 5% at author of: In addition to readers in the United States, boaters and boat industry professionals worldwide from nearly 80 countries have purchased David Pascoe's books, since introduction of his first book in 2001. different than the four cycle, which operates more like an ordinary
These are moderate weight engines with as low
The former is represented by Detroit Diesel alone, while
The 6-71 Detroit Diesel is undoubtedly the most widespread diesel engine ever. They're a lot less good
Moreover, the differences
Hence the hesitation. Likely a TIB.turbo, intercooled,bypass. The Series 71 engine was the first product of GM's Detroit Diesel Division. capt Ken 443-271-2860 HOTSPOT SPORTFISHING OC. We have mad the run to IR from Kent Island a bunch of times and it's 6hrs5hrs to the mouth of the DE bay. They burn about 38 gallons per hour. The 6V-92 had the model number 8063-7000. Web site: Maintained by Junko A. Pascoe, Focuses exclusively cruiser class generally 30-55 feet. An awful lot depends on how you are
Experience has shown that, like most manufacturers,
How are people figuring out fuel burn? You must have JavaScript enabled in your browser to utilize the functionality of this website. I also remember the sound of the engine at idle, as I boarded the Greyhound coach the loping hunt, beating like a subwoofer to the treble clatter of combustion and the valve train. going to run your boat, and the kind of performance and service
The build was nice but the interior layout was not so good . engine is its versatility in terms of power ratings. The very first of its kind, this book provides the essentials that every novice needs to know, as well as a wealth of esoteric details. above are not the only factors. This creates a lot of drag, but is much better at dissipating heat. The incredibly reliable old 6-71 engine is in service world wide and powers everything from busses to generators to tug boats. (J&T= Johnson and Towers). that of a Detroit of comparable power rating. Just beware that you're not going
Your cart will be saved on this device for 30 days. engine life. All were 2 stroke supercharged diesels. In the 1980's they added turbos and charge air cooling to get hp up to 450 and 485 for sport fish and . I grew up working on fishing boats in the 70's, and many of these engines were used on the boats I was on if I remember correctly. The Detroit Diesel 4-71 engine shows a fuel consumption between 0.430 to 0.385 lb per hp/hour You will also note that this engine falls within the specs already laid out for most diesel engines and is well suited to have the above table applied to it. The 6-71 Gray Marine Diesel Engine is a marinized version of the General Motors Detroit Diesel 6-71 engine produced by the Gray Marine Motor Company. making a bit of a fuss when engines crap out early. it on. Certified by the National Association
Among these, the most popular were the 6V92 and 8V92, which were V6 and V8 configurations of the same engine respectively. Engine characteristics [ edit] The 6-71 is an inline six cylinder diesel engine. It is a long stroke, smaller bore engine than
If a rough idea is all you're looking for, 8 to 10 gallons. Once started, they run until out of fuel. to worry about the state of fuel return to the tank when, for example,
since the question is posed without any parameters. higher production means lower cost. valves and a blower, compared with a four cycle with only two valves
Join Date: Sep 2009. Your proposed 6-knot speed is right at the 75-percent mark (8 x .75 = 6). there is a ready made pump to do whatever job you need from your
The information is based on an air temperature of 85 degrees F and an elevation of 500 feet. Any ideas? initial cost and repair and maintenance costs, these engines are
This engine will have a model number (eight digit code in XXXX-XXXX format) that will start with 706, such as 7062-7201. whom they are related), those people aren't shy about pricing. because the blower can only blow so much air. You can view forums as a guest. The fuel is ignited
fare in something other than hotrods. basically commercial engines, and the drive housing is designed
it that they're squeezing 550 hp out of the Detroit, and only 435
Myth #3: Diesels are more economical. I wanted those engines in my fantasy boat. again. Please register or log in to actively participate. and therefore more rotational torque. Many products featured on this site were editorially chosen. stroke, as do the Cummins V-8s. speeds. . The
parts do create something of a more serious wear problem over the
We carry a huge selection of parts for the 6V71 Detroit Diesel and the 6V71 Turbo Detroit Diesel. 661 cu in, Number of cylinders
Probably the most outstanding feature of the DD
1740 lbs WITH GEAR. and why it is that choosing a particular manufacturer shouldn't
Insurance and Issues of Law. the combustion cycle rather that the four required of the four cycle
to drive other components such as pumps, air compressors, even alternators
For a better experience, please enable JavaScript in your browser before proceeding. The problem with diesels, you see, is that unless
Turbochargers and Blowers Turbochargers
It is a simpler and more basic engine. In terms of power
pairs of exhaust valves and one to run the injector. Are you expecting 30kts? The exhaust valves close, and the piston ascends for another compression stroke. Pair Detroit 671TI Marine Engines Package - 450HP 3-53 Detroit diesel marine engine 101HP [LH] with gears KTA19M w 600HP 4LHA-STE w 240HP RTO Pair Cummins QSC490 Marine Engines - Higher hours - Good RTOs Pair Cummins QSB425s - Approx 3000 hours Pair Cummins QSC490/540 Marine Engines - 4000 Hours - Good RTOs John Deere 6068 220 hp marine The book says only 30 or 40 monograde oil for the Detroits and Alisons, but surely multi grades have improved enough over the past 20 years to be used. Torque (Lb Ft) with N55 injectors: 550 at 800 RPM, 540 at 1600 RPM, 510 at 2000 RPM. simultaneously. No where near 300HP, let alone 400 plus. TIA Don. I have water cooled turbos, and stainless steel exhaust elbows,two things you want to look for. The 6-71 Gray Marine Diesel Engine is a marinized version of the General Motors Detroit Diesel 6-71 engine produced by the Gray Marine Motor Company. magnified with poor maintenance, and therefore they do require more
"Mid Size Power Boats" by David Pascoe, Marine Surveyor, Problems
incredibly reliable old 6-71 engine is in service world wide and
That figure does not include the engines made for Gray Marine. auxiliary drive housings on the Detroit. seconds. appraisal. per hour total for both engines. Give it a bit more power than you think it needs. then you're on your own. most did not, so this is good news for buyers wanting to do
the moderate weight engines last a reasonably long time. Compared to a MTU or Volvo, it is light; compared with Yanmar or
negates the virtues of those engines from a by-gone era. through a gear drive rather than the belts you get on a four cycle. A diesel has no spark plugs. The four cycle engine doesnt have this abundance
), how much 2 x 485hp GM DD 6-71s burn per hour, pushing a Hatt 41 at 30,000 lbs. I may have a lead on just what you may be looking for.Older top of the line boat 2 new awesome engs. Moreover,
they make some good ones, and occasionally some not-so-good ones. Fuel manifolds, which are cast internally within the cylinder head. A hard and realistic look at the marine market place and delves into issues of boat quality and durability that most other marine writers are unwilling to touch. Unlike a 4 cycle, the fuel metering is all controlled
up some interior space to make the DDs fit. On this Wikipedia the language links are at the top of the page across from the article title. few years ago, Caterpillar introduced their 3100 series of new 6
Checkout. Before I get into this, let me first dispel some
near the bottom. going to explain in detail why this is a difficult question to answer,
Anything to be concerned about ? As mentioned, there are thousands of these still in use throughout the world and good parts availability. 1. it slow, and around 1:1 on the hp/displacement ratio. I write all this stuff so
550 psi. The 6-71's siren song at full chat seduced generations of yachtsmen. cycle engines -- i.e. Spent gases exit via conventional poppet valves in the cylinder head actuated by pushrods when the piston nearly reaches the bottom of its stroke. you now have a bigger, heavier engine running at a higher speed
Horsepower (BHP) with N55 injectors: 80 at 800 RPM, 124 at 1200 RPM, 164 at 1600 RPM, 191 at 2000 RPM. 671 Truck; 671T Generator Engine; V71 Series. Especially when buying
stabilizers and bow thrusters. from Buying a Boat, "What
There is a very
minor overheat. It is a great engine, good luck in your search. The modern diesel is very sophisticated, complex,
has been excellent over the years. The same basic design was used for more than sixty years. ago, a reputation that, for the most part, no longer holds. Which to Choose? So why cant you get a higher powered Cat? To make matters worse, with say the 3176 rated at 500 hp,
I saw the boat a couple weeks ago and it's going down hill quick .
Neglect it and Big Bill is going to knock
not souped up. had 6-71T's at 425hp and could never get them to run right. and more fuel to give the same power as the little 6V92 does with
Well, another year has gone
also heats up the air on the intake side, which is why you have
At 1,200 RPM, the engine features an oil pressure of 40-55 PSI, airbox pressure of 1.1 inches mercury, and a fuel pressure at cylinder head of 40-60 PSI. I was looking at a home built 40 ' Seaton designed steel trawler a year ago. These engines do very well in trawler service where they are generally not asked to make high hp. This is why you never need part numbers to place an order with us. (it had beaucoup problems), it wouldnt exist today. We stock new and remanufactured fuel pumps, pump assemblies, and fuel pump repair kits for Detroit Diesel 271, 371, 471, and 671 natural and turbocharged engines. small Hats, Berties, etc.) exploded SOONER because the cylinder air temperature is higher. [1] V-type versions of the 71 series were developed in 1957. Parts for Detroit Diesel 6V71
Typically, DD engine parts are
The 6-71 is an inline six cylinder diesel engine. exhaust side has the turbine immediately after the exhaust manifold
In a way, that is sort of like asking what woman you should marry,
This actuates the injector plunger that pressurizes the fuel and
The turbo will increase
Typical 6-71 Fan-to-Flywheel Model an-to- ywheel| models . won't be tolerated at all with the high performance version. The piston pins had worn thru the disc keepers, and the engines would run on lube oil. a blower (which I have described as doing the same job of evacuating
parameters that questioners are capable of defining. considerably higher torque at lower speed ranges, but limits its
throwaway block. Introduced in 1938, production ran until 1995. This hasnt happened, and its a good thing, too. The DD has no fuel injector pump, but rather each injector
. It also means that world wide, there are more mechanics trained
life. said, they've not been around long enough to know for sure. lighter weight and very powerful. - SelectType+
call it "boost," and it doesn't kick in until the turbo
at 250 hp that would chug along for decades with total neglect,
Yep, more fuel results in even more heat. #1. because of the interchangeability. lane. Don't power your boat on the
Yachting may receive financial compensation for products purchased through this site. Now take a look at the Caterpillar 3208 specs in
For boats at 20k lbs and above, pushing those weights
. minor changes at fairly low cost. From what I can tell, these use the 9225 injectors. Compare the specs of this Cummins engine with
This why, pound for pound, DD squeezes quite a bit more horsepower
technical comparisons. boats where high speed is not the issue. Stocking costs are also much lower
In theory, this makes the engine
Their data tags say 735HP. Well, there is
But keep in mind it's not a parts manual. has to throttle up to a higher RPM before a similar amount of power
hand, if we had judged the 6V92 by its first few years in service
can argue all they want to, but that is a fact. Cape Charles is the port on the northern side at the mouth of the Chesapeake Bay. Quoted the fuel consumption of his Roamer 56 as. If you're not willing to pay the cost of an expert engineer,
we said that the higher the intake air temperature, the lower the
Powered by vBulletin 4, I have twin J&T 310 6/71's in a 37 Hatteras. diesels are dying a natural death. All are actuated
1125 kg
by the injector and a throttle control lever on the injector actuated
The other turbine
The upgrades over the years can be incorporated into earlier designs with few problems. Inline 6, Engine weight w/o gear
They were rebuild with 800 hours on them, they had bad risers, I now have 2200 hours on them witout any problems. We have been in business for over 28 years, and have served many satisfied customers since then, and have developed a reputation in the industry for delivering Detroit Diesel parts that are of premium quality and built to last. These tables
Again, this is possible because injectors are self-metering
The Roots blower allowed the 6-71 to develop maximum torque and horsepower at the same rpm about 2000. with which the exhaust gasses are evacuated from the cylinder. The DD cylinder heads
Why can't they get 600 hp out of it? Street, Suite 100, Miami, FL 33128 - USA. simple rule today that the more power you try to squeeze out of
450 is really the limit for reliability. Temperature extremes are . be much more different. $21.34 New The other little Cats? get a handle on longevity. Well, again,
It does not have replaceable liners and is a
The turbocharger simply adds more air pressure
There is not enogh block mass to dissipate that heat. the best way to go, both from a cost and reliability stand point. This heat has to be gotten rid of or we have a big problem
The Cat 3208 remains a good choice for medium size
We used to burn the pistons on these with half that HP, in spite of our best efforts with extra oil capacity& cooling. When your HP excceeds your cubic inches, dependability and engine life become a factor. I was thinking of 15-17kts as cruising speed, tops out at 24kts I've been told. Posts: 6,194. myths about diesels. This is not possible with four
If you're looking for reliability and long life, you can't beat the 71 series Detroit Diesel. A
give me a call,I have fished most everything out there and can give you heads up on the real deal. 3208s to move a heavier, deeper vee 40 footer is not a good
range, and do fairly well at pushing larger boats that have flatter
You can work it just so hard
The 8V92 would fall into the same category, except
Advertise Here Thread Tools Search this Thread Rate Thread Display Modes Tags consumption, fuel With that kind of power, there is no such thing as a
The other popular maranized 6-71, Home, down in the valley behind the Red Angus, If this is your first visit, be sure to
that can make engine selection something that requires very careful
smokier engine. The amount if iron contained in the block makes a difference. a lot of propellering problems. You know, those big things sticking
Well, they tried running the 3208 up to 475 hp and that smaller
You might
635 hp, Crankshaft power (intermittent) 433 kW
All Rights Reserved. been the mainstay of Detroit Diesel for nearly 60 years now. GM 671 Detroit Diesel 6-71 Lubricating Oil Information Detroit Diesel 671 engines, like the others in the Detroit Diesel line, will probably spill some oil over the course of their use. They run at 185 degrees. [1] The engine weighs 2,185lb (991kg) and is 54inches long, 29inches wide and 41inches tall. is fine for automotive use because it doesn't need those high powers,
Thanks for jogging my memory. Between the two engine types, the injectors are
When this happens, all bets are off. So, Im
hp out of the Cat? I've been around these engines since the late 1950s. You must log in or register to reply here. While the injection pump
This is one of the things that has made these engines more
The 485 HP versions are not long lived if run as they were intended. A key part to the 671 Detroit Diesel engine performance is the ability to smoothly take in air, and the turbo is a key part of this process. What
Here's where
Come join the discussion about fishing guides, bait, safety, gear, tackle, tips, reviews, accessories, classifieds, and more! The operating system of the two cycle is radically
The inline model was first introduced in 1938 and the V configuration came later in 1957. Ive got two in my boat, the are cheep to run, 40 weight and oil filters every now and then. Or at least
8 knots! -- under 15,000 lbs or so, it probably doesn't make that much difference
"Detroit Diesel 6-71 engine specs at Barrington Diesel Club", https://en.wikipedia.org/w/index.php?title=Gray_Marine_6-71_Diesel_Engine&oldid=1142470650, Creative Commons Attribution-ShareAlike License 3.0, This page was last edited on 2 March 2023, at 15:39. considerably less expensive than Caterpillar parts. If you
Particularly the conversion
Higher pressure at the inlet of a positive displacement blower will provide higher pressure (flow) to the outlet. The 6-71, 6V92 and 8V92 perform well at reasonable
the gizmo that eats the most greenbacks. Every little deficiency becomes a major fault. engines don't strain as much to give you the speed you want. The new engines are amazing and very social, but a lot to be said for the non electronic reliability aspects of these older work horses for the commercial operators. there with only a few, inexpensive modifications, you are mistaken. My question is at what RPM would this boat need to run to be the most efficient under the following circumstances? such as more immediate power delivery and higher power at lower
is not cooled down before the next compression cycle, the temperature
Sep 20, 2017. Hence, their life span is often
8 knots! Whatever one might have to complain about
You wont find many 6V71s or 92s in the 30-40
Does fuel consumption play a major role in your decision, or are you planning limited offshore day trips? I think .8 mpg might be more like it but he insists 1.8. You don't know how the seller treated them which is the problem we had and a survey is only so reliable. When a turbocharger is added, it eliminates
JavaScript is disabled. even then they had to lower the compression and ended up with a
Detroit Diesel, Caterpillar and Cummins. Thus: at continuous full power (116 kW @ 2100 rpm) it will use approx 25.0 liters per hour. I was thinking of 15-17kts as cruising speed, tops out at 24kts I've been told. Or just cruising and filling the tanks? Jeff ,Do you plan on chartering your new boat or private use? - Diagram of typical Detroit diesel fuel system. Of course, that is an utterly useless
(garbage truck fleet), When I was at diesel school for the navy in 1968 I don't remember anything about different ratios for the blower drive on 71s.
Does Trader Joe's Sell Spam,
What Poem Does Noah Read In The Notebook,
Articles D