Thanks to Steve Kaminsky for this wonderful tech tip:

If you subscribe to the Atomic 4 Engine Owners Discussion List sponsored by Sailnet.Net (https://www.sailnet.net), you may remember that a few months ago, Steve’s reversing gear failed to function in reverse. Inspection quickly revealed that the small roller broke free from the end of the brake band adjusting bolt. With this roller gone, the reversing bar moved freely (fore and aft) through the slot in the end of the adjusting bolt, with no ability to tighten the brake band around the gear cage assembly to engage reverse.

Upon hearing of Steve’s plight, we sent him a replacement adjusting bolt and the tools that we would use to replace the bolt if we had the engine in our shop. What makes this a particularly daunting repair is that there is insufficient clearance to slip the adjusting bolt out of the brake band without removing the entire aft housing. Poor access to the aft part of the engine in general, only added to Steve’s nightmare. We sat, holding our breath, waiting to hear back of his progress.

A few days later, I sat speechless in front of my computer screen as I read the account of how Steve (being unable to remove the aft housing due to even poorer access than originally anticipated) had drilled a hole in the side of the aft housing to remove the failed bolt and install the new one!

As an aside: As another subscriber to the list correctly pointed out, Steve’s wife was also a major hero in the saga, as she patiently and supportively stood by as Steve scratched his head, tooled up and finally performed the delicate surgery on their engine.

While we only hear of a roller failure every 5 or 6 years, it is one of those failures which can obviously be quite devastating when it does occur. For this reason, we have been looking for something that we could do at the time of an overhaul which would minimize the effects of a failure. Steve’s fix seems to us to meet the most important criteria when considering a change: It’s practically free, it’s simple, and it’s effective. We plan to capitalize on Steve’s experience by drilling and tapping a 3/4″ access hole in the side of the aft housings on all our exchange engines, and to offer the same option to our custom rebuild customers.

Here is a sequence of photos illustrating the modification, in case you decide to do it yourself while overhauling your own engine.

We still have frequent debate over the aesthetics of one plug type over another; but for now, we believe the basic 3/4″ pipe plug (such as you find under your carburetor in the upper part of the oil pan) looks as good as any. Brass hex-headed plugs seem to call undue attention to themselves, and allen-headed plugs require tools to remove that you may not have on board your boat.

In any case, thanks again, Steve, for a really innovative fix for a heretofore very perplexing issue.

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