165 mercruiser, inline 6cyl.

[519 charlie]

it's in a 1979 doral, was driving and it started to bog down. so I changed plugs , wires and a new coil. same problem, then it won't start so I changed the point and condenser, points were burnt bad, hooked up new points and when I turned the key, they fried too. what might be the problem? 165hp mercruiser, inline 6 cyl.

 

[makomark]

how long was the key ON before the new points "fried"? Mercruiser uses a ballast wire in place of a resistor...they usually fail open...so hard to say...

If the ignition is ok, I'd suspect the fuel pump if it has any age on it....

 

[519 charlie]

fried right when the key was turned, never left the key in the on position, can it be getting to high of voltage?

 

[guyjg]

High current cooked the points. Take a close look at the engine wire harness for chafed wiring shorted to the ignition.

 

[519 charlie]

Went through all the wires and they all were good to the eye other than the neutral switch wire , which i changed. If the positive on the coil is grounded out somewhere, would that also cook the points?

 

[RicardoMarine]

How are you setting/adjusting the contact points?
You should be setting the contact points with a dwell meter. Point gap is an estimate only of correct dwell angle.

You may want to test the ignition coil.


Example values only

 

[519 charlie]

Thank you everyone for your help and knowledge, The positive wire on the coil was grounding out and causing the points to cook. Changed the wire and she fired right up and is running perfect. Thanks again from Windsor ON. THIS SITE WAS VERY HELPFUL.

 

[Bt Doctur]

your response dosent make sense. the wire on the pos side supplies the 12v to make the coil work.

 

[makomark]

2X...and if the description in post #7 was accurate, no current could have made it to the points...

 

[guyjg]

Changed the wire

No melted insulation along the resistor wire? Did you replace the resistor wire too? If you did that the coil voltage will be too high.