Detroit Diesels 8.2 litre FWC

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8.2’s got a bad reputation early on because of issues that got fixed in later manufacture. I had an old Tollycraft 37 with twin 8.2’s that never gave me a bit of trouble. And I never had a problem getting parts.
 
The total number of DD 8.2 owners -- past or present -- here is likely not a representative sample. Individual reporting of success or failure is only anecdotal.

But so far, the number of us who here haven't had an 8.2 failure is apparently exceeding the number who have.

:)

-Chris
 
With any older long out of production engines, or for that matter any major equipment on the boat, before purchasing I call around to try to find parts and service in the area where I expect to require support. 3 yrs ago I purchased a boat with 83 vintage CAT 3208s. They are another engine with a bad rep for failure according to 'expert' sources. I quickly found 3 shops in my area that still support those engines. I also did a bit more digging and learned remans and running take outs can be found though very expensive. I moved ahead with the purchase eyes open to the risk.

I now find 3 yrs in that some parts are becoming hard to find or are very expensive. For now there is some aftermarket support. Shops with experienced techs are still booking work. Such is life with older engines.

I did look at one boat with DD 8.2s. My calls all got the same general response. Don't buy it, you'll have problems finding parts and mechanics familiar with the engines. Not dock talk, advice from real hands on service shops and techs.

Make the calls in your area, assess the risk. Forget the dock talk and anecdotal 'evidence'. Satisfy yourself. If you can trust the engines and their support you may have found a bargain because other potential buyers are shy of purchasing. If you can't trust the engines and their support you'll be 'looking over your shoulder' every hour you are underway.
 
With some engines, the answers you get vary widely depending on the boat you ask about or the people you ask. Simply because the engines may have held up fine in one usage pattern, but were short lived in another. Think about how short-lived some of the high HP Detroits are reputed to be in sport fish usage where they're frequently run quite hard. Yet the same basic engine (possibly at a lower HP rating) in a different application is known to last many times as long.
 
ranger58sb said:
The total number of DD 8.2 owners -- past or present -- here is likely not a representative sample. Individual reporting of success or failure is only anecdotal.

But so far, the number of us who here haven't had an 8.2 failure is apparently exceeding the number who have.

:)

-Chris
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Still a controversial engine..... Meaning resale will suffer in price or time on market.... Hardly a selling point that peeps with no problems outnumber the ones who had issues... Not exactly a strong endorsement for an engine....that hasn't been made in decades, and production stopped after less than about 10 years..
 
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I had one boat with Volvos and when I am shopping for a new boat the first thing I look at is what engines it has. If it has Volvos I move on to the next boat.
 
When we were first boat shopping we looked at an OA with twin Detroits. Spoke to the local go-to mechanic and he said that parts are really hard to come by. Told me a story about someone being laid up for 2-3 months waiting on an after market part from overseas. Gave me an off-the-cuff price of about $50-60k to re-power with new engines. We passed. Our current boat has a single ford lehman.
 
JohnO said:
When we were first boat shopping we looked at an OA with twin Detroits. Spoke to the local go-to mechanic and he said that parts are really hard to come by. Told me a story about someone being laid up for 2-3 months waiting on an after market part from overseas. Gave me an off-the-cuff price of about $50-60k to re-power with new engines. We passed. Our current boat has a single ford lehman.
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I waited 4 weeks for an exhaust manifold...in 1990..... Sold the boat in 1991. Personally I wouldn't want to be trying to find parts for these engines 30 years later... And I had a lot of connections in the marine industry at the time.
 
Rufus said:
Cute. I don't have great "diesel skills", but I do have a brain and maintain and operate these engines where they survive just fine. In usage, I think of them as 120-130 HP Lehmans with a big cushion. I tell every prospective buyer exactly that. (By the way, thanks for sabotaging prospects for selling the boat...rather mean spirited, I'd say)

Which version (NA, early turbo, later turbo) and year of the engine in your truck? What size truck? Why did the first one fail? What was wrong with the second one? We've been in this debate before with no specifics from you. Just opinion...same as the undocumented opinion paper in the link.
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The OP asked for input about these engines and is entitled to all of our thoughts.
You might be responsible for sabotaging prospects for your sale by your response.
There is a wealth of detailed information about these engines available.
To claim that unfavorable details are less relevant than favorable is disingenuous.

Any engine can have 'teething problems' as these did. It is true that they are not
as preferred an engine as some others. It is true that they had a fairly short run.
It is also true that well cared for engines can last indefinitely as yours seem to be.
I would not fear buying your boat with them but would remain vigilant, as you do.
 
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I have twin DD 8.2 normally aspirated Fuel Pinchers as original equipment (true!) in our 1982 Grand Banks. These engines are rated for 165 HP @ 3000 Rpm and 350 lb/ft of torque at 1200 rpm. At our normal eight-knot cruise rpm of 1600-1800 rpm, they are incredibly under-stressed, and burn 6 gph total. As with most marine engines, the greatest danger is from overheating. Well maintained, they have been bulletproof (3600 hours). I understand their bad reputation, but have not experienced it myself.
 
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Detroits will cost 2x compared to a cummings rebuild.

Detroits a 3k hrs life span Cummings generally 10k hrs

Detriots burn 25% MORE fuel than a cummings mechanical , Even more a % more compared to electronic engines

Remember time kills engines. Springs compress. internal sweating causing corrosion. Seals and gasket harden and just fail with time. When you are looking at the old gals, Low hours is not necessarily a good thing.

Repower cost easy 100k to 150k. Buy something that has been repowered.
 
Greg QS said:
Detriots burn 25% MORE fuel than a cummings mechanical , Even more a % more compared to electronic engines
Click to expand...


That's true of the 2 stroke Detroits, but not of the 4 stroke 8.2.
 
KnotYet said:
The OP asked for input about these engines and is entitled to all of our thoughts.
You might be responsible for sabotaging prospects for your sale by your response.
There is a wealth of detailed information about these engines available.
To claim that unfavorable details are less relevant than favorable is disingenuous.

Any engine can have 'teething problems' as these did. It is true that they are not
as preferred an engine as some others. It is true that they had a fairly short run.
It is also true that well cared for engines can last indefinitely as yours seem to be.
I would not fear buying your boat with them but would remain vigilant, as you do.
Click to expand...

If I chased off uninformed dock talkers, that is a good thing.

No, there is not a wealth of documented, cogent failure information on these engines. There is a wealth of disparate, secondhand observations, anecdotes, and opinions. The engine obviously had an overheat/head gasket problem. Detroit introduced a fix. I believe it was effective. But for good measure I reduced the size of the engine operating envelope. Every interested buyer will get the briefing.

I limit maximum engine speed to rpm for 125 HP...14 knots (both engines). That's one half of the rated power and 3 knots under maximum boat speed of 17 knots at the original full power setting...plenty adequate (thank you Ed Monk for the nearly liner power required curve through the "hump" speed range). Normal cruise is 1550 rpm for 8.5 knots. BTW, the OA 440 has an obnoxious factory installed engine water temperature alarm that is set at 205-210 F. If a head gasket fails, it will be from a raw water pump malfunction coupled with an inattentive idiot operator. No different than for any other marine diesel engine.
 
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Rufus said:
If a head gasket fails, it will be from a raw water pump malfunction coupled with an inattentive idiot operator.
Click to expand...

Wait a minute, there are idiot operators?
No one told me that.

Action
 
While I have never owned one of these engines it strikes me that if they are truly a good engine they would have had a much longer production run. When an engine manufacturer kills off an engine after a short run it says something.
 
Comodave said:
While I have never owned one of these engines it strikes me that if they are truly a good engine they would have had a much longer production run. When an engine manufacturer kills off an engine after a short run it says something.
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I think they went out of production because they weren’t well suited for the very different use case of the truck market. I don’t think they were primarily made for the marine market.
 
SeaDogAK said:
I think they went out of production because they weren’t well suited for the very different use case of the truck market. I don’t think they were primarily made for the marine market.
Click to expand...
Neither was the Ford 2715E but it turned out a good marine engine operated at constant rpm.
 
SeaDogAK said:
I think they went out of production because they weren’t well suited for the very different use case of the truck market. I don’t think they were primarily made for the marine market.
Click to expand...

Most engines are not developed for the marine market, it is a fairly small segment of the overall market. But most engines are adapted for marine use. However I still maintain that an engine with such a short manufacture must have some issues because it isn’t cheap to bring an engine to market,
 
Both the Cat 3208 and the DD 8.2 were designed for the truck market. They were both introduced around the same time, Cat '75, dd 8.2 '79. Both had early issues that got fixed. The difference is that you can call any Cat dealer today and they will source parts for you. You can call Detroit but they will tell you they no longer support the engine.

To be fair the Cummins 555 is no longer supported by Cummins.
 
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Greg QS said:
the DD 71 series is an extreamly old tec. Goes back to 1938. Originally got its start in construction equipment , stand by genset , and farm equipment . It really expanded in the war times as it was adapted to a tank engine.
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Yes, but that's not the DD engine series under discussion here.

The 4-stroke 8.2 is significantly different from the earlier 2-strokes.

-Chris
 
DD 2 cycle otherwise known as 4-53, 6-71, 8v-71, 6v-i92, 12-71 and many other iterations is a pre WWII design engine that was extraordinary successful and is still supported today.

The DD 8.2 is a 4 cycle engine introduced in 1979. Approximately 200,000 were made before production ceased in the very early 90’s. It is widely believed that only 100,000 engines were put into operations and the second 100,000 engines were used as warranty replacements.

If I had these engines in my current boat I would just keep on enjoying them. However, if I was shopping for a boat I would not be willing to take on the liability that comes with maintaining a 35 year old engine with next to no aftermarket support. I have the same feelings about the Cummins 555.

I would have no issue taking on a 50 year old DD 6-71 as there is tremendous aftermarket support for that engine.
 
tiltrider1 said:
dd 2 cycle otherwise known as 4-53, 6-71, 8v-71, 6v-i92, 12-71 and many other iterations is a pre wwii design engine that was extraordinary successful and is still supported today.

The dd 8.2 is a 4 cycle engine introduced in 1979. Approximately 200,000 were made before production ceased in the very early 90’s. It is widely believed that only 100,000 engines were put into operations and the second 100,000 engines were used as warranty replacements.

If i had these engines in my current boat i would just keep on enjoying them. However, if i was shopping for a boat i would not be willing to take on the liability that comes with maintaining a 35 year old engine with next to no aftermarket support. I have the same feelings about the cummins 555.

I would have no issue taking on a 50 year old dd 6-71 as there is tremendous aftermarket support for that engine.
Click to expand...

+1 100%.
 
Just run away - the 8.2DD was a disaster and a flawed open deck design.
 
If one goes to boatdiesel.com you'll find quite a group of hands on and dedicated 8.2 owners. Two DD guys that are smarter than all get out are Ron Sparks and MDS. To get into the 8.2 minutiae, details and the archives a $25 cover charge applies.

Several of us on TF follow boatdiesel. I can say for myself anyway it represents the go to marine diesel site, excepting Tony Athens Cummins Seaboard site.
 
sunchaser said:
If one goes to boatdiesel.com you'll find quite a group of hands on and dedicated 8.2 owners. Two DD guys that are smarter than all get out are Ron Sparks and MDS. To get into the 8.2 minutiae, details and the archives a $25 cover charge applies.

Several of us on TF follow boatdiesel. I can say for myself anyway it represents the go to marine diesel site, excepting Tony Athens Cummins Seaboard site.
Click to expand...
This is part of what I consider a 'wealth of detailed information'.
 
I replaced the 8.2s in our boat for some of the reasons stated above but mostly because NO ONE would service them! They were due for a vlave adjustment and I have the magnetic gauge to do it but in a very tight engine compartment barring them over 8 times was not going to happen solo.
It is also almost impossible to source a lot of the parts. Mostly the marine parts but even the thorttle bodies and goveners.
I swapped for two RTO Cummins and they are a joy. I get the same or better fuel economy,faster and they are probably half as loud. They are also easy to service compared to the DDs. My engine rooms seems down right spacious after getting rid of the DDs. That said, the DDs were still running in my boat and had 2,400 hours.
 
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