Re: Runaway motor with plug leads removed

[Casey Lynn]

Years ago I was sent in to visit and diagnose one of these engines. Probably late 70’s or very early 80’s.
The dealer was Vero Marine Center and the mechanic/service manager was Tom Council
The engine was a V6 crossflow 235hp.
Once the engine was run hard (we had a test wheel so we could duplicate it at the dock) the key could be shut off and the engine would continue to run.
Verified no spark at the plugs. Ignition shut off had grounded the packs as designed. Pulling plug wires made zero difference.
The owner of the engine had been running nothing but air-cooled two-stroke oil in the engine since new. He owned a small engine shop that sold lots of air-cooled lawn equip, etc.
Once the cylinder heads were pulled the amount of hard carbon build up was amazing. The engine dieseled on this pretty easily.
Once cleaned up the engine ran pretty good except for stuck rings. Repeated engine tuner applications were needed to free them.
Don’t remember how it all turned out except that the customer was raising Hell because I would not cover the repair.