Atomic 4 rebuild.

[Captain Crunch]

Hi All,

I'm faced with the ultimate decision: do I rebuild my A4 or replace with a diesel.

What's the general consensus on a rebuild? Do you think parts will be available for the next 10 years?

What's the approx. cost on a rebuild. I would be taking it on myself.

Any advice would be appreciated.

Thanks.

[ndutton]

Please describe your boat (make model, year, condition) and your interest in it both short and long term. All are important factors pertinent to the advice you seek.

[wristwister]

As Neil mentioned, the boat your dealing with and what your plans are for her plays into whether you do a $10K diesel swap or a $2K A4 rebuild. In most cases, a $10K diesel in a boat worth $5K doesn't make sense.

If you do decide to rebuild the A4, I can attest to how simple and gratifying that is. Here's my thread from the rebuild I did last year: http://www.moyermarineforum.com/foru...ad.php?t=10566

Total cost was around $1500, including Moyer parts and machine shop work. I'm a mediocre (at best) back yard mechanic with minimal tools, and with some guidance from Moyer and this forum I was able to pull it off.

[Al Schober]

Cost of an A4 overhaul - Wow! Tough question, but let me try..
Could be low cost - the first one I did was basically a gasket set, a set of rings, and a transmission oil seal. This engine was still running fine in the boat when I sold it 15 years later!
Beyond that, it's a question of what needs doing & what you decide to do. If the top of the block isn't flat, it's going to the shop for a skim cut. While it's there, they may as well do the valves and valve seats. Plus install the Kaminsky plug in the side of the transmission housing. How's your oil pressure? If not good, it might need bearings.
It depends on what you find as you get into it - but the nice thing is that these are in unit of $100. No $1000 surprises.
Another good thing about the rebuild is that everything fits. If you go diesel, you're starting from scratch. Do the engine mounts fit your bed? How about the engine cover - will it fit the diesel? Where's the exhaust? Does it fit your current run or will you have to reinvent an exhaust system.
Final question (I've got to ask) - what do you like best about a diesel? Is it the smell or the noise?

[Captain Crunch]

Thanks for the reply's!

Boat is a pretty good Newport 30 II. Someone definitely loved it before I acquired it 1 year ago. The family and I love it.

It was cheap, because of the A4. The A4 runs perfect, but seems a little tired. With a 5 and a 7 year old on board, I'm always thinking about it. It's hard to relax. I've had to push sailboats back to the marina a few times with the dingy.

I feel the boat is worth a motor upgrade but I would be willing to do the rebuild because I have the space to do it and I actually like the motor. Especially after doing the maintenance and all the research it seems like it would be worthy of a preventive maintenance rebuild.

My only concern is the availability of parts over the next 10 years. I'll probably own the boat for another 5 to 7 years.

Just looking for a few honest opinions of the availability of maintenance parts.

Thanks again for the reply's.

CC

[joe_db]

You may need neither a new engine nor a rebuilt one. Random stoppages frequently are caused by things like clogged fuel tanks or bad ignition coils. You might be $100 away from a reliable engine
Start with a block pressure test and compression test and we can go from there.

[ndutton]

Boat is a pretty good Newport 30 II. . . . . . The A4 runs perfect, but seems a little tired

Please elaborate. If it's running perfectly, what indications suggest it's tired?

I've had to push sailboats back to the marina a few times with the dingy

This boat or previous boats?

My only concern is the availability of parts over the next 10 years. I'll probably own the boat for another 5 to 7 years.

I think the parts availability for the Atomic 4 is vastly superior to any other small sailboat auxiliary engine. The Universal M25XP three cylinder diesel, the common successor to the Atomic 4 throughout the sailboat industry, is a horrific example. Volvo's might even be worse.

Then there's price and labor. The purchase price of a new diesel is only the beginning. You will also need to replace the shaft, prop, control cables, shift and throttle lever mechanism, some sort of exhaust modification, fuel tank, fuel fill deck plate, likely the raw water intake thru-hull (Capital Yachts used 1/2", you'll probably need at least a 3/4"), engine instrument panel, wiring harness, modify the engine stringers, engine mounts and those are what come immediately to mind. Check your available clearance above the existing A4 too. The N30II had very little clearance above the engine and because of the existing driveline angle you'll probably need at least another 5" in height for just about any diesel.

Since your engine runs perfectly, why not just take care of it and its ancillary systems as well as the previous owner did? If it hasn't been converted to FWC yet, do it. With that single upgrade you will arrest the internal cooling system rust instantly and prolong the engine's life indefinitely. Consider electronic ignition too, another significant upgrade if done properly.

[Captain Crunch]

The motor seems to lack power/torque, probably because its a 42 year old gasser. I sail in the Southern Gulf Islands, B.C. and have to deal with lots of current.

It has yet to let me down. I did overheat it for a while. 230*F Plugged raw water intake. It seems to not have affected it. It didn't even smell hot.

It definitely benefits from the MMO treatment. It's already FWC with electronic ignition. Runs great at 170*F full out. I usually back it off a bit and the boat cruses at 5 kn in flat water, but speed drops off quick with any chop or current.

We use the boat often and plan on a two to three month trip in a few years.

Seems like it may be worthy of a tear down.

Thanks all!

CC

[Peter]

Dear CC,

I wonder if some less drastic measures might be in order before you decide on the rebuild?

What is the compression like on the engine? If the compression is good I am not sure a complete rebuild would lead to increased power.

Have you set the timing recently?

Carburetor properly adjusted?

Choke fully opening?

Plugs properly gapped?

Is the exhaust back pressure ok? Your overheating incident may have lead to some internal degradation of the exhaust hoses which can reduce power.

And then the question of whether the prop is nice and clean and properly sized for your boat?

Appreciate your concern about safety with the little people on board.

Best,

Peter

[ndutton]

Before tearing down a good running engine I recommend a few tests/checks to be certain the perceived anemia is not because of a simple adjustment

• As Joe said earlier, compression test. It alone could indicate a tear down - - or not. Based on your description I'm betting not.
• Confirm the centrifugal advance moves freely and is lubricated.
• A PRECISE timing adjustment http://www.moyermarineforum.com/foru...ad.php?t=10351 please read the entire thread carefully.
• What are your prop dimensions? Direct drive A4's are often (regularly?) overpropped by the factory preventing the engine to really get up into the power curve RPM-wise.
• Exhaust system backpressure measurement. Moyer Marine has the necessary apparatus in their catalog. It's an involved test but way less effort and expense than engine removal and tear down. Does your boat have the factory original standpipe exhaust as opposed to a waterlift?

Peter types faster than me.

[Marty Levenson]

compression?

Hey CC,

Where are you in Gulf Islands? We used to keep our boat in Montague, May - September. Great cruising! Have you been to Wallace Island? We live on Bowen now, but I work in Vancouver a few days a week. I have a compression meter you are most welcome to borrow...? martylev (at) telus.net

+1 on the above advice. Even if you don't find a major problem to fix, methodically tweaking each factor might yield a noticeable improvement.

We also found that going to a three blade prop gave us more power. Locally, Campbell props are great. I imagine the Indigo is comparable.

Don't know your sailing experience, so forgive me if I'm telling you what you already know. You might get the government current atlas, as 5 knots might be good progress against a current you aren't aware of!

Finally, a good stash of spare parts does wonders for your confidence.

[wristwister]

CC, you're up here in the PNW? If so, I've got a shop full of A4 parts I've accumulated over the last couple years. In fact, I've probably got enough parts to build a whole 'nuther A4. I've considered doing this just for the heck of it, but it probably won't happen. If you do decide to take on a rebuild, keep me in mind if you need parts.

I sent you my rebuild journal. Hopefully you find some useful tidbits of info in there.

[Captain Crunch]

I sail out of Tsehum Harbour, Sidney, B.C.

Thanks for the advise on all the testing, tool offers and big thanks to Wrist for the journal!

I will start pulling the trigger on the testing. Glad to see that there is some confidence in part availability. I do like the A4 and would like to keep it.

Thanks for all the help.

CC

[jcwright]

Hello CC.

I see you’ve already received advice from others on rebuilding vs replacing your A4. To help you estimate costs, I will PM you my spreadsheet of all the parts (with MMI catalog numbers) I purchased during my rebuild. My bottom line was higher than Wristwister’s, and shows how my costs crept up as I replaced more than was truly needed. Let me know if you want my more detailed notes on the job and I’ll PM them as well.

Al, Neil and others note that much will depend on the condition of your A4 and how you intend to use it. Don Moyer gives guidance on this in the rebuild chapter of his A4 manual. Also to be factored in are the (possible) satisfaction of knowing your engine well and the self-reliance that comes with that.

If you do decide to go the rebuild route, I can assure you that this forum has the knowledge base needed for even a novice like myself to complete the job.

Best regards,

Jack

[nyvoyager]

I am in the same position but a bit more complicated and trying to decide what to do. Pearson 30 in decent shape - always needs some work
The other posts hit important points - money and time
Long story short - A4 block failed - bought a "rebuilt" A4 which wasn't. b It did however have a nice paint job...sigh

Yard moved my boat last week and damaged the mast so it just adds to the complexity.
I have talked to Ken at Moyer (Thanks Ken - you have been an enormous help)

Weighing my opinions:
Rebuilding is not an option for me (NY Condo)

A rebuilt Moyer A4
After two engines with block failures ( no reflection or offense to Moyer) I am simply gun shy about heading in this direction.

A new Moyer A4
This is a straight drop in and very likely the direction i will take

A Beta Marine
The Beta, while stated as a drop in for the A4, does require additional work and expense.
New shaft, prop, mod to fuel tank (not difficult) control panel and wiring harness. I am tempted
While it may not add to the resale value, it may help me sell the boat easier.

My rational is this:
I have owned this boat for plus 20 years and I like it. It owes me absolutely nothing.
I was planning on keeping the boat another 4 years, retire, upgrade and sail off
If my total investment is $8000 for 4 years, I can live with that.

On the other hand my daughter threw a wrench into my logic last night
She suggested i Leave the boat with the yard (they are willing), save all this money and buy the boat i want sooner. Smart kid.
I remain undecided as i am waiting to talk to the yard

Bottom line if at the end of the day I spent the money to repower and got the same $5k for th boat, I'd be fine.
The enjoyment factor has value
Best with your decision