I've gone the full round of sparring with Mr. Lehman, eventually got in two waza-ari, and came out victorious. And I have the cuts and bruises to prove it.
Earlier (Miami Connections) we rounded up the parts: Cole Hersee push-button starter switch and M202 solenoid.
The question is this: "Do you feel lucky, punk?"
We struggled with a replacement solenoid that was actually dysfunctional. The original solenoid tested okay on the work bench, but didn't fully work in the engine.
I'm not 100% sure, but I think I have a story.
It starts with rust. Lots of it. In two places: the starter button and the solenoid that kicks in the actual starter motor.
Mr. Lehman's starter motor is so huge that it would need bulky #8 wires up to the key switch and the starter button and back down to the engine. This is some heavy-duty (and expensive) wiring for an engine that otherwise can cope with #12 wire. There aren't many push-buttons that can handle the current flow, either.
The engineering solution to this problem is to use a solenoid on the engine. A small wire with very little current trips the solenoid. The solenoid uses two 6" lengths of bulky #10 wire to engage the starter motor. The starter uses #0 wire to the starter battery. It's ½" in diameter. Think wires almost as big as the copper pipe in your household plumbing.
Yesterday, I was pretty sure I saw only 10V going to the old solenoid. I just didn't get it at the time.
Based on today's results, I now theorize that If the solenoid is caked with rust, then some current is routed through the rust. Other current goes through the wires.
What made it more confusing yesterday was that the replacement solenoid — one that was was in the cache of spare parts when we bought the boat — was simply damaged internally. It clicked a little, but it never completed the primary circuit. It merely surrounded an already confusing problem with more smoke and noise.
I have now installed a new starter button to replace the old one which was flaky and which I destroyed unscrewing from the binnacle.
I have also installed the new M202 solenoid on the starter.
I turned on the engine alarm circuit. I hit the button.
Good crank. Immediate firing. Cooling water spraying out the exhaust. Oil pressure alarm silenced.
We have lift-off!
Here's the interesting bit. The voltage meter on the binnacle used to read about a volt less than the voltage shown on the main panel below. It always read a volt low. I assumed the gauge was crap.
Today, it read much closer to the system voltage as shown on the panel. The analog gauge looked like it was pointing at 14V which is almost the bulk charging voltage.
Now I'm convinced that it was corrosion in both the switch and the solenoid. The gauge was right all along; the engine wiring was crap. I'm wondering if this low voltage situation is the root cause for the hour meter on the tachometer not working.
Here's my theory: the wiring through starting circuit was somehow compromised, leading to two parallel circuits: one with relatively low resistance through the proper wires and one with relatively high resistance through rust and corrosion in the starter button and solenoid. Parallel resistors each take a share of the voltage. If the wire was 2Ω, and the rust was 10Ω then that might explain why 10V showed up at the solenoid. The other 2V were disappearing into a "short" circuit through the corrosion.
Having a theory to explain some of the anomalous readings on the multimeter makes me confident that I might actually understand what's going on.
Strange data means either measurement error or a wrong theory. A wrong theory of Mr. Lehman's wiring is a distressing thing. There aren't that many parts to the wiring in the first place: a failure to understand something so simple is a profound kick in the pants.
Now I'm happy and successful. And bruised. And I have muscle strains from many hours in awkward positions in the engine room.
I have fought with Mr. Lehman and yet again arrived at a completely victorious outcome. Mr. Lehman knows his role, and may be happier with proper wiring and voltage levels.
Moving to the Mooring
The net effect is that we've moved Red Ranger about ½ mile closer to shore. CA picked up the mooring ball on the first try — in 10-15 kts of wind. That kind of breeze creates an awkward situation that she handled nicely.
Picking up a mooring requires deft timing, a strong back, and staging the various lines in the right place to avoid fumbling around at the critical moments. She had all three elements.
Since the engine ran, I had hot water for a shower after my fight with Mr. Lehman.