Detroit Diesel 8.2T

[Highliner]

I am currently looking to purchase a 1986 Ocean Alexander 44 which is in exceptional shape and a fair price. The engines are Detroit Diesel 8.2T’s and I have read some unfavorable articles about them. Anyone running these engines or have experience with them?

 

[Rufus]

I am currently looking to purchase a 1986 Ocean Alexander 44 which is in exceptional shape and a fair price. The engines are Detroit Diesel 8.2T’s and I have read some unfavorable articles about them. Anyone running these engines or have experience with them?

We have a pair of them in an '89 440. Owned since2005. Just over 1500 hours. They start instantly, don't leak oil and are very fuel efficient. I don't run them hard... 1500-1600 rpm (hull speed plus range) unless the sea state demands a higher speed. I pulled the engine and transmission heat exchangers for a good cleaning about ten years ago. Other than filters and belts, that's it. They like Rotella T-6 oil...better oil control than regular dyno...seems to better tolerate the low speed running with light turbo boost .

There's lots of negative dock talk about these engines....mostly from people who've never owned them. Yes,if you run them hard...or if the previous owners ran them hard, a head gasket issue can pop up. Which reminds me...you need to check that the engines have been retrofitted with the larger head bolts, which went a long way toward mitigating blown head gaskets. But try running any of these older engines on the pins and they will have issues...try it with the old Lehmans...on second thought don't.

Anyway, take a look in the archives. Actual owners like them and had no significant issues. Then look at Cats, Volvos and Lehmans....plenty of problems. The bad rap came from truck applications where they were disliked by maintenance personnel because of the injection rack, which required a lot of maintenance because it was always in motion on a street vehicle. On a boat...it's set it and forget it for the most part.

Run them at trawler speeds and they will last forever. Just don't let them overheat. More than a few engines had early problems with faulty thermostats. OA installed overheat alarms to save head gaskets. Make sure this boat has them...or install alarm sensors on the exhaust exits...or both.

I believed the stupid dock talk and actually bought a spare engine and transmission. It's been sitting on the shelf in my garage for sixteen years. Survey the engines. Check that they start quickly...don't worry about it.

Two other things...

1. The crank case ventilation is an open tube off one of the valve covers...the exit is at the turbo intake. When run at high power, the suction at the turbo will pull excessive mist out of the valve train area and it will drip down the back of the engine. Looks like a leak around the oil pan or crank seals. It's typically not. A closed vent system can be installed, but not an issue unless the engines are run hard. New turbos are available on Ebay if that's a concern.

2. New turbos are available...Ebay...in the $1K range.

PM me if you want to discuss. Back in 2005 I actually spoke with the Johnson and Towers engineer who headed up their marinization project for DD.

 

[Highliner]

Wow, thanks Rufus, you have given me hope. It’s a tough market to find a good boat in and I was really happy when I found this one. However after I read this article I had almost given up hope on this boat.
https://everythingaboutboats.org/detroit-diesel-8-2/
If the buyer accepts my offer I’ll have a through inspection by a qualified marine diesel mechanic and make sure that they have the larger head bolts, overheat arm sensors and… if I ever need a replacement engine, I know where to find one.
Thanks for the PM offer, if the seller accepts my offer and the mechanic says that they are ok, I’ll might need some advice down the road.
So how are you liking your OA after 16 years?

 

[DryDoc]

Though not a DD owner, I can echo what Rufus had to say.

There is a 1990 Canoe Cove, with twin 8.2s in our family, which has had been in the same hands, since 1994. In 22 of those 27 years of ownership, that boat has spent from 3 to 5 months, cruising between the south coast of BC and SE AK.

When she tucks in behind Mound Island next year, she will have just logged 5,000 hours.

With the exception of specialized, routine work on items like turbos and heat exchangers, almost all maintenance has been carried out by the owner, with the periodic assistance and over sight of Canoe Cove’s former 8.2 specialist, now retired.

This year (2021) is the first time any part has been difficult to come by; a hose which Cat has a close and workable replacement for.

Keys to long life are; a spotless inviting engine space, meticulous routine maintenance, gentle running and an 8.2 mechanic who grew up with and specializes in these engines. That last one is becoming harder to find than parts.

I would accept 8.2s tomorrow, if they surveyed well by an 8.2 specialist and had a very detailed, verifiable maintenance log.

 

[ranger58sb]

The one we had in a 34' '87 Mainship III worked fine.

There are SEVERAL threads about those around here; you might review those for broader insight.

-Chris

 

[Ken E.]

Boatdiesel.com also has a lot of info on this engine in its archives. As an aside, I have two friends who have these engines, single and twin installations. Both of them like the 8.2 and have had them 10+ years.

 

[Highliner]

These engines are approaching 4000 hours so we’ll need to find a good DD diesel mechanic. The boat is in Anacordes Washington. Anyone know a great DD mechanic in Anacordes?

 

[Sailor of Fortune]

I had 2 of them... never again!..Keep in mind, these havent been made for 30 years or so. Parts were getting hard to find in the early 90's...Do you think they are going to stock parts for these engines forever? Why do you think DD stopped making them after about an 8 year run?

Call around and try to find your mechanic to work on them and survey them before you consider purchase....Ask about parts availability from DD dealer. Don't take our word for this, ask the experts

 

[Sailor of Fortune]

https://everythingaboutboats.org/ a good read for those considering an 8.2 purchase. do the search for 8.2T "Fuel Pincher"

 

[Rufus]

Why do you think DD stopped making them after about an 8 year run?

They were always intended as an interim four stroke stopgap offering until the new Series 60 came along. That's why. How about telling us about the application where you had all these issues. And what exactly were those issues? I will say there were a fair number of head gasket failures on the 300 HP after cooled version used in small sport fish boats where owners ran them on the pins.

 

[Rufus]

So how are you liking your OA after 16 years?

Spectacular boats. We live aboard 4-5months on Great Lakes. Ideal cabin layout if you don't mind negotiating stairs. Without question the best use of space on a boat this size. You will love the cockpit and sundeck.

Ours had seal leaks around the windshield glass, which I fixed myself. A few spots of discolored teak paneling were repaired with faux paint. Let's see....the paint/gelcoat on the diamond pattern non-skid on the bow started to erode, and the bluish substrate began to show through the white. I repaired that with Interlux Perfection(Snow white)....looks absolutely new. The other cosmetic issue was the paint deterioration of all the black metal window frames. Sanded, masked, treated with aluminum etch primer, masked and sprayed while at anchor with catalyzed urethane semi gloss (Eastwood hotrod satin black). Huge masking job, but turned out well. There are threads in the archives on all of this. OA in Seattle carries things like glass seals and door rollers....the advantage of buying a boat where the parent company is still in business.

My wife and I did a planned epoxy barrier coat shortly after we bought it (look for evidence of blisters during your survey. Not a structural issue, but cosmetic. Pulled the shafts and did all the cutless bearings (three on each shaft) plus the stuffing box boots. Balanced props at the same haul out. Replaced the venturi with new UV treated Lexan. Redid the entire black water plumbing with hard schedule 40 PVC. All faucets replaced. Shower sump pumps replaced.

I'm telling you all this as a heads up for what to look for. PM me for other pissant items.

 

[Highliner]

Rufus, thanks for all the advice, it will be very helpful to me as we work through the surveys. Fortunately the boat has been in a covered slip for years so the topsides, window trim etc. still sparkle. Everything looks to have been very well maintained. In our price range (90k to 150) it is, by far, the cleanest, most complete boat I’ve seen and I’m hoping that the mechanical survey does not find any issues which will blow up the deal. Like you, my wife and I will be spending May thru September living on the hook in the San Juan’s, Gulf Islands, Desolation Sound and possibly up to Alaska. I’d be very proud to be an Ocean Alexander owner so I hope it works out.

 

[Rufus]

It just occurred to me that an '86 44' is probably a traditional trunk cabin configuration, right? If so, different animal from our 440...different hull, etc.. But the remarks about the engines are certainly still valid....

One other thing, most DD mechanics are from 2 stroke background. The only thing in common with the 8.2 is obviously the injection system...

 

[Highliner]

Rufus,
Actually it’s a 1988. Forward v-berth, down galley with dinette to starboard, steering station starboard with nice salon. Downstairs aft to owners stateroom with walk around queen bed. Up 5 stairs from the salon to a nice sun deck and up 3 stairs to a really nice bridge. It has a pretty nice cockpit too below the sun deck.
Is that your layout?

 

[Rufus]

Yes, same boat.... If you buy it, I have the prop charts for those engines and some speed/power/fuel burn curves. Let me know.

 

[Sailor of Fortune]

It just occurred to me that an '86 44' is probably a traditional trunk cabin configuration, right? If so, different animal from our 440...different hull, etc.. But the remarks about the engines are certainly still valid....

One other thing, most DD mechanics are from 2 stroke background. The only thing in common with the 8.2 is obviously the injection system...

You have 1500 hours on a 35 year old boat...44 hrs per year avg. My 8.2T had 900 hrs when I got them. I did the headbolt upgrade before putting it in service but I put 800 hrs per year on it at less than the rated RPMs authorized as per the manual. I think I ran it at 2600 or so. Planing hull. Your 1300-1400 rpm/44 hrs per year is hardly a test of any industrial diesel... Why did DD make 100,000 spare engines to replace in warranty engines? They only had 200,000 inservice engines...

 

[Lepke]

Remember most of the problems in these engines happened in over the road big trucks. Where cooling isn't as good and the engines are using most of their hp and at higher rpm than marine engines usually run at.

 

[sunchaser]

These engines are approaching 4000 hours so we’ll need to find a good DD diesel mechanic. The boat is in Anacordes Washington. Anyone know a great DD mechanic in Anacordes?

North Harbor Diesel is worth a call. The last two paragraphs of post #4 are well stated, for any diesel actually.

 

[FF]

From what I understand these engines do fine at low load.

A displacement cruiser should do fie.

However if 180+ HP is required for long term cruising there not the best choice.