Breakerless ignition conversions

[jdemaris]

I asked this as an aside in another post but figured I’d be more specific here. I’ve got many old outboards from the mid 30s up to the early 70s. Mostly in the 1.5 to 5 HP ranges. 2 stroke-cycle and 4 stroke-cycle, single cylinder and twin cylinder. One thing in common. I get them running – use a little for one season, put them away for a few years – and then no spark. I only use them for kickers in case my main engine dies out in Lake Huron. So when I DO have one mounted – it only gets run in a test or an emergency. I’ve grown a little tired of pulling off flywheels and filing points, just to have them oxidize again when in storage. I’d like to convert a few to breakerless.

ATOM of Australia used to sell little conversion modules and had many different types. For outboards – they sold one for fixed breaker-plates that did not advance timing with throttle, and another for units that did. Now – ATOM is gone, but I see other brands and from what I can tell – only one version to almost "fit all." I understand how breaker-ignition works. What I do NOT understand is how these modules get the timing correct when there is no longer any adjustment. No gap to set or breaker-plate to rotate. Any successful users of these newer modules like from Omega or Stens?

I converted my 55 horse four-stroke-cycle Fisher-Pierce to Petronix breakerless years ago and that has been great. But that Crosley engine has a real distributor I can rotate an still adjust timing. Not the case on these little outboards if I stick a module in them.

[chris-p]

A few members have tried the Novas, only to have them fail.

The ATOMs work great, if you can still find them. Used to be able to get them online, but try checking ebay from time to time.

I bought a few Novas to use one day, but I think it was Wedgie or Mumbles stated that they ended up failing, so I haven’t tried them.

You can also make your own. there are a couple members that have posted instructions on the forum here. A bit beyond the understanding of my little brain, but if you have electronics experience, something you may be able to do.

[jdemaris]

I still have a box full of new ATOMs from when I worked at a small-engine repair place. All I have are the brown ones. At the time, not the ones ATOM recommended for outboards. Two-stroke-cycle trimmers and chainsaws – yes. How that differs from an outboard is beyond me.

[Mumbles]

What you want are the RED Atom Modules for your outboard.

Here’s a link to a really long thread about the Atoms!

viewtopic.php?f=2&t=1050&hilit=atom+module

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[amuller]

The Atomic thread is extremely learned and interesting. It’s got me motivated to try making these–probably a winter project. Not sure there is a single post with a bill of materials and sources, which would be helpful.

[rudderless]

The items are listed on the schematics, with detailed explanation in the text. I bought 2 atoms for my ’76 omc15 and am anxious to install them. It is impossible with the clearance needed for the top needle bearing to hold proper point clearance. I’ve used a timing light on mine with new upper bearing and tight stator plate and the timing bounces around quite a bit depending on rpm.

[jdemaris]

Anybody have any idea what the difference is between those red ATOMs and the brown ones like I have? I’ve seen the ATOM literature and that company sure seemed to think there was a difference. The new ones I see from other companies are advertised as "one product fits all."

[rudderless]

Read the atom thread..it explains it all about the various types of atoms and why…

[Mumbles]

quote jdemaris:

The new ones I see from other companies are advertised as “one product fits all.”

If you mean the Nova II’s, do yourself a favor and save your money for the real things. I have a dozen or so junk ones sitting here as they would not hold up in the OMC magnetos. They lasted anywhere from thirty seconds to thirty minutes before failing. 🙁

[jdemaris]

I read all the pages linked to about the Atom. Nothing there (unless I missed it) that explains the difference between a red module and a purple module and it seems the ones being copied are based on the red.

I have a bunch of new-old-stock Atom brown modules and am wondering how they differ from the purple. # 209 brown is listed for two-stroke chainsaws and trimmers, whereas #7 purple is listed for outboard motors with fixed timing. Seems going by the description – they both do the same thing.

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