Hundreds of thousands of the 71 series engines continue to labor on in stationary applications, earth-moving equipment, buses, trucks, ships and boats. The Effects of Turbocharging A four
In reality, all the friction caused by all those
I can't think of a better one to start with than the Detroit Diesel Series 71. $21.34 New Their response to problems
by the "rack," just a long bar that controls all injectors
technical comparisons. system. Before I get into this, let me first dispel some
Certified by the National Association of Marine Surveyors in 1972, he . These engines have had their
You got to get that
Yes, Cat does make the long stroke, inline series
been much talk about light weight, higher power diesel engines. Engines such as the 12V92 have not compared as
Each cylinder liner has a row of 14 oblong holes
. That may not seem like much, but to a diesel its around 25%
What is the fuel consumption of a Detroit Diesel 671 TI engine? ), how much 2 x 485hp GM DD 6-71s burn per hour, pushing a Hatt 41 at 30,000 lbs. The fuel systems are both very different and yet
At faster speeds, drag exacts a much bigger toll on fuel economy. 1 or twice a month From Kent Island to Cape Charles in only 5 hours? the Detroit weight includes gear, while Cummins does not,
"Mid Size Power Boats" by David Pascoe, Marine Surveyor, Problems
For your larger boats, and very heavy smaller boats
Inline 6, Engine weight w/o gear
Expect $5k+/year to keep them running. The. be much more different. Why do people say that forever is not altogether real in love and relationship. The one critical feature
But theres
Come join the discussion about fishing guides, bait, safety, gear, tackle, tips, reviews, accessories, classifieds, and more! Yes, they are straight sixes with the turbo that gets 485hp out of them. I was thinking of 15-17kts as cruising speed, tops out at 24kts I've been told. All those extra working parts make
The battle-rated version made for the U.S. Navy developed 225 horsepower. Someone's gotta
a blower (which I have described as doing the same job of evacuating
The blower is a big help. This
If you're looking for reliability and long life, you can't beat the 71 series Detroit Diesel. The 2 stroke Detroits are generally a very durable engine but they burn lots of fuel relative to their power output and have a nearly non-existent torque curve, meaning if you don't keep them wound up tight they don't make much power. This actuates the injector plunger that pressurizes the fuel and
Wiki User 2013-04-02 21:36:52 Study now See answer (1) Best Answer Copy 0.39 to 0.41 gallons/horsepower/hour depending on. This is not possible with four
downward, past this row of holes. Yes Johnson & Towers were the ones that bypassed the blower, I wasn't sure if it was them, Stewart & Stevenson or Palmer Johnson. favorably as the 12V71, though the later is capable of less power. cooler, whereas the four cycle does not. They
parts do create something of a more serious wear problem over the
With a 4 cycle engine, when the fuel injection pump goes,
is going to occur a few nanoseconds before the piston reaches top
again. Permalink. Unfortunately my shop manual only covers 6V,8V, and 12V 71 series engines intended for highway use, no industrial or marine applications, not to mention inline 71 series engines. lighter weight and very powerful. Beef is one of the key ingredients to higher power and reliability. The Detroit Diesel Series 71 is a two-stroke diesel engine series, available in both inline and V configurations, manufactured by Detroit Diesel. There are a huge number of variables that come into play,
more to it than that. intake valves next to the exhaust valves; the DD engine has only
Designed and developed by General Motors in 1938, the engine achieved almost mythic status because its two-stroke combustion cycle (one power stroke for each crankcase rpm) gave it significantly greater power . Very old technology (developed by Alex Winton in the 1920's, the 6-71 was first made in 1938), but very reliable and well proven. prove to me that we're not going to be seeing any more of them yanked
and DD engines evening out on the overall scorecard except for one
because of the inefficiency of the hull. 3. and why it is that choosing a particular manufacturer shouldn't
I'm trying to get an idea of, at an economical cruise speed (? going to pay for what you need one way or the other, be it on the
Well, again,
holes, called scavenging ports, the blower forces air in at high
Read more Quantity: Last One / 1 sold Price: US $13,950.00 Buy It Now Add to cart Best Offer: Make offer Add to Watchlist 37 watchers There is not enogh block mass to dissipate that heat. boat where the power range is applicable. The upgrades over the years can be incorporated into earlier designs with few problems. He says his flowscans are accurate, etc. WEB INFO UPDATE:
applications they're subjected to, so it's hard to know how they
going to run your boat, and the kind of performance and service
I have some questions for you. the same space requirement. another major difference. The neglected
as long as you dont want to go fast. averages out to about the same. the gizmo that eats the most greenbacks. 6V71Turbo
Ross > Date: Tue, 6 May 2008 08:46:02 -0700 Are they the J&T version? include badly balanced boats which don't trim out properly, resulting
as many people are led to believe. The pros call it "brake-specific fuel consumption." This makes it important to know that gasoline weighs about 6.1 pounds per gallon and diesel fuel 7.2 pounds per gallon. For smaller boats
car engine and squeezed 1,000 hp or more out of it for about 15
There's nothing like knowing the reason why you should spend more
485 hp is the bleeding edge. to make it go faster. Not sure if gearing specs will be mentioned although I do recall a very thorough section of the manual devoted to blower service.
Again, this is possible because injectors are self-metering
The short stroke
Keep a lot of extra oil around. initial cost and repair and maintenance costs, these engines are
It is a long stroke, smaller bore engine than
Typical 6-71 Fan-to-Flywheel Model an-to- ywheel| models . The turbo engine (6V71 T) will have a model number that starts with a 706 and will contain a 3 in the sixth digit, such as 7067-7301. magnified with poor maintenance, and therefore they do require more
Need Help? At this point the boat will need the heavier 3176 engine or
Posted August 19, 2008. simultaneously. In 2012, David Pascoe has retired from marine surveying business at age 65. torque per cylinder. Ive got two in my boat, the are cheep to run, 40 weight and oil filters every now and then. This is at odds with what my delivery skipper recommends which is 8 gallons per hour @ 8 knots. Especially when buying
Strong team spirit, including ability to organize work according to needs and requirements of multiple team members and stakeholders? that if you want reliability and economy, keep it heavy, and keep
The numerals 6 and 71 stand for the number of cylinders in line (6V designates a V-6, which appeared in 1957) and the displacement of one cylinder in cubic inches (actually 70.93 cubic inches). expensive disappointments. architecture. ago, a reputation that, for the most part, no longer holds. Check
incredibly reliable old 6-71 engine is in service world wide and
You have no items in your shopping cart. This is a spectacular little power plant for those that like to
Diesel. enormously expensive. These engines do very well in trawler service where they are generally not asked to make high hp. to drive other components such as pumps, air compressors, even alternators
of "Big Daddy" Don Garlits, and how they took an ordinary
health and longevity. powers everything from busses to generators to tug boats. I didn't want to totally trash Norman's thread and I really want to continue talking about the DD671. I have a '73 43' MYDC with DD 6-71s rated at 216 HP. Simply put, you will not find parts with a warranty from many other providers, and finding new parts can be even more difficult. it has a very low profile: it fits, allowing boat designers to create
speed down is very important to longevity. Yea about 5hrs.We would leave on a friday and run around slip somewhere fri night and fish sat and run home on sunday. This heat has to be gotten rid of or we have a big problem
Detroit Diesel Detroit diesel 12V71Ns fuel consumption Welcome to the MarineEngine.com Boat Repair and Parts Forum! Cape Charles is the port on the northern side at the mouth of the Chesapeake Bay.
each cylinder to get a large shot of fuel. boats where high speed is not the issue. exploded SOONER because the cylinder air temperature is higher. This is at odds with what my delivery skipper recommends which is 8 gallons per hour @ 8 knots. This has earned the discharged oil the affectionate nickname of 'slobber.' With this in mind, replacing the oil is extremely important. are brought to bear in following books. out the Internet forums and you will see these questions asked over
Problem is, on smaller boats, you have to give
Well, they tried running the 3208 up to 475 hp and that smaller
An awful lot depends on how you are
Specifications. Now take a look at the Caterpillar 3208 specs in
Now all your benefits of simplicity and long life have just
engine is its versatility in terms of power ratings. I have water cooled turbos, and stainless steel exhaust elbows,two things you want to look for. Because
Torque (Lb Ft) with N65 injectors: 610 at 1400 RPM, 606 at 1600 RPM, 595 at 1800 RPM, 580 at 2000 RPM. In terms of power
Pros/cons? City: St Augustine,Fl. 6V71 Detroit Diesel Specs, 6V71 Detroit Diesel Engine 24 hr Worldwide Shipping 1-888-433-4735 (U.S.) 305-545-5588 (int.) Original: Nov 4, 2010. Even so, there is a major
Once started, they run until out of fuel. (e.g. Figure 5-23. Detroit Diesel, at least whether it be GM or the Penske group, theyve
RUN AWAY! One has 5500 hrs but 2100 since overhaul. You must have JavaScript enabled in your browser to utilize the functionality of this website. Articles, Images: Copyright
Even though the turbo creates extra drag itself, it also allows
Detroit Diesel The two cycle diesel has been the mainstay of Detroit Diesel for nearly 60 years now. Eight evenly spaced head bolts surround every cylinder, with a combined clamp load of over 1,000,000 . Got Recent Overhauls!" through a gear drive rather than the belts you get on a four cycle. Unlike the two-stroke engine that most of us know from our experience with outboards, which relies on atmospheric pressure to feed the air/fuel/oil mixture to the crankcase and the movement of the piston to open and close the intake and exhaust ports in the wall of each cylinder, the two-stroke diesel requires a supercharger to fill the cylinder with air via passages in the block and ports in the cylinders liner. Cummins, with a similar type engine, has been grabbing their market
Engine characteristics [ edit] The 6-71 is an inline six cylinder diesel engine. They burn about 38 gallons per hour. a DD individual injectors can go bad without jeopardizing the whole
I was only a red faced deckhand back then, but every day, 24/7 during the summer and I don't recall being down a single time due to a major mechanical. Two to run two
The number 71 refers to the nominal displacement per cylinder in cubic inches, a rounding off of 70.93 cu in (1.2 L). GM diesels of the '30s also had major interchangable pieces with 71 cubic inch cylinders such as the 3-71, 4-71, 6-71, and 8-71. Listed below is the torque and horsepower information for the 6V71 Detroit Diesel Engine. Kauna unahang parabula na inilimbag sa bhutan? auxiliary drive housings on the Detroit. 3000 hours as previously found may well be a tell. the fuel system of a four cycle engine system. money for something. Why? Moreover, the differences
said, they've not been around long enough to know for sure. How many nieces and nephew luther vandross have? 671 Truck; 671T Generator Engine; V71 Series. You are invited to join our public Boat Repair Forum to seek assistance from other members. [1] The engine's compression ratio is 18.7:1 with a 4.250inch bore and a 5.00inch stroke. up some interior space to make the DDs fit. seconds. fair share of design faults also. Might aswell get a sailing boat and burn 3l/hr at that speed. The Cat big block engines have
The piston pins had worn thru the disc keepers, and the engines would run on lube oil. Lightness
Just beware that you're not going
Man I wanted that boat.I was on it like a pot a neckbones. A
Neglect it and Big Bill is going to knock
JavaScript is disabled. pressure exceeds the blower pressure. If you do not see the 71 Series part you are looking for, please use . Fuel Burn, Engine Life, Service, Part Availability, Ect, Ect. Thats all the longer the engine would last! Articles, Images: Copyright 1997 - 2018 David H. Pascoe All rights reserved. If this is your first visit, be sure to
2300 rpm 2300
A good deal at 735 hp and below. the power output, the more critical maintenance becomes. Probably the most outstanding feature of the DD
Stock# 12.7L-06R0131749. they make some good ones, and occasionally some not-so-good ones. The numerals 6 and 71 stand for the number of cylinders in line (6V designates a V-6, which appeared in 1957) and the displacement of one cylinder in cubic inches (actually 70.93 cubic inches). Are you expecting 30kts? The exhaust valves close, and the piston ascends for another compression stroke. Another effect is that the higher
When money is not the issue, by all means play
a lot of propellering problems. Marine Engine Rated Horsepower (SHP) with N55 injectors: 100 at 1000 RPM, 121 AT 1200 RPM, 140 at 1400 RPM, 158 at 1600 RPM, 172 at 1800 RPM. you might take a pair of 500 hp 6V92s over a pair of 400
displacement 6-V92 is ONE THIRD physically larger than the Cat. as well as being under pressure. because the blower can only blow so much air. The Integrated Detroit Powertrain combines our most fuel efficient engines ever, the GHG17 DD13 and DD15 , with the technologically advanced DT12 transmission and Detroit tandem high speed ratio tandem axles to help you get the most out of every gallon of fuel.. With engine technology calibrated to deliver greater . Someone else will have to tell cruise and fuel consumption. beyond what I would have thought they could get away with. This hasnt happened, and its a good thing, too. Notice that it's displacement is is 636 cu. Compare the specs of this Cummins engine with
Created Date: 4/14/2006 1:26:31 PM The blower and turbocharger aspiration system constitutes
for speed," and everyone wants to go fast. 580 bhp, Crankshaft power (high output) 399 kW
cons depending on the application of the engine. The 6-71 is a two-stroke engine. If the sixth digit is a 2, then your engine is a natural, or non-turbo engine. 6V71 Detroit Diesel Engine Torque and Horsepower
The four cycle engine
If you
get a handle on longevity. You may also visit the Boat Motor Manuals section of our site to obtain a service manual. range, and do fairly well at pushing larger boats that have flatter
Join Date: Sep 2009. Detroit 6V71 Parts and Information Usually its one injector that sticks and it holds the rack wide open. I've been around these engines since the late 1950s. 3000 hrs on them. Myth #3: Diesels are more economical. The inline model was first introduced in 1938 and the V configuration came later in 1957. 2011 Sam's Marine. could see a 3208 and 6V92 sitting together side-by-side on the floor,
The same basic design was used for more than sixty years. fuel to the injector which, in a four cycle engine is nothing more
And it also greatly reduces the internal
Diesel Parts Direct sells new and remanufactured Detroit Diesel parts. 635 hp, Crankshaft power (intermittent) 433 kW
on, the owner starts fooling around with exotic propellers trying
from Buying a Boat, "What
in his family who began his surveying career at age
"Adjusting the rack" is how you tune a
horsepowers. Such is life in the fast
is no different than the human body. These are moderate weight engines with as low
A diesel has no spark plugs. The other little Cats? Now were back to square one with the Cat
Because it was never designed to dissipate those kind of heat
Particularly the conversion
because of the interchangeability. In performance, the 6-71 will compare favorably to the DT466 in everything except for fuel economy. The operating system of the two cycle is radically
comes up and starts compressing the atomized fuel, it is going to
Yachting may receive financial compensation for products purchased through this site. Fuel manifolds, which are cast internally within the cylinder head. Theres just no getting away from the fact
in tip top shape is of extreme importance to your engines
This interchangeability also has a tremendous effect on parts
If a rough idea is all you're looking for, 8 to 10 gallons. And one more thing. Introduced in 1938, production ran until 1995. Long story short, it is ridiculous for this vessel to have 735HP engines (as it can't plane). Thus: at continuous full power (116 kW @ 2100 rpm) it will use approx 25.0 liters per hour. The modern diesel is very sophisticated, complex,
They run great, I run them at 1950 RPM. Posts: 6,194. typically another 400-600 lbs depending on engine size. of Marine Surveyors in 1972, he has conducted over
Published by: D. H. Pascoe & Co., Inc. In addition to the boat repair forum we also offer OUTBOARD PARTS, INBOARD PARTS, STERNDRIVE PARTS, REPAIR MANUALS and BOAT ACCESSORIES. We carry a huge selection of parts for the 6V71 Detroit Diesel and the 6V71 Turbo Detroit Diesel. pros and cons. compare engine weights. Using a pair of 425 hp
You can probably appreciate that if the cylinder
125x147 mm 4.92x5.79 in, Displacement
On average, an in-tune four-stroke gasoline engine will burn about 0.50 pounds of fuel per hour for each unit of horsepower. going to explain in detail why this is a difficult question to answer,
a degree in higher education, particularly engineering and naval
They sell a lot of parts, and
that big diesels are too expensive to fool around with. stick it to you good. Well, simply
A Bonnier LLC Company. 1. Who is Katy mixon body double eastbound and down season 1 finale? Because the turbo gets hot, it
year old 3116 engine yesterday. different than the four cycle, which operates more like an ordinary
That figure does not include the engines made for Gray Marine. before it begins to break down. 2250 rpm is as fast as I run, burning 24 gals. 0.39 to 0.41 gallons/horsepower/hour depending on horsepower demanded. will get either too much or too little fuel and the owner wont
8 knots! In both types of two-stroke engines, every compression stroke results in a power stroke, causing a diesel spinning at 2000 rpm to sound as though it were turning 4000. 6V71 Detroit Diesel Specs and General Info
TIA Don. Maybe someone will see this. Detroit Diesel employed a gear-driven Roots supercharger a positive-displacement lobe pump known for its approximately 90 percent efficiency at low rpm. . are very complex and expensive to replace if one gets damaged, such
large increase in power, which is why they do it. of gas to diesel. Insurance and Issues of Law. more refined. Weight is 32,000 lbs. Plus it runs 500 rpm faster. Is that possible??? As with Mercedes (to
The 6-71 helped win the Second World War powering tanks, trucks, landing craft, generators, road-building equipment and anything else soldiers could press it into service for, earning the admiration of many veterans. Today we have a "need
After the compression stroke, the piston travels
It's been much the same for Detroit. Well, another year has gone
Each cam shaft has three lobes per cylinder. As mentioned, there are thousands of these still in use throughout the world and good parts availability. for more potential trouble, but also increase efficiency considerably. We also have gone through each engine type, and arrangement, so the parts that you see on a given page, will be the parts that fit your engine. Of course, that is an utterly useless
has to throttle up to a higher RPM before a similar amount of power
Caterpillar DD engines tend to be large
the later by both Cummins and Caterpillar and virtually all the
due to the long stroke, complex engine block and more components. Website built by: Relivo Media
up on the top of the old time drag racers made famous by the likes
Copyright 2019 Diesel Pro Power, Inc. 760 NW 4th. and uses the rushing hot exhaust gasses to turn it. Been Lookin At A Few 44ocean's With The 485hp 6-71tib Engines And Wanted To Know What To Expect. Un, uh. Thanks for jogging my memory. Quoted the fuel consumption of his Roamer 56 as. they do not like to run hot, that is the major reason these engines need to be rebuilt. This instrument greatly increases the pressure in the air box compared to non-turbocharged engines. engine castings (by yesteryear's standards). Torque (Lb Ft) with N55 injectors: 550 at 800 RPM, 540 at 1600 RPM, 510 at 2000 RPM. I personally l Iike the exhaust note - sounds something like a turbine. will fly to pieces at 435 hp with a minor cooling system problem. The inline models were offered in a one, two, three, four and six cylinder variants. appraisal. Thus, the DD has not only water jackets, but air galleries cast
by roller followers placed in the head with a very short "pushrod." you now have a bigger, heavier engine running at a higher speed
double the number of internal parts as say a Caterpillar V-8, making
premium in weight and the space to mount it in. negates the virtues of those engines from a by-gone era. For boats at 20k lbs and above, pushing those weights
Except for sailboat auxiliaries, you wont
The problem with diesels, you see, is that unless
and no blower. 8.5-10 gallonsp er hour at 19-22mph. Other significant differences include the large
I recently purchased a 40ft ex seiner with a 200hp rated 6-71 Detroit diesel the boat weighs 18tons beam of 12'7" and draft of 6'6" what sort of fuel consumption can I expect? Two cycle and four cycle engines each have their
Problem is, that turbo air is hotter,
I rebuilt a couple back in the day, every part that wiggled was worn completely out. In terms of overall reliability, Id rate them about the same
parameters that questioners are capable of defining. acute loss of power and other serious problems. hundreds of boating accident investigations, including
more air to the blower, thereby increasing the speed and completeness
Coolant capacity is 7.5 gallons. MTU Detroit Diesel, a Tognum Group subsidiary, opened a new Gulf Coast Sales and Operations center in St. Rose, Louisiana, dedicated to the growth of engine sales in the commercial marine industry. life. because the available choices are so few. This is the large housing you find on the back of the engine and
reputation was based up very unsophisticated, slow turning, low
engine. valves and a blower, compared with a four cycle with only two valves
Every little deficiency becomes a major fault. The 6-71's siren song at full chat seduced generations of yachtsmen. Ergo, when youre intercooler gets dirty,
For a better experience, please enable JavaScript in your browser before proceeding. Tuned for commercial duty, it produced 165 horsepower. 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. No where near 300HP, let alone 400 plus. They were rebuild with 800 hours on them, they had bad risers, I now have 2200 hours on them witout any problems. four cycle. Sep 20, 2017. Reply Like 10-19-2009, 11:09 AM # 2 jjexpress Junior Member Thread Starter Join Date: Aug 2009 Posts: 22 Likes: 0 Received 0 Likes on 0 Posts