170 merc electrical problem

[lewski]

hey guys,my 170 merc i/o has no voltage at the coil when the ignition switch is on.Could it be a faulty ignition switch or is it something else.It starts and runs fine with just a little backfiring if you put the thrott down to fast.Any thoughts would be a big help.

 

[stonyloam]

Re: 170 merc electrical problem

hey guys,my 170 merc i/o has no voltage at the coil when the ignition switch is on.Could it be a faulty ignition switch or is it something else.It starts and runs fine with just a little backfiring if you put the thrott down to fast.Any thoughts would be a big help.

That can't be. If it had no voltage to the coil (+) from the ignition switch, it might start, but would die as soon as you released the switch back to run. Check the coil voltage while it is running.

 

[lewski]

Re: 170 merc electrical problem

it has 0 volts at the coil whether the ignition switch is on or not...tried measuring it while it is running but my voltmetre jumps all over the place...it is unreadable...very weird....shouldnt it read about 9 volts just befor the engine turns over ...thanks

 

[Eric 3.7LX Alpha 1]

Re: 170 merc electrical problem

Your black test lead doesn't go on the (-) terminal of the coil, it gets grounded to the block somewhere.

 

[blueagletalon]

Re: 170 merc electrical problem

u might have a bad starter selnoid. i had the same problem and it was mine.

 

[stonyloam]

Re: 170 merc electrical problem

Your black test lead doesn't go on the (-) terminal of the coil, it gets grounded to the block somewhere.

Agree.