55hp evinrude fuel pump bad?

I've got this 1969 55hp evinrude that I had running a couple weeks ago. I've posted a few threads about it but no luck. I've tore down the carb's and cleaned them out,replaced fuel lines, new fuel and all and it still won't fire up. IT will start up but only stay running as long as the key is in the start position and the starter is turning. As soon as I let go the engine stops.<br />One guy suggested iginition switch but it's brand new. Could it be the fuel pump maybe? IT's getting pleanty of spark and fuel to the spark plugs, but still nothing. Could it be a bad ground, I did lose power to my purple wire running to the switch box. I added power to the green wire and it switchs into neutral fine. Any thoughts?

Re: 55hp evinrude fuel pump bad?

From your description, the problem sounds as if it is an electrical problem. I suspect that you may have a bad amplifier or a problem on the purple wire leading to it. To check the amplifier connect a jumper lead between the black and white lead terminal from the breaker points and the black and white terminal on the amplifier. Connect a low reading amp meter between the purple lead connectors. With the ignition switch on, engine not running,ammeter should read .2 amps. Check to find out why you lost voltage on the purple wire to the amplifier and correct it; without it the amplifier will not work.The amplifier may be receiving a secondary battery voltage through a defective blocking diode while the engine is cranking. Hope this helps.

Re: 55hp evinrude fuel pump bad?

Thank you so much o/b tech!! I will get right on that. I had voltage to the purple wire whe it was first running a couple weeks ago but it suddenly just lost it, so I'll put my money on you. thanks alot again I'll let you know how it goes.