Due to Covid-19, I have sailed zero days (minutes) this year. The boat is in the water (necessary for anti-fouling) but it hasn't moved out of the slip.
Today I wanted to start the Atomic 4 to move the prop a little, and perhaps even the boat and go swimming or something. To my surprise, for the first time since I have the boat (19 years), it did not start! Starter fluid did not help, I have no reason to assume anything is wrong with compression, so I suspected ignition. Indeed, no spark at the plugs and, as I then found, at the coil when I turn over the motor.
To check the coil, I shorted the negative side of the coil to ground with the ignition on and got a beautiful spark at the HV cable. So, coil is fine, looks like either condenser or points. I suspected the condenser but it measured at 220nF, same as the brand new one in my spares collection.
So it must be the points. Hard to see how they can go wrong but there must be a reason. So I measured resistance between the cable and ground and get infinity when they are open, as expected. So far so expected.
Now it gets weird. I had by now taken the plate with the points out (to check on the flyweights since I hadn't done that in years; they are fine) so it was easy to open and close the points. To my surprise, I am getting infinity also when they are closed!
Hmm. Maybe some corrosion? I wiped some fine sandpaper between them. No change. Hmmmm. Something fundamentally wrong with the old points that I somehow cannot see?
So I break out the brand new spare points, still sealed in their packaging. Just to make sure, I measure resistance when open (infinite, good) and when closed (infinite!!! WTH???).
What is going on? It is not my VOM; when I measure from the cable to the 'near' part of the points (the one connected to it) I get 0 Ohm, of course. But on the other side it is infinite.
Is there some insulator between the two contacts? But how can the whole thing then work? It needs to establish a low-resistance connection when closed to generated the magnetic field in the coil.
Again, what is going on??? Utterly confused
Today I wanted to start the Atomic 4 to move the prop a little, and perhaps even the boat and go swimming or something. To my surprise, for the first time since I have the boat (19 years), it did not start! Starter fluid did not help, I have no reason to assume anything is wrong with compression, so I suspected ignition. Indeed, no spark at the plugs and, as I then found, at the coil when I turn over the motor.
To check the coil, I shorted the negative side of the coil to ground with the ignition on and got a beautiful spark at the HV cable. So, coil is fine, looks like either condenser or points. I suspected the condenser but it measured at 220nF, same as the brand new one in my spares collection.
So it must be the points. Hard to see how they can go wrong but there must be a reason. So I measured resistance between the cable and ground and get infinity when they are open, as expected. So far so expected.
Now it gets weird. I had by now taken the plate with the points out (to check on the flyweights since I hadn't done that in years; they are fine) so it was easy to open and close the points. To my surprise, I am getting infinity also when they are closed!
Hmm. Maybe some corrosion? I wiped some fine sandpaper between them. No change. Hmmmm. Something fundamentally wrong with the old points that I somehow cannot see?
So I break out the brand new spare points, still sealed in their packaging. Just to make sure, I measure resistance when open (infinite, good) and when closed (infinite!!! WTH???).
What is going on? It is not my VOM; when I measure from the cable to the 'near' part of the points (the one connected to it) I get 0 Ohm, of course. But on the other side it is infinite.
Is there some insulator between the two contacts? But how can the whole thing then work? It needs to establish a low-resistance connection when closed to generated the magnetic field in the coil.
Again, what is going on??? Utterly confused
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