1969 merc 500 ignition issues? might sound familliar?

[jtjt]

Re: 1969 merc 500 ignition issues? might sound familliar?

Anyone ever try to hook up a coil off an old V8 to one of these systems, it be easy enough to do and the systems are almost the same, distributor, brainbox/switchbox, coil, regulator/rectifier. why not? Most coils from that era are totally universal. It be nice to try out to see if it helps cause i got a few laying around.

 

[CharlieB]

Re: 1969 merc 500 ignition issues? might sound familliar?

Anyone ever try to hook up a coil off an old V8 to one of these systems....................

Don't waste your time, the input voltage to a Merc coil is FAR more than 12 V

IF it fired, it wouldn't last very long.

 

[merc850]

Re: 1969 merc 500 ignition issues? might sound familliar?

The rectifier on that engine is only part of the charging circuit it doesn't run the ignition, have you checked the cap and rotor for corrosion/water etc? If you remove the cap don't try to remove rotor from shaft it's molded on.
You can check the wires for shorts continuity etc. be advised that the wires screw into cap and the coil wire pushes in.

Typical wiring Dia.
There should be at least 9.5v at the white and red terminals of the four on the left.

 

[CharlieB]

Re: 1969 merc 500 ignition issues? might sound familliar?

It is a battery powered CD ign system and low or in this case high voltage will cause ign problems. If it runs it is not a switch box or trigger, that's crummy advice. High voltage on that system is caused by a bad connection or a light duty battery, anouther problem could be a dirty dist cap or worn cap brush.

When Laddies tells you something, you need to LISTEN,

 

[merc850]

Re: 1969 merc 500 ignition issues? might sound familliar?

Here are the specs and the wiring diagram for Lightning energized motors
and the test procedure
and values.

 

[Gomer50]

Re: 1969 merc 500 ignition issues? might sound familliar?

In my experience there is one most important thing that needs to be right before buying electronic parts(All the wiring needs to be in good shape starting from the stator down).A good Marine battery is a must.I have used the radio shack recitifiers with great success.Also very seldom have I seen a coil go bad ( I'am not saying its impossible).When I started with these motors I threw parts at them and pulled my hair out trying to get them to run right.When I finally got smart and invested in a new wiring harness first and put new wiring on my stators things began to get a lot easier.Not to argue with anybody but the trigger either works or it doesn't as goes for the switchbox.If I am not mistaken the battery must have at least 9 + volts to the switchbox or they wont fire.

 

[merc850]

Re: 1969 merc 500 ignition issues? might sound familliar?

Carb float setting
Lube intervals

 

[sutor623]

Re: 1969 merc 500 ignition issues? might sound familliar?

Carb float settingView attachment 137891
Lube intervalsView attachment 137892

Man, really good advice coming from you on this thread. You are slowly becoming one of my favorite go-to guys about this series motor. Goes to show that post count don't mean jack.

 

[merc850]

Re: 1969 merc 500 ignition issues? might sound familliar?

Thanks! even though I've been boating for 40 yrs. and been working on my own Mercs for that time I still use the manuals for the details.

 

[jtjt]

Re: 1969 merc 500 ignition issues? might sound familliar?

Man, really good advice coming from you on this thread. You are slowly becoming one of my favorite go-to guys about this series motor. Goes to show that post count don't mean jack.

i agree sutor623, thanks for pointing him out to me, ive been bugging him for a few days on pm and hes been good responding and posting all this cool stuff for us. Merc850 we bow to great knowledge, im not done bugging you though, lol! thanks.

 

[sutor623]

Re: 1969 merc 500 ignition issues? might sound familliar?

i agree sutor623, thanks for pointing him out to me, ive been bugging him for a few days on pm and hes been good responding and posting all this cool stuff for us. Merc850 we bow to great knowledge, im not done bugging you though, lol! thanks.

I know right! I put this thread on my bookmarks.