Intermittent Starting Problem

[seasalt]

Sometimes my starboard Cummins 370 hp (mechanical) turns over and sometimes it does not. Just clicks and acts like a dead battery. Sometimes I move the shifter back and forth all the way to exercise the neutral safety switch and sometimes it rolls over and sometimes it does not. If not, I move all 4 battery (8D) switches to ALL and sometimes there is joy and sometimes not. If not, I press the parallel switch on the bridge and sometimes it rolls over and sometimes not. Today I did all the above and nothing worked. Then I tried it without any extra measures and it started. Go figure.

Until today one of the above procedures has always worked but I am stumped as to the cause. The 8D AGM battery is only 4 months old. It takes a charge well and unless the boat is not run for a day or two the starter engages as if nothing has ever been wrong.

This happened when I bought the boat in late July and all assumed it was the battery...so it was replaced.

Intermittent problems are hell. I wish things would just break and get it over with.

Any ideas?

[workingonadream]

well I guess it is now trial and error I love chasing the ghost. I would start by checking the voltage at the battery and then work your way inward toward the starter also check your start button I had a bad one in my engine room with similar symptoms sometimes it would work and sometimes it wouldn't. always works now that I changed it.

[SKYCHENEY]

Check all terminals for tightness and cleanliness. At that batteries, at the battery switches, and at the starter.

[rmatt]

Remove the fastener that attaches the ground cable to the engine block. Clean the cable and the area of the block where it attaches.

[Boatsb]

Remove the fastener that attaches the ground cable to the engine block. Clean the cable and the area of the block where it attaches.

X2. No ground means no juice.

[kelpy]

Replace and adjust the neutral safety switch.