What THE ? 3.0 Dies After 20 Minutes

[Ksch439928]

I have a 1988 Four Winns 160 Freedom with a 3.0 L OMC Sterndrive . I myself am a mechanic but before I continue to diagnose this issue please let me know if you have dealt with this. After about 20 minutes of run time the coil is being robbed of voltage. I can connect a direct jumper wire from the battery and it will run. The coil and wire resistor all "check out" to be good. Components such as the interrupter switch seem to be functioning properly. Resistance / corrosion somewhere in the electrical system ? I know the Trim assist and solenoids are likely culprits . Sure would appreciate it if anyone has dealt with this issue. Not to mention a MEGA time saver.
Thank YOU !

 

[SkiGuy1980]

One of the engine guys may have a better hook... but I'd verify the ground first.

 

[alldodge]

Not an expert with OMC but the key switch has (according to manual) more than 3 terminals, so it has more then one feed for 12V power

Ignition switch is heating up and breaking connection.

 

[Ksch439928]

Yes I will definitely check the Key switch. I had that floating around as one of my probable causes. It would't hurt to replace it seeing how its the original one. Thank You Very Much !!

 

[Ksch439928]

I will most certainly check the ground . Thank you for your reply and suggestion .

 

[alldodge]

Yes I will definitely check the Key switch. I had that floating around as one of my probable causes. It would't hurt to replace it seeing how its the original one. Thank You Very Much !!

Had to put on the heavier glasses to read the small type, but also made it larger

 

[alldodge]

Yes I will definitely check the Key switch. I had that floating around as one of my probable causes. It would't hurt to replace it seeing how its the original one. Thank You Very Much !!

Had to put on the larger glasses to read, but also made it larger

 

[PITBoat]

I will most certainly check the ground . Thank you for your reply and suggestion .

I tore the dash up in an old Caprice police car once looking for the offending component relating to why the blower fan wouldn't run. It turned out to be... a loose ground wire under the dash on the passenger side. If you think that didn't stink... well it did. They probably pulled the cop stuff out of it before auction, and didn't bother to tighten the ground wire back up very good.

Shoulda kept that car. Gave it to my mother in law and she ruined it, lol.

 

[kenny nunez]

Try connecting a volt meter to the + side of the coil and run the boat until the problem starts. If the voltage is still in the 7.5-8.5 range then the resistance wire is still good. From what you are describing however, it points to the resistor wire. It is enclosed in the engine harness and covered with tape. Be sure to only use genuine Delco points and condenser as well as the rotor and cap. NAPA is also a good source.