Tuesday, November 5, 2019

No bearing on the matter

We are under way southbound on the Tombigbee River, en route to Demopolis, Alabama. The river here in Demopolis pool is flooding, running nearly ten feet above normal pool. Since locking down at Howell Heflin lock, we've had two knots of current behind us.

We had a quiet and pleasant night Sunday; below decks in the stateroom you could hear the sound of the water rushing through the Bevill Dam gates. The water was glass calm, reflecting the sky. Other than one tow locking through in the evening, we had the whole place to ourselves.

Monday morning, fortified with my first cup of coffee, I called Juki, the sewing machine manufacturer, a little past 8am. Their US office is in Miami, an hour ahead of us. I was put right through to a support technician, Brian, in the home machine division (Juki actually makes and sells more commercial machines, but there is no overlap between lines).

After I spent perhaps a minute and a half describing the problem and all the diagnostic steps I had already taken, Brian knew immediately what the issue was. He first suggested bad brushes in the motor, but when I reported that I had checked them, that narrowed it down to a bad spot on the commutator on the motor armature.


Another view of the Snagboat Montgomery, from the visitor center.

The entire motor is considered what we used to call in the mainframe industry a "FRU" -- Field-Replaceable Unit. That means that when there's any kind of problem with it, you replace the whole thing; it's not meant to be taken apart and serviced. So, of course, I had not torn it down during my diagnostics, other than to check the brushes.

My ecstasy at learning that we only needed a $110 motor and not a whole sewing machine an order of magnitude more expensive was short-lived: replacement motors seemed to be on a two-week backorder from every distributor. I've already replaced this motor once, and it did not seem hard to find last time.

I had not really planned on spending the whole morning anchored at Bevill Lock, but we needed to figure out how to get either a new motor or a new machine before we missed the window to order things to Demopolis. So we hunkered down right there and I tore back into the machine.

The original motor died of bearing failure. Knowing it still had plenty of useful parts, including the armature, field windings, brushes, and the other bearing, I had squirreled it away as a hangar queen. I tore it open, looking to salvage the armature out of it. I also tore open the newer motor to discover that Brian was dead-on: there was a burnt spot on the commutator.


The seized bearing from the original motor, after I cut it off with a Dremel.

At the risk of oversharing the gory details, suffice it to say I ended up cutting the seized bearing off the old armature with my Dremel. The shaft was badly scored, but is at least functional installed in the newer motor. I put it all back together and the machine is again running like a champ. It's only a matter of time before the worn shaft wears out the newer bearing, so we still need a motor, but now I have time to wait for one a bit further along the route.

The repair took all morning, and we did not end up weighing anchor until 11:15. Two other pleasure boats were approaching the lock at that time, and so we scrambled to get the anchor up and lock through with them, rather than wait another full cycle or ask the lockmaster to do the extra work. We exited into the river by noon, and the other two loopers left us in the dust and were out of sight within an hour.

We had a very leisurely cruise, stopping right around the four-hour mark at a lovely oxbow of the old river at a place called Warsaw Bar. Both the river and the oxbow run to 40' deep in sections; we entered at the upriver end and dropped the hook in 22' along the north shore of the island (map). It was a quiet night with just a couple of tows passing out on the river. We had the whole oxbow to ourselves, whereas at least five loopers crammed into a much smaller anchorage downriver. Part of the canon, I suppose.

This morning we weighed anchor after a leisurely coffee, figuring to take two days to get to Demopolis. After an hour or so we arrived at the Howell Heflin Lock to find a tow locking up. We would have been in the lock in a jiffy had it not been for the fact that the tow did a crew change there, tying up the lock for an extra half hour. No matter, as we were in no rush.


Towboat Mr. David in the lock. If you look closely you will see he's sideways, pushed up against the lock wall for a crew change. He came through the lock hipped to the barges, and after the change he faced up to them and shoved out.

That having been said, even with the late start, we have so much following current that the plotter is telling me we will be in Demopolis before 5pm. Given that we have gorgeous weather this afternoon and again tomorrow, after which it will again become cold and miserable, we are considering pushing all the way to Demopolis today. Of course, a lot can happen between here and there, and this two-knot push can dwindle away to the point where we would arrive after dark. If that happens we will anchor upriver as planned.

Our last time through, off-season, we stayed at the marina there. It was nice enough, and that let us ride the scooters into town, but we have no need now of a return visit. We'll head to the anchorage instead, if there's room. As charted I would be concerned about depth at the entrance, except at nearly ten feet over pool we will have no trouble. Just as we did in Columbus, we'll lay down tracks for our exit in soundings good for the lower water level.

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