Atomic Four .......Could You?

[smaarch]

Beta Marine makes a drop in replacement for the Atomic 4
Atomic Four Replacement - Beta Marine diesel engine using high performance Kubota diesel, Atomic Four, atomic 4, repowering

if i remember the cost is somewhere around 5-6 boat units for the engine and yes there will be other expenses....
Really depends what the OP is trying to do with his boat. The A4 is a great little engine for the right purpose. (not withstanding the (scratch my head) problem i am trying to currently solve.

all things being equal: a sailboat repowered with a diesel may fetch a bit more money on resale - i doubt you would recoup the investment...so it's sort of a wash....

Originally Posted by roverhi

The big negative with an Atomic 4 is resaie. The same questions you are asking about the A4 are the ones potential buyers for your boat will ask when you are ready to sell. There has to be enough price differential in an A4 powered boat to make up for that.

Should you decide to reengine the boat with a diesel, cost will run well over 10 boat units to have a yard do it. That doesn't mean that an A4 engined boat is worth that much less than a diesel powered boat but it is a significant factor in a boat's value. If re-engining is in the future it's way cheaper to buy a Moyer rebuilt A4 than having a diesel put in. Actually, probably way cheaper to put in a used A4. Have seen seen supposedly excellent conditions ones advertised at $2,000 or less.

It's not just the cost of the engine but changes to the mounting system, filters, and possibly the fuel tank that jack the price up of a diesel conversion. Believe the Universal A4 'drop in' replacement is no longer available. Know first hand that Yanmar doesn't have a drop in replacement. Are there engines out there that don't require major rework of the engine bed or relocation of the engine to replace an A4?? The mounts are not the only possible difference. Diesels are taller than the A4 and that could also be an issue on some boats. Anyway, if you are thinking of buying an A4 engined boat and then re-engining it with a diesel, it better be priced to reflect the steep cost.

[S/V Alchemy]

Since the market for under-35 footers went south about 10 years ago, I can't think of a single Good Old Boat (by definition older than 1984 or so which was when the Atomic 4 ceased to be made) for which a diesel repower would make any kind of economic sense in terms of resale value.

If you had a duff A4, were 40 years old and wanted to switch that 34 footer from daysailing to "light offshore" or "extended coastal motorsailing", in the context of a 20 year ownership of the same well-maintained boat, yes, I would consider dropping in the Beta replacement, retanking, reshafting and repropping, and would think myself lucky and able to do 90% of my own labour if I got away under $12K.

You can get some nice, entire, working and plaid-cushioned, freshwater-only boats from the '70s-'80s in that size range for $12K these days.

I base my opinion on an ongoing but nearly finished complete replacement of a 1988 Westerbeke 52HP with a new Beta 60 in a larger boat. It has made sense to do so and has come in more or less at budget, but it's neither been fast nor cheap; swapping out an A4 wouldn't be, either.

[um saudade]

I think a big part of the issue is not being addressed here: The owner/operator part.

I don’t think my experiences in life are all that unique in a couple of respects; we all know people who are pretty competent at most things and then, on the other end of the scale are the guys who can’t seem to understand anything of a mechanical nature.

Now to my way of thinking, if I was totally inept, I would not venture out on a big ocean with a small boat but yet I have seen it time and again. The big issue comes when the guy who can’t sail, can’t fix anything and can’t navigate without an LED screen in his face actually completes a successful passage. Now he takes ineptitude to a higher level and becomes an expert sailor for he has proved his mettle in his opinion, but that is another story.

So in picking an engine the criteria of the owner must be honestly measured. If you can tinker and keep things running then the little A-4 is pretty much a non-issue when it comes to having one power a smaller sailboat. If you don’t feel a good level of comfort with a little occasional tinkering then it is certainly not for you. I don’t think you need to learn mechanics on the engine in your boat either. You must bring some good practical experience to the table for if you try to learn the basics on your boat engine you may well end up costing yourself far more than just money.

If you have vague ideas of how an engine operates then stick to something very new and clean, pay someone to maintain it and hope for the best. I find these are the guys who agonize over the choice of oil for their engines for it is perhaps the only thing they feel they have any control over.

Everybody carries gasoline so some gas in a tank is no big deal. If you are so afraid of fumes sending your boat up in a fireball then install a fume detector. The human nose is the best fume detector of all and you should be able to smell gasoline or propane at levels far below the fume detector, let alone an explosive level.

[rubyjean]

Originally Posted by um saudade

I think a big part of the issue is not being addressed here: The owner/operator part.

I don’t think my experiences in life are all that unique in a couple of respects; we all know people who are pretty competent at most things and then, on the other end of the scale are the guys who can’t seem to understand anything of a mechanical nature.

Now to my way of thinking, if I was totally inept, I would not venture out on a big ocean with a small boat but yet I have seen it time and again. The big issue comes when the guy who can’t sail, can’t fix anything and can’t navigate without an LED screen in his face actually completes a successful passage. Now he takes ineptitude to a higher level and becomes an expert sailor for he has proved his mettle in his opinion, but that is another story.

So in picking an engine the criteria of the owner must be honestly measured. If you can tinker and keep things running then the little A-4 is pretty much a non-issue when it comes to having one power a smaller sailboat. If you don’t feel a good level of comfort with a little occasional tinkering then it is certainly not for you. I don’t think you need to learn mechanics on the engine in your boat either. You must bring some good practical experience to the table for if you try to learn the basics on your boat engine you may well end up costing yourself far more than just money.

If you have vague ideas of how an engine operates then stick to something very new and clean, pay someone to maintain it and hope for the best. I find these are the guys who agonize over the choice of oil for their engines for it is perhaps the only thing they feel they have any control over.

Everybody carries gasoline so some gas in a tank is no big deal. If you are so afraid of fumes sending your boat up in a fireball then install a fume detector. The human nose is the best fume detector of all and you should be able to smell gasoline or propane at levels far below the fume detector, let alone an explosive level.

Well Said...............Michael.......

[Bash]

Originally Posted by um saudade

If you have vague ideas of how an engine operates then stick to something very new and clean, pay someone to maintain it and hope for the best. I find these are the guys who agonize over the choice of oil for their engines for it is perhaps the only thing they feel they have any control over.

In other words, real men don't mind Atomic 4s?

As someone who wouldn't own a boat with an Atomic 4, I'll take the bait.

If I'd somehow convinced myself not to be concerned about the issues of reliability and safety, I still wouldn't want a gas engine on a sailboat. I live in an area where all gasoline contain ethanol, and the shelf life on that is only a couple of months in the marine environment. In my car I know I'll go through a tank of gas before it goes bad, but the same can't be said for my boat. Last year I didn't go through a full tank of diesel the entire year.

No thanks. An Atomic 4 would be a deal-breaker for me.

[ElGatoGordo]

Instead of "mine's bigger than yours" , maybe we could just agree the A4 works well for many thousands of people, but maybe not for everyone.

[rubyjean]

As for me, I worry more about propane way more than gasoline. I alway's have gas for my outboard & generator on board. I always keep propane mounted off the stern pushpit. Not every one can afford or want a 50' boat, I've alway's preferred under 30'. I've crossed the so. Indian Ocean w/ a 27' boat in 83-84 cruise. Yes it was a tough 46 day's..... Michael..

[Dockhead]

Originally Posted by nimblemotors

Because most of them are running at 8,000 rpm all day long,
and are making about 30 times as much horsepower.

This is impossible for a diesel. But just becaues they are vastly superior here does not mean they do not work at lower rpm.

Not really. My snowmobile engine redlines at 8000, and cruise speed is about 5000. They are much slower turning than four strokes and much torquier. The equivalent Yamaha four stroke redlines at 13,000 or thereabouts.

My snowmobile engine makes 120 horsepower out of 600cc. Contrast to my boat engine which makes 100 horsepower out of 2000cc, and that with a turbocharger and intercooler.

I think a specifically designed marine two stroke petrol engine could be good. Downside would be -- as with two-stroke outboards -- would be fuel efficiency if they are not direct injected. A direct injected two-stroke would be very interesting.