My reason to consider repowering from the Atomic 4 to a small diesel is twofold..
First in my 40+ years of So Cal boating all of my boats have all been diesel, dependable, easy to work on and safe.
Second, the Atomic 4 has never really been that reliable or run properly. Seems a gas motor in a marine environment is asking for problems.
I guess as I write this the main reason is I am just more comfortable with diesel. I know it does not make a lot of sence to spend the money on an old (1974) boat, but the Columbia is a classic, solid sailing vessel and it seems it would improve the boat with diesel.
It would be a nice upgrade, it's a classic old boat. Hopefully you fill us in on what the options are in rebuilt engines.
You have me thinking, for the same reason I believe used engines are showing up for sale at greater numbers and at much higher prices lately, perhaps there will be a similar growth (my perception), in rebuilt engines. Why not if the demand is there and a shop has the skills? The price would have to be enough of a savings over new to be viable. If you have a drop in option in a re-built engine, that will save significant $$. They would have to come with a guarantee which would mean a reputable source.
I had this rebuild vs new vs used, problem last winter with a transmission needing a rebuild. The transmission, an old style Paragon manual gear that has been obsolete for a long time.
Looking around there were options for used (chancy), rebuilt(less chancy) and new gears(least chancy), as we all know.
No matter what I looked at, unless it was the same unit, the process became more than simply removing what I had, and putting it back on.
A local mechanic knew of a rebuilder in state (Billings Marine). I dropped it off and in a few days got an email that the damage was more than a straight rebuild that they are equipped for, could be done.
In the same email, they had found a rebuilt unit, reduction gear and all, ready to ship. Of course it just bolted on and my obsolete manual linkage snapped on.
The rebuilt unit wasn't cheap, $2500 plus my old core. I needed a new shaft and coupling so total was nearly 4k with no labor on my boat. Had I hired out the job; remove old unit, installed a new transmission -with the related bell housing/adaptor plate, re-figured new linkage and controls, fit the new shaft and coupling, I doubt I would have gotten that done for a lot less than twice what I paid for parts alone.
I'm still with an obsolete transmission. But so is my engine, and come to think of it, my entire 1961 sailboat is beyond obsolete as many added parts since, are obsolete.
The rebuilt transmission performed beyond my expectations. I'm glad to went this route. I'm still obsolete, now by design.
I took a video this season of my obsolete engine I installed over 10 years ago. That used engine - with a history that I trusted - cost $1K. It was installed (my me) in a few hours and very little added $$(a different block-no comparison).
That has turned out well but there is always more of a gamble for used, even rebuilt over new.
