erratic tach 1995 175hp oceanpro

[angus63]

Three weeks ago my motor wouldn't crank. Found water got to the dual battery switch and connections oxidized bad. Cleaned and sealed switch and all seamed fine. Now my tach is climbing 1k high on it's own with the motorat constant rpm. Charge is steady at 14.75 vdc when above 1500rpm, and about 13.5vdc ati dle. When it comes to this type rectifier, can the tach signal take a dump and the charge remain fine? Checked gray wire connections and tach ground already. If it's the tach crappin out, is there a test for this? I have the factory manual. Thanks!!

 

[angus63]

Re: erratic tach 1995 175hp oceanpro

One other thing.....
Could the poor connections caused the rectifier to overheat (even though it's water cooled)and lead to this condition??
Is there a test for the rectifier tach circuit?
I thought it was low voltage AC?
Any thoughts?

 

[Chris1956]

Re: erratic tach 1995 175hp oceanpro

Angus, There is a test for the Tach circuit, as well as some tests for the voltage regulator. They are in the OEM Service Manual. In your particular case I would disconnect the connector containing the grey wire at the motor, turn the key on and see that the grey wire is not shorted to ground and doesn't have any voltage on it. Do the same with the purple wire, but make sure the connector containing the purple and red wires are disconected at the motor as well.

I really think that the water in your battery switch may have partially damaged the rectifier circuit of the V/R. You might check for AC voltage on the DC charging circuit. If you have AC going to the battery, one of the dioads in the rectifier is bad. You can test it at the starter solenoid since that is where the charge wire form the V/R connects.

 

[angus63]

Re: erratic tach 1995 175hp oceanpro

Thanks Chris
I will fuss with it on Friday


Are the charge and tach circuits independent of each other, or do they share any common inputs or outputs?

 

[Chris1956]

Re: erratic tach 1995 175hp oceanpro

Angus, The tach gets its signal from the AC side of the V/R(grey wire). The Charging circuit obvious gets it voltage from the DC side of the V/R(red wire to starter solenoid secondary). They are interconnected in that the control voltage to the V/R is on the purple wire which powers the Tach and the other gauges and accessories.

 

[ineedacottage]

Re: erratic tach 1995 175hp oceanpro

Angus63,

I have a different motor, but I believe this test by Joe Reeves will tell you if your regulator/rectifier is the problem or the tach:

water cooled regulator/rectifier test by Joe Reeves

It worked for me - I had a similar problem - tach wonky (eventually went dead completely) and charge was good, but it turned out the regulator/rectifier was the problem. Replaced it and all is good now (Thanks again Joe)!

 

[angus63]

Re: erratic tach 1995 175hp oceanpro

Thanks All

Borrowed neighbors tach
Still wonky above 1500 rpm
rectifier must be the culprit

CDI rectifier $155
sierra rectifier $215
BRP rectifier $299

Worth the risk going aftermarket????

 

[angus63]

Re: erratic tach 1995 175hp oceanpro

One other question....

How do I know I'm not chasing my tail and the stator is the reason for tach failure?

 

[Cricket Too]

Re: erratic tach 1995 175hp oceanpro

Angus, I don't think you'd show any charge voltage or tach signal if your stator went out.

Check the manual for the test for the stator and give that a check too, but I'd say if you test out your reg/rec it will show up bad. Even a loose connection will hurt it, so water and a lot of corrosion probably did it in.

P.S. I'm down in Lindy too, on the water by Indian Head Island. Just moved down there. PM me if you can help with any decent fishing spots, looking for something closer than the Inlet, hahaha. Thanks.