Tach signal problems

[bob johnson]

my tach seems to work in neutral up to at least 3000 rpms, but under power it runs up to about 2,000 rpms with the motor , then falls off back to between 1000 and 1500...even while the engine RPM s catually continue to increase.

the mechanic mentioned it might be in my regulator -alternator....but not sure what i am looking for...

it is a 12 pulse motor he says 6 plus 6 minus.

i have the tach on 6P

I really want to check WOT rpms..but cant till i solve this tach issue.

I posted obver in OMC forum, because the motor is an Evinrude

1997 90 hp 2stroke

60 degree optical ignition system

thanks

bob