Emergency Start/Charging issues

[HardHead]

I am having an issue with my 1996 370 Sea Ray Sundancer with 7.4 Mercruisers. The other day I started my port engine, no problem. I went to start my starboard engine and it would not start, but the alarms did sound, but no noises from the solenoid or the starter. I pushed my emergency start button and it started right up, but unfortunately both battery gauges showed that they were discharging at less than 12 volts. I took the boat out and ran it around for about an hour and got back and shut down the engines. After about 30 minutes, I started the Port engine again, no problem. I attempted to start the starboard and it would not start again. I again used the emergency start button, but all I heard was a click. It would not start the engine this time. I jumped the solenoid on the starter and it started right up with both batteries still discharging. Here is where it gets weird, the next day I started both motors with no problem and now the batteries are charging on the port side just under 14 volts and the starboard is charging about 13.5. I am thinking that it is the slave solenoid for the emergency start button but does anybody have any other ideas. By the way, I did replace the starboard engine battery even though it tested fine. I appreciate any help anybody could give me!

 

[SCORPIO]

I'd be more inclined to think that the voltage regulator on you starboard engine is having an issue. Either that or you have a bad cell in one of your batteries causing a high charging load that you alternators can't match. I'd load test all your batteries and see if they all read good. You may need to check alternator output to see if they are both charging. I'm assuming here that you have dual alternators.

 

[HardHead]

Batteries checked out ok...I even replaced one on the starboard side. I'd agree with you but the batteries went to discharge only when I used the emergency start and the next day it was charging on both sides 13.8 to 14.

 

[Mike Blake]

CHARGE, then draw test the batteries. I have seen NEW BAD ones. Check all grounds and make sure the shifter is in neutral Then go ahead and check the charging system.

 

[JVM225]

Swap the ignition switches from one side to the other and see if the problem switches motors.

 

[HardHead]

After further investigation, I swapped out the slave solenoids....still would not start. I bypassed the neutral safety switch...it started and charged every time. So you would think it was the witch right? Wrong, replaced the switch...it would not start. I messed with the linkage a the transmission...it started and charged. It looks like the lock nut had come loose on the attachment to the shifter at the transmission, so I adjusted the cable at the transmission and tightened the lock nut. It stats an charges each time. I'm not sure why it wasn't charging, but it's working now. Wow,did I learn a lot about my engine's starting system!!