Ignition Help - Rich?

[Tonka Jim]

My '68 V174 with the 120 Mercruiser (GM 4Cyl) started acting up last Saturday.

When in run mode - power to the coil.
When in start mode - no power to coil.
You can turn starter over all day but it will not fire until you let go of the key to run.

[75starflight]

Sounds to me like the solenoid that powers up the coil during starting could be giving you fits. We have that happen all the time with what i would call a cab power solenoid on our older 71-89 series CaseIH Magnum tractors. I think this because when you are in the run position that solenoid is by-passed and the power is coming direct from the switch.

[Rich_V174SS]

Yes, when you're cranking the engine (start mode) power to the coil should be coming from the starter solenoid. Check your wire terminals for looseness or corrosion, bad connections etc., but the problem could be in the starter's solenoid, not making electrical contact when the solenoid engages.

[Tonka Jim]

Thanks Guys,

A new slave solenoid and a few new wire ends and I'm good to go!

[75starflight]

Glad to hear it!