Atomic 4 vs. diesel ?

[dfelsent]

Originally Posted by GusC

I can’t thank you enough for your comments. I am relatively handy, engineer-oriented to an extent, but have no experience working on engines. I am willing and able to learn, but not really excited to having to do it

Just as an FYI. Working on engines, carbureted or injected, gas or diesel, can be lots of fun. Really satisfying too. At least for me.
And generally not hard on the scale of complicated things.

[MicHughV]

I don't know about other countries...but in the USA, gas has a 10% ethanol ratio, pretty much across the board. There are various reasons and claims why this is so.

There has been a push for a 15% ratio, but the pushback from the automotive and trucking manufacturers has been enough to stop it....for the moment.

When the ethanol was first added...there was a rash of engine problems with outboards, a serious problem in many cases requiring new tanks and engine overhaul.

This has been more or less resolved by fitting metal tanks to newer fishing boats, etc, instead of plastic and running metal fuel pipes to all but the last few feet of fuel delivery lines. Most outboard engine manufacturers have a water/fuel separator inside the cowling, but there is also a 99.9% probability there will be a bigger cartridge type water/fuel separator before fuel reaches that engine. The short run of flexible hose is now some or other propriety rubber hose that is not affected by the ethanol.

A few other titbits....most modern outboard engines are now fuel injected, as ethanol laced fuel has a tendency to gum up the inside of a float chamber in a regular carb.

The Atomic 4 is a throw back to the carburetor days. Running today's ethanol fuel in an A4 is almost certainly guaranteed to give you problems. This why most marina's have non-ethanol fuel...but it comes at a price....around $4/gallon. I have seen it priced at around $2.85/gal at some gas stations that do offer it, but filling up 20 five gallon containers to put gas in my boat is not going to work.

It's a pain the arse. I run a fishing boat with twin engines, and filling it up at the marina gas pump causes serious pain to my wallet, but I have other option.

Knowing all this, I would recommend going against the A4. In its heyday, it was a respected engine, but it's a dinasour today.

On top of all that, to carry gas (petrol) inside your boat is a risky business.

There is very little to recommend going with a boat equipped with an A4. Not saying it can't be done, but with so many other options available, there is little sense to pursue this route.

[acem]

I have a Catalina 27 with the atomic (bomb) 4 that has served me well. It requires some maintenance but nothing bad.

Quality Diesel engines are better than gasoline engines in many ways. However not all Diesels are Quality engines. Additionally Diesel engine repair can be very expensive.

The vast majority of recreational boat engines are gasoline.

I would buy another sailboat with an atomic 4 but realize it lowers the value of the boat.

[acem]

How about the allied sea wind they have for sale?

[roverhi]

Every marina I've been to has non alcohol gasoline. May not be universal but boats have gotten a dispensation from the alcohol requirement because of all the problems that the alchohol/gas on older engines. Check before filling up and go elsewhere if they don't have dinosaur gasoline. Have been fueling all my equipment engines with the old stuff ever since I heard of the problems with the drunken fuel. Buy the non alcohol stuff at the marina. Think I've seen other gas stations that have the good old stuff.

Originally Posted by MicHughV

I don't know about other countries...but in the USA, gas has a 10% ethanol ratio, pretty much across the board. There are various reasons and claims why this is so.

There has been a push for a 15% ratio, but the pushback from the automotive and trucking manufacturers has been enough to stop it....for the moment.

When the ethanol was first added...there was a rash of engine problems with outboards, a serious problem in many cases requiring new tanks and engine overhaul.

This has been more or less resolved by fitting metal tanks to newer fishing boats, etc, instead of plastic and running metal fuel pipes to all but the last few feet of fuel delivery lines. Most outboard engine manufacturers have a water/fuel separator inside the cowling, but there is also a 99.9% probability there will be a bigger cartridge type water/fuel separator before fuel reaches that engine. The short run of flexible hose is now some or other propriety rubber hose that is not affected by the ethanol.

A few other titbits....most modern outboard engines are now fuel injected, as ethanol laced fuel has a tendency to gum up the inside of a float chamber in a regular carb.

The Atomic 4 is a throw back to the carburetor days. Running today's ethanol fuel in an A4 is almost certainly guaranteed to give you problems. This why most marina's have non-ethanol fuel...but it comes at a price....around $4/gallon. I have seen it priced at around $2.85/gal at some gas stations that do offer it, but filling up 20 five gallon containers to put gas in my boat is not going to work.

It's a pain the arse. I run a fishing boat with twin engines, and filling it up at the marina gas pump causes serious pain to my wallet, but I have other option.

Knowing all this, I would recommend going against the A4. In its heyday, it was a respected engine, but it's a dinasour today.

On top of all that, to carry gas (petrol) inside your boat is a risky business.

There is very little to recommend going with a boat equipped with an A4. Not saying it can't be done, but with so many other options available, there is little sense to pursue this route.

[mvweebles]

When low Sulphur diesel became mandated back in the 1990s, injector pumps on old Perkins Diesels started wheezing. Many, many were rebuilt. Methanol has bee used in gasoline for a while - if an A4 were allergic, it has been known for a while and fixed. And even if it requires repair, rebuilding a carburetor is a helluva lot easier and less expensive than an injection pump.

As someone else said, not all Diesels are the same. A 1970s era Catalina 30 would have either a A4 gas engine or a Universal 2-cylinder raw water cooled 11hp diesel. Not a Yanmar, not a Perkins, not a tractor-carcass, but an old 2-cylinder raw-water engine. These engines were noisy and will vibrate the fillings out of your teeth. Raw water cooling means they run chronically cool and have endless issues with corrosion. Anyone who out-of-hand extols the virtue of diesel over gas has clearly never owned a Universal 5411.

Not all Diesels are the same. And not all gassers are the same. The A4 was a decently constructed and marinized engine.

Peter

[Jim Cate]

The A4 was a decently constructed and marinized engine.

Your opinion, not mine.

Jim

[mvweebles]

Originally Posted by Jim Cate

Your opinion, not mine.

Jim

Opinion noted. Supporting facts would be nice, but understood its a popular opinion.

To the OP - a decent article on A4s, their strengths, weaknesses, and upgrades that minimize many weaknesses.

https://goodoldboat.com/atomic-4/

Im not advocating for a gas engine, but suggesting that someone in the $5k-$10k market should summarily dismiss one is a bit myopic. My opinion, at least.

Peter

[marshmat]

Originally Posted by Jim Cate

Your opinion, not mine.

Jim

The Atomic Four was a very good engine, for 1949.
But, as others have said, they're outdated, underpowered for anything over about 4 tons, and require frequent maintenance. (All of which was well known by the early '70s, but tradition and inertia are strong in the boatbuilding sector.) We decided to reject them outright when shopping for our current boat.

On the bright side, as a buyer, taking an $8,000 boat with an Atomic 4 and spending $6,000 to repower with a Yanmar or Beta leaves you with a $9,500 boat. So you can let the previous owner take that hit, and buy one that's already been repowered. (The flip side of this is that it rarely makes financial sense to replace, instead of repair, one in your own boat if you plan to sell the boat any time soon.)

I'd be as careful of '60s and '70s diesels as I am about the Atomic Four. There was a fair bit of cheap diesel crap on the market that, while eliminating the gasoline hazard, didn't present any advantage in performance, efficiency, NVH, or maintenance.

[rslifkin]

10 percent ethanol isn't the end of the world. Start with a clean fuel tank, modern-ish fuel lines (rubber lines made since the 90s are alcohol resistant) and possibly a carb rebuild depending on what the seals are. After that, use fuel stabilizer in anything you won't burn in a month.

My boat ran on E10 for 15 years (nothing else available) and once the engine carbs and fuel lines were taken care of, no issues. Fuel sitting all winter has never been an issue either. And the generator carb was never bothered by ethanol and is going on 35 years, never rebuilt.

[hamburking]

I owned a C&C27mk2 with an atomic 4 and later a C&C27mk4 with a yanmar 2GMF. So essentially same boat, different engine....exactly the comparison you are asking about.

Both engines were well maintained and reliable.

The A4 consumed about 1 gallon per hour, the yanmar 1 litre per hour. So the yanmar had MUCH greater range. Travelling around Lake Ontario with the A4 had me filling the gas tank at every marina. With the yanmar, I topped up the tank once per year, before haulout. Massively greater range is a huge deal on a sailboat.

Both are noisy and smelly.

Outboards are great in smooth water. Useless when the waves get big.

So, in conclusion, go electric.

As for boats to buy in your price range....Pearson 30 (mid 70's) would be ideal for you. C&C29mk1 (better than the C&C30mk1), or a Cape Dory 30. Enjoy.

[Time2Go]

Spend some time at
“Moyers Marine” website
for all things A4
My Ericsson 27 had one
No Problems, Great On-Line support groups
Just be mindful that you have gasoline on board
Cheers
Neil

[GusC]

Thanks!!! I am considering this C&C and wanted to get your opinion, since you have had 2 of these https://milwaukee.craigslist.org/boa...221784864.html

Thanks a lot for your opinion!

[Jim Cate]

Opinion noted. Supporting facts would be nice, but understood its a popular opinion.

I thought I'd covered some facts in my earlier post. PErhaps if you read that you would see the basis for my opinion.

Jim

[mvweebles]

Originally Posted by Jim Cate

I thought I'd covered some facts in my earlier post. PErhaps if you read that you would see the basis for my opinion.

Jim

Yes, weaving back through the 40+ posts I suppose you did offer your anecdotal experience. I would note the article I linked addresses these concerns, including lack of main bearings. Seems like a knowledgeable source, but I don't know for sure. All I can tell you (anecdotally) is the diesel alternative - the Universal 5411 - is no great shakes. As others have said, there's more to the story than the oft-parroted "diesel good; gas bad."

Makes me understand why the Pardeys opted for rowing stakes instead of an engine.

Peter