98 60hp Bigfoot wiring harness meltdown

[rayster008]

Any ideas what caused this? After about 10 mins. of running for the first time this year, my Merc burned the wiring harness from the multi pinned connector back to the various electronic componets on the engine as well as the positive battery cable from the solenoid back about 6 inches. Thanks for any and all feedback.

 

[Reloder]

Re: 98 60hp Bigfoot wiring harness meltdown

Probably a short

 

[CharlieB]

Re: 98 60hp Bigfoot wiring harness meltdown

Other than an obvious hot wire chaffing, shorting to ground and welded to the motor, an internal short in the rectifier is the most common cause fire in wiring. Once started the plastic insulation burns, dripping flaming blobs and rapidly spreads.

Replace all damaged wiring, either a new motor side harness or used, and replace the rectifier.

If the stator leads are damaged you may be able to repair them, but be sure to Ohm''s or DVA test the stator as a shorted rectifier could have cooked the charging coils in the first minute of the short.

 

[rayster008]

Re: 98 60hp Bigfoot wiring harness meltdown

Thanks Charlie. Further inspection revealed that the fuse holder, both trim/tilt relays and anything the pos. cable was near have also melted. Any suggetions on how to obtain correct part #s and where to purchase all needed parts?

 

[CharlieB]

Re: 98 60hp Bigfoot wiring harness meltdown

When all else fails, go here (have your serial #) to look up the factory part #'s

http://www.mercruiserparts.com/SelectProductLine.asp

The factor parts list is good to be sure you identify everything, have the correct #'s and get the sticker shock over factory prices.

For most of it I would recommend you Google used or recycled outboard motor parts to find marine yards, make phone calls to find out what you can get for at least half the cost of new parts. You may be pleased what you find and how much you can save over new dealer parts.