Engine will not crank, even with ignition hand button.

[68PearsonRenegade]

Dropped in another A4 into my boat. 2 battery system, brand new batteries. Perko 1,2,both switch, link 10 monitor on a shunt, and a solid state isolator. It's a simple 2 battery system that I think I have my head wrapped around. Problem is the ignition switch does nothing. To troubleshoot this I got a push button ignition switch and attached it to the correct terminals. I heard a very faint clicking noise in the solenoid but it barely reacted to getting power. Seemed like it wasnt getting much power at all... scratching my head big time on this one. I'll draw up a schematic on the system and post it later.

[ndutton]

Troubleshooting 101, first step at the source.

What is the voltage at the battery posts at rest? Same test, same place when the starter button is pushed?

[68PearsonRenegade]

Thank you for that. I busted out my multimeter copy of this old boat and reread the electrical section. I'm sitting in front of the engine now and battery tested 12.6, starter terminal tested 12.6, push button ignition switch test under 1v when pushed.. so that's an issue. The solenoid is indeed getting basically no power when the circuit is completed. How should I go about troubleshooting this? From my understanding I have an open circuit/bad ground somewhere in the circuit correct?
Thanks again, as always.
I really really look forwards to posting a video of this engine running like a top in here.

[ndutton]

Did you take the voltage tests at the battery posts like I asked? There's a reason for it.

[Antibes]

Bad crimp or wire connections

[68PearsonRenegade]

Sure did. The posts read 12.67

[Dave Neptune]

Do you have a nice big fat ground strap on the motor to the batteries negative side?

Dave Neptune

[ndutton]

Sure did. The posts read 12.67

Excellent. As Antibes said, your problem is in the battery cables or their terminations/connections, either positive or negative or both. This includes the battery switch connections and possibly the shunt.

[68PearsonRenegade]

Do you have a nice big fat ground strap on the motor to the batteries negative side?

Dave Neptune

I have the negatives to both batteries connected to the monitor shunt and a main ground off of that.
You think I should have a ground on the starting battery negative to the block also?

[Dave Neptune]

With 2 lines you should be fine. Did you "unplug" the trailer type plug on the engine harness? They are notorious for lots of trouble. Could easily be a poor connection or switch too.

Dave Neptune

[68PearsonRenegade]

With 2 lines you should be fine. Did you "unplug" the trailer type plug on the engine harness? They are notorious for lots of trouble. Could easily be a poor connection or switch too.

Dave Neptune

was never one to unplug. The wiring is all redone so nothing is color coded or original. A lot of janky splices off of stuff. In the future I want to clean it up. Its been a real guessing game and wire tracing adventure.
I'm going to try adding another ground and also testing the areas posted above.

[68PearsonRenegade]

One other tidbit. The prop shaft is not connected to the engine... Does this effect its grounding? Its also on the hard so not in water. I'm no expert here but doesnt all of that essentially mean my engine block is not grounded at all?

[Surcouf]

prop shaft / being on the hard should not have any impact..;

just in case, a nice thread

https://www.moyermarineforum.com/forums/showthread.php?t=2685https://www.moyermarineforum.com/forums/showthread.php?t=2685

[68PearsonRenegade]

I left out my panel, fuel pump and solenoid. Heres a rough schematic of my system. I've been testing things this morning and once again noticed that the voltage drops to basically zero once I complete the "s" and hot wire circuit from the switch. The voltage is there... it's going somewhere.. just not into the solenoid.
One other thing to note, while testing my isolator(engine off) I notice around 8 volts at the input terminal coming from the ammeter/alternator... seems strange it would have any power when the alternators off..

[68PearsonRenegade]

Heres the schematic