Yamaha Tachometer Issue

[impalor419]

I have a 1989 Yamaha 130HP outboard. The tachometer is a digital multi function. Had the powerhead replaced with a remanufactured one last winter. After break in(few times out) e tachometer started acting funny. RPMs started bouncing up and down. Motor wasn't reving up and down, just the numbers on the Tach. Then it would work. The start fluctuating again. Did this a few times out, then finally quit. It is stuck on zero. Everything else works on tach. Trim and oil levels good. Oil alarm good. Just stuck on zero. Batteries are not charging. I have replaced the rectifier and did not help. Any help would be appreciated. Thank You.

 

[ClassicAQ]

The zero tach reading w/prior inconsistency sounds like a bad signal wire. Check the yam color code chart. I believe signal is green. Need to do a volt drop test to determine if bad wire is with the tach harness or main harness.

The battery issue is unrelated. If not charging then have it tested at an auto parts store. Probably needs replacing assuming its holding water in cells to appropriate levels.