1986 Mercury 35 hp charging/tach problems

[burns114422]

I've just replaced my flywheel, stator, trigger, rectifier, tach, and new Quicksilver control box (with complete wiring that plugs into motor under cowling)

Having said what I've replaced, My battery still isn't charging, and my tach still doesn't work!!! Any ideas????

 

[Sunfish12]

Re: 1986 Mercury 35 hp charging/tach problems

I'm wondering if you have the battery charge wire and the tach wire switched on the rectifier?

 

[burns114422]

Re: 1986 Mercury 35 hp charging/tach problems

Thank you for the reply, but I do have the wires on the rectifier hooked up correctly. I'm just at a loss on what to do next to get my battery to charge, and tach to work... I bought a parts motor a few weeks ago that just had everything replaced and gone through, then the auto oilier quit working and locked up his motor. So I have lots of spare parts. That's why I replaced everything that has to do with charging system. Sad still doesn't work.

 

[Sunfish12]

Re: 1986 Mercury 35 hp charging/tach problems

You need the manual for the test for the stator charging wires and rectifier test.

 

[burns114422]

Re: 1986 Mercury 35 hp charging/tach problems

I have the manual, and have done the tests. I have done everything that I can think of, ran tests, replaced parts with the parts motor I have. I feel like its got to be something small that I've overlooked. The Tach pegs out when you turn power on at key, it stays pegged and doesn't move even after the engine starts. Static volts on battery also stay the same before and after engine starts. Very frustrating. The only thing that I didn't change under the flywheel is the "Trigger Plate", that plugs into switch box. Everything else under the flywheel, including the flywheel have been replaced. And rectifer, and the"8 pin" wiring harness from control box,Tachometer and control box have all be replaced. Results are still the same. Tach doesn't work, Battery doesn't charge. UHG!!! See my frustration.

 

[Sunfish12]

Re: 1986 Mercury 35 hp charging/tach problems

Disconnect the tach wire at rectifier and see if it still pins with key on.

 

[burns114422]

Re: 1986 Mercury 35 hp charging/tach problems

Yes, it still pegs with key on and grey wire removed from rectifier

 

[Sunfish12]

Re: 1986 Mercury 35 hp charging/tach problems

You have an issue with the tach circuit, I don't think it has to do with the engine. With tach wire still off, start engine and check voltage reading at battery and at rectifier charge terminal to see if you get different readings.

 

[burns114422]

Re: 1986 Mercury 35 hp charging/tach problems

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OK, I will try and get that test ran tonight when I get home. Just so I'm clear, make sure my stator wires are tight on their terminals (with grey Rachel wire off) start engine and test D.C. voltage at battery and again at (+) terminal of rectifier?

What does it mean if I do/don't get same/different readings? Bad rectifier? Or something else?