Detroit 2 stroke pros and cons

[Carpediem44DB]

I am in search of our next boat which will likely be 55 to 60 foot live-a-board boat of the quality and design capable to comfortably cruise the west coast from Mexico to Alaska for the next ten to fifteen years. There are a handful of boats that we are considering and one of the biggest concerns other than basic cabin layout is the power plants. I really like the Cummins engines with the exception of the 480CE and I have heard of a few engines to 'stay away from'. I am interested in the experience anyone here might have with the Detroit 8V92 series two strokes as opposed to the MTU series. Any thoughts would be helpful in narrowing our search.
Thanks

 

[CaptRonn]

The Detroits are extremely reliable (when maintained) and the parts are readily available. Yes, it's old technology, but it works. Another bonus is they can be overhauled in frame.

 

[bahamabreisus]

We are probably close to 3000 hours. Ours are not the DDEC version. No issues in 16 years of ownership. Only real complaint is noisy. DDECs started in 97-98 I think.

 

[FootballFan]

I am really a fan of the MTU's.

Only larger cummins I would consider would be QSM. Not going back to a QSC.

 

[Gofirstclass]

CD, I know where there's a nice 550 Sedan Bridge with Cat 3406C's that is going on the market this month. PM me if you have any interest.

 

[Carpediem44DB]

CD, I know where there's a nice 550 Sedan Bridge with Cat 3406C's that is going on the market this month. PM me if you have any interest.

I see your 550 on yacht world. We are determined to stay in the 2000 year models and above. Been spoiled owning the 06 44. Looking at a 2002 56 Navigator Rival. Now I just need to get the true skinny on the Volvos!
Good luck on the sale, I just listed Carpe Diem again to see just how hot this market really is. All my broker buddies say that they are out of listings.
Carpe Diem

 

[RollerCoastr]

We are determined to stay in the 2000 year models and above.

That was about the end of the run for 2 stroke Detroits.

 

[Henry Boyd]

In our search for a new boat we looked at an older Sabre that had V8 Detroits. We got serious about the boat and got copies of the service records and discovered a recent invoice for the fabrication of a water jacketed exhaust manifold. I spoke to the shop that did the work. The story as related by the shop was that Detroit apparently sub contracted the marinization of their engines to a number of different vendors. Apparently the sub contractors were free to follow their own designs. That in turn has lead to some parts being hard to find.

 

[Skybolt]

If you do go older then 2000 ...

I have had Detroits for some time now, my father taught me what he knew back in the day. I do all of my own work except adjusting the rack. Every Detroit mechanic I have knew/spoken with really like the 6/8v92 series and say they are work horses. I have seen the same thing. The key is NOT to get the DDEC engines and not to go over the 1:1 ratio of horse power to cubic inches. Also read up on them over at boatdiesel. There are plenty of them still going and parts are easy to get. Most of the 92 series were put together by Stewart & Stevens. They are still in business.

The only advice I can tell you on the 92 series is replace all of the oil line's and both turbos if the exhaust coupler looks even a little rusty. They have a habit of breaking off without any sign of being bad. They rust out from the inside out. The engine/transmission oil lines tend to collapse on the inside, they can pocket the oil very quickly. Unless they were already replaced with the wire lines., they seem to hold up pretty well.

I am very, very jealous of what you are doing, I can't get my wife onboard with that. Nothing like living aboard a beautiful older boat. Best of luck on your decision.

 

[mquiet]

Great engines with exception of DDEC. The digital control pushes the envelope too much and the parts are super expensive. My Detroit guy told me to run from the DDEC. Don't walk.....run.

 

[Almightys]

I’ve been told to keep up with coolant changes and don’t let them overheat ( not like any motor likes that right)

 

[Skybolt]

I’ve been told to keep up with coolant changes and don’t let them overheat ( not like any motor likes that right)

Exactly! There toast @205 degrees. Wet liners have rubber seals top and bottom of each cylinder. Just run Detroit anti-freeze or fleet charge for cumings and add pencool 2000.