1964? merc 500 no spark???

[diesel69]

Have the usual sob story, got used boat guy said it runs "it dont"
turns over fine but no spark. ser#1692302
any help greatly appreciated , wiring diagram would be great too just to make sure all is were its supposed to be.
Thanks.

 

[Boatleech]

Re: 1964? merc 500 no spark???

1964 looks like a good guess. Clymer publishes a manual that covers yours:

http://www.clymer.com/Book.aspx?bid=627&title=Mercury+3.9+-+135+HP+Outboards,+1964-1971

you might find one in a good library. Someone here might post a wiring diagram.

 

[MIKEY*2007]

Re: 1964? merc 500 no spark???

click on top thread stickey what model /click on maxrules / click on tec specs and there you have wire dia

 

[Laddies]

Re: 1964? merc 500 no spark???

If you remove the ground out wire from the side terminal of the magneto and still have no spark you will have to repair the magneto.

 

[thefairlaneman]

Re: 1964? merc 500 no spark???

Taking the magneto apart (not removing the magnet rotor) is simple I would remove the cap and take a look cause it may be just burned/dirty/out of adjustment points and nothing else. Be careful not to forse or break anything. If the points are just a wee bit too wide it wont fire,but if they are right on the money the mag will be "hot" and should throw a strong bright spark 1/2 inch. Of course you need to inspect the rotor /cap etc for cracks but alot of wear often doesnt keep one from sparkin.

 

[diesel69]

Re: 1964? merc 500 no spark???

THANKS SO MUCH EVERYONE FOR THE HELP.
Found the cap was cracked , points were rusted solid.
off to the parts store i go and then to the lake i hope.
thanks again.