Ignition breaker keeps popping
 

This just started on the last trip. The starboard ignition breaker pops when the key is turned to the "Run" position not "Start" within 1-3 seconds. The breaker will reset in a minute or two. If I pass straight thru the start up sequence it may or may not click the starter over. The Port side is working fine. I have since replaced both of the ignition switches with new ones and swapped the ignition breaker from port to starboard and starboard to port and the starboard still pops. It has become an issue slowly in the last few outings that the starboard side would not crank or rather engage the starter. At first I thought maybe it was the shifter lever neutral switch. But wiggling lever never really helped it just finally engage the starter when I kept trying to start it. I'm a little embarrassed by this part but I ran the starboard fuel tank empty on the last trip and after refueling it took 8 -10 cranking sequences to restart the engine. I waited between starts but could the starter have been the initial problem and repeated start attempts "cooked" it? The starter is only 1-1/2 years old. Or are there other things I should look at? Thanks in advance.

IF you are talking about the red 50 amp push button breaker.
Your alternator may be shorted out.
Remove the big red wire from the back of the alternator and see if the breaker stays in.

^^^^^^^^^^^ Check your engine grounds and open up the plugs in the mercruiser harness and inspect for corrosion. Starter solenoid may be shorting also.

The breaker in question is the black rubber one right next to the ignition key. But I may try the alternator wire thing. And its not the starter solenoid I swapped out the starters today. I guess all the little connectors are next. I hate chasing electrical gremlins.

That's the 20 amp ignition breaker, so this can be many things. Any of your gauges for that side and any or the engine powered items (fuel pump, coil, relays, alternator, etc). Don't know what motor, but if it has an electric fuel pump listen for it to power up, then if EFI pull the relays one at a time.

Its a 2000 Fountain w/500 EFIs. I have pulled the wires from the alternator and there is no change. I did notice that the "alarm" or "start signal" comes on the Port but not the Starboard side. Where are the relays that you are referring to?

With the alarm not coming on, pull the purple wire off, it should be behind the helm. If the alarm shorts out it will also pop the breaker. The relays are on top the motor, they look like small square cubs about 1.5 inch square

I have alot of purple wires. Do you mean the dark red with a white stripe? But now that you have mentioned it the fuel pump is not coming on. But before I start pulling pumps is there a breaker or fuse for the pump?

look for a connector with a grey/black cap on it back by the distributor, pull the cap and there should be three fuses , one is the fp fuse, pretty sure its the same one as the 502 mpi

Yes, the purple wire comes from the key switch to every, gauge, alarm, ECM, ALT everything that gets turned on. The alarm is small, about the size of a quarter (round) and about a 1/2 thick and is usually black. Alarm has one purple wire and the other side is a Tan/Blue wire. The Red/White is not what your looking for.