“The boat is the infection!!!”

[ndutton]

Typically those Merc 94A alternators are Delco 10Si models. Make sure it's ignition proof as evidenced by the screen shield on the side opposite the pulley stamped with "SAE J1171" on the center hub.

[joe_db]

When I used a 10si I had to use a slightly longer belt and the Moyer long version alternator bracket. The bracket can be used for the original Motorola alternators as well.
I think I had a 100 or 110 amp 10si and I never got more than maybe 50 amps out of it.

[ndutton]

Yes Joe, we are limited in alternator output by our low RPM. If you remember Hanley's alternator drive system off the flywheel with a larger pulley ratio and dual belts, he could get closer to rated output with it that we can with our stock accessory drive. However, looking at the same 35A load on our original Motorola 35A alternator compared to a 100A Delco, the Motorola will be running at max while the Delco will cruise along at 35% of its rating.

I had to slightly modify my alternator bracket for the 10Si to fit. A few minutes with a grinder did the trick.

[joe_db]

I did not have that issue with mine, maybe I would have with the standard belt.
I am still puzzled by the original issue, there are plenty of ways to make the engine battery just go dead with a bad system design or component failure, but random intermittent shutdowns would be a trick. I am not sure if I could design something to do that on purpose.

[ndutton]

Joe, whatever went on Bryan was able to isolate it. Remember this passage from the first post of this thread:

I traced back the electrical and then disconnected the house battery and all chargers. No issues. Connected to just the house battery, no issues. Reconnect the charger between banks and again failure after failure. I removed the charger that managed the charge between the two battery banks and voila..... no more issues.

I asked about it but did not get a response that I remember, exactly what is this charger he determined to be the problem? From the narrative I think it's an automated charge combiner but whatever it is, it apparently was intermittently dropping the ignition voltage low enough to stop the engine. As I recall the alternator guy recommended a charge management system (battery switch) that did away with the automation and the poltergeist was exorcised.

[joe_db]

Joe, whatever went on Bryan was able to isolate it. Remember this passage from the first post of this thread:
I asked about it but did not get a response that I remember, exactly what is this charger he determined to be the problem? From the narrative I think it's an automated charge combiner but whatever it is, it apparently was intermittently dropping the ignition voltage low enough to stop the engine. As I recall the alternator guy recommended a charge management system (battery switch) that did away with the automation and the poltergeist was exorcised.

That still doesn't make much sense. I can see it running the battery down, but then the battery would be down a few minutes later too.

"The few shutdowns that happened in 2017 seemed to happen after approximately 2 hours of motoring. The engine could be restarted and the trips could be completed without further issue. "

There are a few different technologies around. I have an automated combiner relay that replicated a person combing the batteries and then un-combining them. The worst thing it could do would be not work, in which case the battery would eventually go dead or a human would notice and turn the manual switch.
There are DC-DC chargers with various brand names like Echo Charger. They are essentially DC powered battery chargers that aim to supply a start battery with a voltage tailored to it from a big house bank that might have much higher voltages. They are not combiners and do not pass current directly. They have a limited current output like any battery charger. They have a variety of possible failure modes including just flat out not being able to keep up with what the engine systems use. If one became randomly intermittent I suppose it could run the engine battery down, cause the engine to quit, and them spontaneously start working again a little while later. This would be very very obvious if one had a voltmeter.
I never really trusted those things and never installed one without a manual bypass.

[ndutton]

I don't see how any analysis can be done when we don't even know for certain what sort of device was found to be the problem. Without additional information it's pretty clear that Bryan - - with the help of others - - found the problem, confirmed by successful resolution when that one component was removed. We also don't know the ignition path on Bryan's particular boat when the apparently faulty device was installed.

[Bryan Janeway]

Hello all and thank you for your continued interest.

Dutton that is the exact model I have installed and yes it is ignition protected.

I did have to modify the metal bracket with a grinder. Doing that I was able to use the standard arm and belt along with the tensioner I purchased last year.

I have been reading the replies in response to what was the actual problem. I posted that I would not name the brand of charger other than it is a “duo” charger. Google it and you will see what I am talking about. Once this charger was removed from the system my problems went away.

Now I don’t disagree with the poltergeist philosophy nor with the idea that something else may be wrong. I have spoken with a bunch of electrically inclined people and they believe my problem lies within the grounding system. The charger may have helped exacerbate the problem but was not likely the root cause. One question that I do have is what is the lowest voltage that will power the coil and provide spark or allow the faucet fuel pump to click away. I’m thinking that is just shy of 8 volts. Please correct me if I am wrong. A momentary voltage drop to whatever voltage that may be is most certainly the issue based on my initial analysis. That moment is about 5 seconds or so. I don’t know if the charger cycling through a float or a bulk charge is doing it, but it is happening with that charger installed.

Now I have been advised to not only inspect my grounds I have also been able asked to do load checks on the battery system. That includes not just the battery alone but individual leads both positive and negative. Being very aware of the fuse holder connections. The point being is a multimeter may show a near zero resistance indicating an intact power lead but a multimeter is a poor indicator of a quality connection. This is because once a power lead is loaded with start or charge amperage things change. I may yet have a faulty connection through a fuse holder or chaffing or who knows what.... I will be back on the boat in a few months to charge and inspect my gear and hopefully find a few more answers.

And yes I have purchased the xantrex echo charger to replace the original. I was told that the switching option initially suggested can become an issue and can fry your alternator even when being very careful.

Every day I learn something new. Hopefully your continued support will allow me to identify the root issue.

Please remember when I originally posted my point was not to toot my own horn it was merely to provide others in my situation additional ideas on how to refocus their energy and time. When I was dealing with my engine shut downs I focused 95% of my energy on the engine and it wasn’t until the end of the summer that I refocused on the electrical system. It was a frustrating season. I did learn a lot however a lot of sailing time was lost because my troubleshooting didn’t become effective until very late. I am still learning and accept that my troubleshooting may indeed not be over.

I thank all of you that continue to look through my posts and provide food for thought.

Have a great day

[Bryan Janeway]

Quick update...

Happy Sunday all and good afternoon.

I wanted to write a final chapter in the electrical saga of last year.

I would have to say that without a doubt I learned as much about sailing this year than I did about fixing the boat in 2018. Meaning only a few issues cropped up with ye old atomic.

1. Rough running engine early this spring, checked dwell, corrected gap, engine ran smooth. Made dwell check a regular thing, only needed to adjust it one other time.

2. Port tack while motor sailing in a stiff wind will get the intake up and out of the lake. Moyer marine emergency system picked up on that just about the same time I was wondering why the exhaust was so steamy. Sheet out more, reduce heel, problem not a problem.

3. Cold Lake Ontario causes fouled plugs and rough running engine. Needed to change a week ago and engine purrs through the snow showers wonderfully now. Keep looking at the cooling system upgrade..... but so far plugs are cheap and having an extra gapped set ready will do me just fine.

4. Last is cold stalling (I think).... I can sail to within a few hundred feet of my slip. I’d drop sail start engine, quick turn into finger, quick turn into slip, shift into reverse and blah.... one comment a mechanic made was “even you need a few minutes after a nap to get moving... give it half a chance!!”. So now I start engine at least a half mile out and that problem seems to have disappeared.

This season did not produce a single unexplained shut down only happy sailing and happy motoring. I was almost living on the boat and while work kept me closer than I wanted to be (on call). I was upwind and downwind and reaching and poled out and letting the spin fly. Lots of sunsets and sunrises a few dead calms and a pile of reefed and furled crazy sails going nowhere in particular as fast as my heavy boat could go and trying to figure out where the humming noises were coming from.. shrouds, hull, rudder???More than a few beers and good bbq too.

I still am asked, and think about the issues from 2018 and I am still told that a dc-dc duo charger shouldn’t do that and I do not disagree. But here I am November 10 about to go sailing in the rain and snow, very displeased with having my boat pulled this coming Friday. As much as I like skiing I will miss this summer and all the fun had, and the little engine that kept us moving when the wind was on our nose or not blowing at all.

I keep reading and loving this forum. I still learn lots and keep playing with everything and tear stuff apart and put them back together just to keep learning.

Thanks all. Now off to the boat..... maybe an extra jacket will come in handy tonight... 7cm of snow in the forecast

B

[ndutton]

Good post-season debriefing Bryan

2. Port tack while motor sailing in a stiff wind will get the intake up and out of the lake. Moyer marine emergency system picked up on that just about the same time I was wondering why the exhaust was so steamy. Sheet out more, reduce heel, problem not a problem.

That's why it's there. The issue was identified and remedied before it became a crisis (runaway temperature).

Excellent!

[chapster5]

“even you need a few minutes after a nap to get moving... give it half a chance!!”

Think we can all relate !!