motor continues too run with key off

[nektwister]

Hi guys just recently started the rig up for a spring running and everything went great ran the boat up and down the river for at least an hour no troubles but when I shut her down the motor continued to spit and sputter I eventually had to choke it to get it off I then tried too restart it and had a heck of a time and there again when i shut it off it continued too spit and sputter I'm thinkin carb problems the motor is a 1979 V4 115 and thanks for the help any and everytime. GIT R DUN

 

[v12mac]

Re: motor continues too run with key off

I stand corrected <br /><br />Mac

 

[Joe Reeves]

Re: motor continues too run with key off

That engine has dual powerpacks. By "spit and sputter", I assume that you're saying that when you turn the key to the off position, the engine does not stay running at the same rpm but rather drops off to a rough running rpm mode.<br /><br />If this is the case, the key switch is working okay but only one of the powerpacks is grounding out. This results in having the engine continuing to run on two cylinders. It should be a simple matter to find out which two cylinders are still firing.<br /><br />The black/yellow wire leading to the powerpack is the kill circuit. Check it with a ohm meter. With the key in the off position, it should register as being grounded (full reading of the meter scale).<br /><br />If it does not, find out why. if it does, check the black wire leading from the powerpack to ground to make sure that it is clean and tight.<br /><br />If the wiring is correct (all grounds clean and tight) and the black/yellow wire registers a ground with the key off, the only resulting cause would be a failed kill circuit within the powerpack.

 

[rodbolt]

Re: motor continues too run with key off

what joe says.<br /> most likly the isolation diode in one of the packs faled. someplace in the service manual there is a test for them. be aware that the side that is still sparking with the key off may or may not be the bad side.

 

[Joe Reeves]

Re: motor continues too run with key off

That diode test is to have a ohm meter and connect the meter leads between the white wire and the black/yellow wire, then reverse the leads.<br /><br />A good diode will show a reading in one direction but not the other. However, a bad diode results in having two cylinders fire at the same time, not the problem you have.

 

[nektwister]

Re: motor continues too run with key off

Thanks joe and everyone else kinda new the key switch wasnt it just replaced it with a new one and also new kill switch one of the power packs has been replaced cheked the older one with the meter and sure enough the culprit has been found. Thanks to everyone and Happy Easter...... was that politically correct nope just american GIT R DUN

 

[v12mac]

Re: motor continues too run with key off

I stand corrected.<br />Mac

 

[rodbolt]

Re: motor continues too run with key off

joe<br /> I have had to many that the diode failed and when the engine was shut off with the key it will drop 400 rpm and continue to run. but sometimes the side that was stillsparking(verified with a KV tester) was not always the side that failed. I have seen way to many v4-v6 pack failures that the complaint was it wont turn off just drops RPM. I am not the ang a neer but nor am I a maytag men I just fix em.