useitagainmarine
New member
I was recently talking to family members that are commercial fishermen in Alaska and they were telling me that a few of their fellow fisherman were re-installing the 671NA in retro fit projects.
Many fisherman converted out of the Detroit Diesels over the years mostly to improve fuel consumption and lessen the noise. I had a singe 671DD myself in a commercial boat many years ago.
In the above case these two fisherman had boats(approx. 45 feet) built in the early 90's with two large Man diesel, go fast boats. Well the go fast boats spend most of time going slow when the fuel cost got to $4.00 per gallon.
The engines were needing worked so the cost of rebuilds of the Man's was huge and the cost of installing a couple of rebuilt DD671's were much cheaper. The boats were built with the engines in the stern so the noise was not issue and the boats are only used for about a 120 days a year and sit the rest.
You can buy parts for them anywhere, they are easy to fix, they can use lower grade fuel than newer engines(they will smoke like heck). I once got in on 5 cylinders when a injector froze up, just disconnected the throttle arm from that injector and head home.
Last time I checked you still could buy a starter for the 671 for about $600.00 when the Volvo diesel my friend had cost $1200.00 or more.
We understand that retro fitting a existing boat with DD's two cycles is legal but not for a new build.
Many fisherman converted out of the Detroit Diesels over the years mostly to improve fuel consumption and lessen the noise. I had a singe 671DD myself in a commercial boat many years ago.
In the above case these two fisherman had boats(approx. 45 feet) built in the early 90's with two large Man diesel, go fast boats. Well the go fast boats spend most of time going slow when the fuel cost got to $4.00 per gallon.
The engines were needing worked so the cost of rebuilds of the Man's was huge and the cost of installing a couple of rebuilt DD671's were much cheaper. The boats were built with the engines in the stern so the noise was not issue and the boats are only used for about a 120 days a year and sit the rest.
You can buy parts for them anywhere, they are easy to fix, they can use lower grade fuel than newer engines(they will smoke like heck). I once got in on 5 cylinders when a injector froze up, just disconnected the throttle arm from that injector and head home.
Last time I checked you still could buy a starter for the 671 for about $600.00 when the Volvo diesel my friend had cost $1200.00 or more.
We understand that retro fitting a existing boat with DD's two cycles is legal but not for a new build.
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