Mercruiser 3.0 140 starting problems

[Jim79]

Hey guys

I bought a 1986 four winns freedom 160 with a mercruiser 3.0 140. I replaced the starter spark plugs and did an oil change. It turns over but will not start. The positive battery terminal also arcs red when trying to start. Its a brand new battery. Im new at this but love to learn how to fix things I own. I have not checked for spark yet. Any help would be awesome. Thanks

 

[alldodge]

The positive battery terminal also arcs red when trying to start

I hope its not arcing, maybe its glowing red?
If it is arcing then there is a real loose connection, need to clean the post and cables both pos and neg to shinny metal. If is glowing, then there is a loose connection and same thing needs to be done.

Need a voltmeter to see if your getting 12V at the + side of the coil with ignition ON

How old is the gas?

 

[Scott Danforth]

After you fix the batter cable issues. Service your points (file, set gap, adjust dwell, set timing)

 

[Jim79]

Yes it arced red only on the pos terminal. Ill try your suggestions and get back to you. Thanks!

 

[Jim79]

Brand new gas to

 

[Jim79]

I also noticed this. Could this cause arcing? See the wire showing through the metal.

 

[alldodge]

Yes, and also that cable needs either replacing, or need to cut the lug off and install a new one. I'll bet there is nothing but corrosion under the lug

 

[Lightwin 3]

That one is shot. Replace. Also check the other cable at BOTH ends. Remove, clean, reinstall. THen start looking for spark.

 

[Jim79]

Thanks guys

 

[Scott Danforth]

the arcing is from shot cables. replace them. clean every connection (even on the new cable) with emery paper or scotchbrite to shiny metal, then seal with marine electrical varnish (Green, not red)

your ignition is points, you have to service them if they sit longer than a month or two

 

[kerberos824]

How much of a hassle was replacing the starter? I'm getting ready to do it on my 2003 Bayliner 175, but man does it look like a hassle to get in there and do any work. I guess a compact makeup mirror might come in handy. Or a dang snake camera...