Fire/WiresMelted/Trim/Tilt/Merc115/1985(?)

[jackc146]

Fire/WiresMelted/Trim/Tilt/Merc115/1985(?)
Any help appreciated !
This past summmer my Merc 115 outboard had a small fire. The cause I believe was a backfire or perhaps a disconnected plug from a helicoil. I'm not really sure as to why the fire started. The fire melted the Green, Blue, and Black leads togther from the tilt pump motor. The Black power lead became very hot melting external covering.
In and effort to repair it I have disconnected Black lead from Solenoid, along with Green & Blue wires. I applied power from Battery directly to trim motor by passing solenoid.. I placed repaired Black wire on positive, then blue on negative, resulting in sparks, I then placed green on negative again sparks. I left black disconnected from solenoid and engine started fine. I need some help in proceding forward. It appears theres a short but Im not sure where to begin. Trim motor stuck as is the owner.
Thanks for the Help
jackc146

 

[fisky]

Re: Fire/WiresMelted/Trim/Tilt/Merc115/1985(?)

hi jack on my 80 merc the black from trim motor is neg..blue pos+..green-neg....red to battery

 

[Chris1956]

Re: Fire/WiresMelted/Trim/Tilt/Merc115/1985(?)

Jack, Black wire is grounded. Power is applied to the blue wire (think sky) to run the trim motor in the up direction. Power is applied to the green wire (think water) to run the trim motor in the down direction. Therefore the solenoids should have a blue/white wire from the switch on the primary (small) connection and a blue wire on the secondary winding(large terminal). Same with green/white and green. The other primary terminals are grounded. The other secondary terminals are connected to battery voltage.

BTW - I find it difficult to believe your fire was from fuel and ignition. More likely the trim motor shorted or the battery cable insulation rubbed off causing a short.

 

[jackc146]

Re: Fire/WiresMelted/Trim/Tilt/Merc115/1985(?)

Thanks fellas for the quick reply. I attached Blk wire to negative ground and
when attaching either Blue, or Green directly to positive terminal I still get sparks. What would you suggest for next test.?
Jack

 

[fisky]

Re: Fire/WiresMelted/Trim/Tilt/Merc115/1985(?)

hi jack i got this off laddies check everything is connected right from the diagram

http://i236.photobucket.com/albums/ff254/fiskOZ/scan.jpg


fisky

 

[jackc146]

Re: Fire/WiresMelted/Trim/Tilt/Merc115/1985(?)

fisky thanks for pic. I have by passed solenoids completely.Chris has been very helpful with wire descriptions above. I ran a continuity check with and Ohm meter for what thats worth. I disconected black, blue, and green,wires from large secondary nuts on solenoids. I touched probes to green & Black no resistance. I touched probes to blue & black no resitance. My thinking tells me thats a circuit. However when I interface battery and connect blue to + to move up and black to - I get sparks. I'm guessing something in the motor is shorting out. Why the continuity though? I'm still scratching my head. Perhaps I need to look into sailing. HELP
Cheers

 

[fisky]

Re: Fire/WiresMelted/Trim/Tilt/Merc115/1985(?)

hi jack,sorry m8 i am not much of a sparky but what you describe,is 1 the trim motor is shorting,or you have a power wire touching the OB frame somewhere,try giving (laddies) a pm or move this thread to elecrical.sorry i am not much help..i would say its your trim motor..

cheers fisky

 

[MercFan]

Re: Fire/WiresMelted/Trim/Tilt/Merc115/1985(?)

From what I can understand, this trim harnass was the start of your engine fire. Somwhere it rubbed through.