What a fun project. A metal boat, a single electronic Tier 3/4 engine, redundancy and lightning may open the door for debating a small diesel get home. Dashew’s popular FPB 64 line went through similar thinking, with a get home retrofitted on early models and standard thereafter.
What engine has been selected?
It is indeed great fun Sunchaser and thanks for your interest and questions.
We decided to go very "old school" with our single main engine and will be installing a Gardner 6LXB once the hull is done. As Christine mentioned above I will be posting more in depth articles on this in the near future on our
Mobius.World blog and in the interim if you’re curious you can read some of what’s behind this decision in my post last month
“Mr. Geeeeeeee is in the House!”
The wording in your question is part of what led us to this decision: Tier 3 / 4 and lightning. We had indeed been looking at a Tier 3/4 engine, most likely a JD6068 but several hours into an in depth meetings with the JD folks they informed us that there are several key parts which they are not permitted to sell us in advance for spares and this includes the ECU!
Apparently the only way allowed is to send them the failed unit and they take the log data out of it, reprogram the new one to pick up where the old one left off and send it to us. A perfectly workable situation for most people perhaps but not us. What do we do when lightning strikes, literally or figuratively??
We purposely spend most of our time in the most remote locations around the word we can find and they are usually hundreds if not thousands of miles away from most civilisations so having parts sent in and out is just not workable for us. The other characteristic of the modern engines, Tier 4 in particular is the added need to burn DEF along with the diesel. Given our very large fuel capacity (14k litres) we would had to add a DEF tank or two which was doable but we have no confidence that we’d be able to find DEF in the many parts of the world we cruise in. So for us and our certainly unique use case, a new diesel engine is not a good fit whereas the Gardner fits us like a glove.
I will also post more in the future on our decision to go with a single engine setup and no wing engine but short story is that we feel most comfortable going with a single main engine with a very low probability of failing us and if/when it does that I can fix it and get us going again without any outside parts or help. We have done the same on all our previous boats and we carry a very full compliment of spare parts and a particularly well equipped set of tools and machines in the workshop. This combination has worked well for us for over 100k nautical miles so far and we think we are upping our game in terms of reliability with the Gardner and with an even more well equipped set of tools and machine shop onboard.
I’m currently restoring the Gardner to factory new condition as pretty much all parts other than the major castings and crankshaft are still being made and we have every one of them on hand already. I will cover this restoration and installation further on the
Mobius.World blog so you can follow along there as you wish.
Wing engines don’t make sense to us in a new build as you would go with twins instead. But after a LOT of consideration of ALL the propulsion possibilities we kept coming back to a super reliable and well maintained single engine as the best choice for us. We appreciate that this is not what most others would chose but this isn’t their boat and we’re going with what is just right for us.