Thursday, March 3, 2011

The Verdict is In...Atomic 4 Rebuild in Progress

I have decided, for many reasons, to go ahead and try to get a few more years out of the Atomic 4. Scott, yes, the same Scott that helped bring Skylark down to Jacksonville, will be pulling the engine and taking it back to his shop. Once there, we will decide if the decision is correct and the old A4 is worth saving.

To be honest, I would prefer to replace it with a diesel, but the cost of a complete replacement really adds up fast. Unless I luck out and find a used direct bolt up diesel, there would be a lot of fabrication work necessary to get another engine type to fit in it's place. A big part of it has to do with Skylark having a V-drive which limits my choices dramatically. So a new diesel replacement is now choice C. Choice B, which is still a possibility, would be to keep the A4 out all together, use all that wonderful space for storage and stick a 15hp long shaft outboard on the transom. Since I know I will be using the boat near shore, mostly on the river, ICW and Keys, this could be a possibility. But I am not a fan of outboards on a boat this size and will only go with this option if the A4 is DOA.

In general, the engine ran OK on the trip down. Now don't get me wrong, there were quite a few issues on the trip, but these issues came from areas not directly related to the core of the engine. That is what we are hoping for anyway as the problems we know about can probably (and hopefully) be fixed rather easily. The oil pan and carburetor being those main problems. Replacing both with new parts is quite affordable and if it fixes the main issues, I will be back in business. But until it's on Scott's workbench and he goes through it all, all I can do is guess. These engines are bullet proof, so I am hoping for a miracle.

Regardless of how I was going to proceed, the Atomic 4 had to come out. Obviously it needed to come out so we can see what we are working with, but in addition, it had to come out because the fuel tank needs to be replaced as well. The fuel tank, from what we can tell, is original to the boat and probably has 3 inches of sediment on the bottom. We learned that the hard way trying to keep the engine running in a rolly sea way. So to get the fuel tank out, the engine had to be removed.

If all goes according to plan, we will replace the oil pan, carburetor, change over to electronic ignition, replace the alternator and repaint the block to prevent corrosion. Of course the fuel tank will be replaced as well as the wiring from the engine to the house batteries. With that complete, the engine should last for a few more years giving me plenty of time to enjoy the sailing in Florida. The weather is really getting nice so I had to make the decision now. I will let you know what we find out.
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  1. I am sure you searched this and know, beta marine advertises their diesels with A4 mounts. Large chunk of money for sure. For my Pearson 424 they quoted 10.5k OUCH!
    I'm lucky my tank replacement will not require yanking the engine. Replacing with a split tank.
    Enjoy your blog, cheers.

  2. Herb n Laura, yes, I have looked at Beta marine a couple of times but as you mentioned, the cost is just too high to consider a new engine for a 42 year old boat. I will need to change the wording to say "Unless I luck out and find a USED direct bolt up diesel..."
    Love your blog by the way.
    Fair winds...

  3. Hi Jim,

    seems like a wise choice. It's tough to justify $10k plus on a repower, all things considered. And by the time a new prop/shaft/etc. etc. is factored in, plus probably re-worked engine beds.... Seems like folks that have rebuilt Atomic 4's are generally a happy bunch, from what I can tell.

    I have a VolvoPenta MD11c in mine, which I guess got put in in the mid 80's. It has raw water cooling, which isn't ideal, but my boat lives in fresh water, so maybe it's ok. I'd love to put in something new and modern....maybe some day. For the time being, it's been solid and reliable. I only mention it because from what I can tell, it seems a direct bolt-up to the Walter V-drive. It doesn't appear that the beds were changed for the install. I know there are lots of MD11c's out there, having been stock in Pearson 323's.....

    BTW, if you wouldn't mind sending me a note via email, I would love to ask you a few questions about instruments and such....I'm getting ready to install a bunch of stuff--wind, depth, knot-meter....not to mention auto-pilot, radar, gps. Oh yeah, and beef up the electrical.

    If you aren't too busy--
    pmsdemoman (at) gmail