Electrical help (for a friend)

[Jim Crews]

I am trying to help out a fellow dock mate with a m90a he bought from a dude, and paid wayy to much money. Never has got it started and running. I am a shade-tree boat mechanic that knows the basics of troubleshooting with my Fluke and other test pieces. I bought a service manual and tried testing the electrical parts. Nothing reads within or even close to spec. The coils all test wayyy out (no spark obviously) the cdi doesnt read even close, mostly open. Does Tohatsu use anything special in the ohm meter world? It says test scale rx1k, so sounds normal.
anyone with some real-world experience, I could ask so questions, would be greatly appreciated.
dude is already $2500 in this old motor!

i

 

[pvanv]

You must use an analog ohm meter, with a battery of 3v or less. If your ohm meter uses 9v, you may have cooked the CD. Digital meters will not work for this. I use a triplett analog, but others are good, too.

 

[pvanv]

The recommended meter is listed in the Factory service manual. The aftermarket menuals are too general, and a waste of money.

 

[Jim Crews]

I was under the impression that Fluke’s only use .6v to measure impedance, but that is weird you cannot use a digital meter. I have a small analog meter that only takes 1, AA battery. Guess I can try that.
Does that apply for their spark plug coils too?
couldnt get a good reading out of those either.
jim

 

[pvanv]

Coil secondary will be Very high, almost infinite. If low, the coil is shorted.

 

[Jim Crews]

High voltage lead to b/w wire, Or to gnd?
high as in (how high)
I remembering the manual said, but I dont think it was out of the ordinary.

 

[pvanv]

Primary side is the wire. Secondary is the HT lead. Measure to ground.

 

[pvanv]

The Factory service manual shows that arrangement. Aftermarket manuals are worthless.