From: main@AmelYachtOwners.groups.io On Behalf Of Bill Kinney
Sent: Wednesday, July 14, 2021 10:23 AM
Subject: Re: [AmelYachtOwners] Intermittent starting issue
Intermittent failures can be such… fun.
If I understand correctly, when you have this issue with starting, the blowers do not run as well. That narrows down the likely causes quite a bit.
The key switch, or the wiring around it would be my prime suspect, although it could be other things too. 12V power comes from the engine, up to the key switch. When the switch is “ON” the power is sent back to the engine, and to the relays that turn on the blowers. If the blowers and the starter are showing common failure, then the fault must be before the wires divide on the positive side, or maybe after they come together on the negative side back to the battery.
Another place to look is the isolating relay in the ground wire. If that is intermittent in operation, or has bad contacts, to could interrupt the circuit on the return side. I think this is unlikely, because the blower negative return is connected on the battery side of this. Other than those two, its a matter of pulling and cleaning connections to be sure contact is good.
Key switches on both Volvo and Yanmar panels are not 100% waterproof, maybe a bit less so with the key left in. A drop or two of salt water inside, and things can get unreliable. I have never disassembled one to clean it, although I have replaced them.
Brunswick, GA, USA