evinrude keeps running

sorry hit wrong key, iwould turn off key and engine would idle after 30 to 90 seconds would stall out. when key was turned off all guages shut down. also sometimes it would shut corectly other times no. i had omc tuner and tried it in case of carbon build up, got minimal heavy exhaust. after twelve proper shut offs started again. i then replaced with omc original switch which is set up for safety lanyard which i don't have started engine and it continued to run, i tried several more times and it shut off properly. engine is 96 evinrude 150 carb.with vro, engine appeared to have low hours. also changed plugs after tuner. thanks

Re: evinrude keeps running

Welcome!!<br /><br />Welcome!!<br /><br />Welcome!!<br /><br />Sorry, couldnt resist. OK, without looking at a wiring diagram this may not make much sense. The kill circuit (black wire with yellow tracer) at some point goes thru the shift interrupter (mounted on the starboard side on the shift rod). I'd almost bet there's a break or bad connection in that wire somewhere. If that wire is open (broken or not connecting) when you shut the key off only the port side will ground out. The motor will continue to run on the starboard side.<br /><br />Make any sense?

Re: evinrude keeps running

Dhadley thanks for the welcome. thats something else i can try. if i understand it right wouldn't the engine run rough mine seems to run at normal idle till it cuts out. i can also turn the keyback on feel slight reconnect bump and she ready to go. thanks for the comeback

Re: evinrude keeps running

When you shut the key off on a magneto system, which is basically what you have, the key actually grounds out the ignition. That circuit goes from ground to the key switch and then back to the pack. Its basically one wire to the pack except for the interruptor switch. I suspect we will find a bad spot in that circuit (from the pack to the interruptor switch and back to the pack).<br /><br />The bad place in the wire will allow the connection to be made sometimes and not at other times.<br /><br />Idealy youd like to check the spark when this happens. Youd most likely have no spark on the port side and good spark on the startboard side with the key in the "Off" position. Obviously if the key shuts the motor off it will test good.

Re: evinrude keeps running

302, <br /><br />Did you find the problem...I am having a similar intermittent problem

Re: evinrude keeps running

mark sorry I haven't totally corrected it yet. I'm a weekender at my marina taking 2nd and 3rd week july for vacation will track it down then. I did try decarbing engine had minanal smoke don't think that was the problem also using fuel treatment now for carbon. Replaced original omc ignition identical part still continued to happen. So now I will try for bad ground and also check shift interupter. Also check this site for "kill switch" some more information there. Once i correct problem i get back on and will be checking periodically. I dont have a computer at home. Good luck this is a great forum.

Re: evinrude keeps running

Mark took the boat out friday problem was worse continued to run for about 3 minutes couldn't take it anymore parked the boat and begged the mechanic to check it out. Came over saturday long story short removed cover plate top of engine exposing harness connection he noticed wires really tight, cut back the tape wrapping wires pressing them back in the harness started and stopped it ten times no problem went back on sunday tried ten more times no problem. Got lucky hope yours is an easy fix to. good luck. Thanks everybody for your help.