Alternator Chronicles – A Happy Ending

So you recall a few weeks ago we “blew up our alternator” while trying to do diagnostics on a suspected charging problem.  That was a big bummer, requiring ordering a new alternator and regulator, shipping from the West Coast of the United States, and import duties into Spain.  Ouch, ouch, and ouch again.

Well, this story has a happy ending, but bear with me, while I get us from point A to point B.

We drove over to Porto this past weekend with goal of the getting the engine operational so we can go sailing in September.  Saturday morning I tackled some easy tasks around the boat.  Basically, I wanted to have some accomplishments to get me in a “can do it mood” before I started on the challenging, potentially unsuccessful task of replacing the alternator and regulator.  When I settled into the task I started by checking every connection between the alternator, starter, and the batteries looking for loose connections, corroded connections, or otherwise inconsistent ohm readings.  Everything looked good.  Then the regulator swap out was just a few painless minutes.  Feeling good about this so far.

Afterwards, I took photos of the old alternator wiring in case I had doubts when hooking up the new alternator.  Swapped out the alternator and ran into a snag when the positive terminal bolt on the back of the alternator was about 1mm too long and would hit the engine block when the belt was tensioned properly.  No bueno.  Indeed the dead alternator had received a bolt haircut for the same reason.  So it is unbolt and unwire the alternator and cut a little off the bolt, then put everything back into place.  The “pre-flight” checks all looked good and at this point we can see no reason why all systems aren’t ready to go.

Fire up the engine and after a short delay the amps are positive and the alternator is working!  Success?  A few seconds later the amps nose-dive into the negative territory.  Smokes starts coming out from behind the NEW alternator and the 250 amp slow blow fuse on the house batteries blows again.  Total f’ing disaster.  I was dumbstruck and distraught at the same time.  Did I really just smoke ANOTHER $$$ alternator?  As I’m pondering that depressing thought I peer around behind the alternator and lo, the smoke is not coming from the alternator but the starter solenoid just behind the alternator.  From the front of the engine that is basically the same space, but from the side I see a completely different situation.  A Eureka of sorts.  Maybe I didn’t smoke the alternator, but did I blow the diodes when the fuse to the house battery blew?  Well, diodes are much easier and cheaper to fix than a new alternator.  But, what the hell is going wrong?

Already at this point, I’m thinking, hmm… if the smoke is coming from the starter, maybe I didn’t blow up the first alternator either…  But I still don’t have a working solution.

So, now I’m ready to place the blame squarely on the starter or starter solenoid.  It just happens I have a spare one of those.  I grab the box, yank out the replacement starter and my hopes are dashed.  It looks nothing like the original starter.  I can’t see how the new one can bolt up.  That might explain the $75 I paid for what is normally a $500 part.  Maybe this starter is for a Yanmar powered tractor, or something.

All I could think of at this point was to remove the old starter and see if we can get it repaired, so I proceed to remove the old starter.  That requires a trip to the store because a socket won’t fit on one of the bolts and I don’t have a box wrench big enough (17mm) for the job.  Once the starter is removed, I place it next to the spare.  Wait a minute!  Despite being totally different in size and shape, the bolt holes do actually match.  Maybe, just maybe this will work?  5 minutes later the spare starter is bolted on and wired up.  Okay, once again things are looking up and I’m feeling good that we’ve solved the problem.  Let’s kick the engine over and see what we’ve got.

Nope.  No dice.  We are back to square one.  The engine runs, but we are getting negative current  and NOW we are back to an earlier problem.  The engine won’t shut off.  We spend several minutes trying to come up with a way to stop the engine.  Nothing works.  Finally, we cross our fingers and just turn off the key.  At this point I can’t think of how that would create more damage, everything involved is already broken…  The engine shuts down immediately.  What the hell though?  New regulator, new alternator, new starter, and same old problem.  Time for a walk with the dogs to ponder the situation.

Okay, you may have already figured it out, and if not the suspense is probably killing you, so I’ll cut to the chase.  After the returning from the walk, I grabbed a can of WD-40, sprayed the ignition key, turned it on and off a few times with the battery switch off (so the engine wouldn’t start), turned the batteries back on, started the engine and did the happy dance for the rest of the day.  Starter works, alternator works, regulator works, engine shuts down!!!!  After upteen hours and upteen dollars, replacing the regulator, alternator, and starter, it turned out that 10-seconds with a can of WD-40 solved the problem.  The REAL problem, it turns out, was a corroded ignition key/ignition that was preventing the key from returning to ON from START after starting the engine and releasing the key.  So, the starter would just keep running and running and running until smoke started coming out of it.

Ouch.  That was a hard, hard lesson for such a simple, simple problem.  I feel like I just earned a PhD in mathematics in order to answer the question what is 1+1.  On the bright side I now know how to replace the alternator and starter, I’m familiar with all of the associated wiring, and I replaced the alternator belt which made the engine immensely quieter and might have been the cause of the original problem with low alternator output (belt slippage).

In the end we celebrated a hard fought battle.  I’m hoping this was our baptism by fire in our return to boat ownership.

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