Starter fuse blows when key pushed on start

I recently bought a boat with a 1983 90hp Mercury 6 cylinder outboard. I noticed today, whenever I push in on the key and then turn to start the engine the fuse in the engine (starter circuit) blows. If I simply turn the key without pushing the engine turns over fine and with enough time I can get it to start. As I understand it from my reading here and other sites, pushing on the key activate the enrichener on the engine.

I am wondering if anyone has suggestions on how to diagnose the problem. I am assuming either the enrichener is shorted or there is a short in the circuit for the enrichener. Is there a test I can do on the enrichener to determine if it is bad?

I appreciate any suggestions anyone has on tracking this down.

Re: Starter fuse blows when key pushed on start

I am wondering if anyone has suggestions on how to diagnose the problem. I am assuming either the enrichener is shorted or there is a short in the circuit for the enrichener. Is there a test I can do on the enrichener to determine if it is bad?

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Ayuh,... Sounds like ya found Where to look,...

Now ya just gotta Look....

Either you'll find a bare wire short, or the unit has an internal short...

Re: Starter fuse blows when key pushed on start

Possibly just a bad key switch.It's time to get the O'll ohm meter out.

Re: Starter fuse blows when key pushed on start

Bond-o said:

Ayuh,... Sounds like ya found Where to look,...

Now ya just gotta Look....

Either you'll find a bare wire short, or the unit has an internal short...

Click to expand...

Thanks for the confirmation on the likely place to look. I came to this conclusion mostly by a bunch of reading on the web and was not entirely confident this was the right place to start. I will probably sacrifice a few fuses and start with some testing.

1) Disconnect the wires from the enrichener and push in the key and see if it blows a fuse. If not then the problem is likely the enrichener...
2) If it still blows a fuse, then I guess I dig in further in the wiring between key and junction block on the engine to find a short.

Re: Starter fuse blows when key pushed on start

ENSIGN said:

Possibly just a bad key switch.It's time to get the O'll ohm meter out.

Click to expand...

Any advice on how to test the switch. I am not real sure how to approach this. I guess maybe I should test for an open circuit to ground on the wire going to the enrichener. Otherwise I am not sure how to test this.