alternator/rectifier 140hp 1985

[SaltytSal]

I know that the rectifier part of this unit is on its way out- tach OK to 4000 rpm
-any higher it zero's out. The regulator part seemed to work fine until yesterday.
On the way back to the dock, the volt meter started to get readings between
14 and 16 volts. Naturally the higher the rpms the higher the spike. But for some reason it started to behave normal 13-13.5 once I got to the slip and manually
revved the engine from the throttle box. A friend told me that that the points
in these units sometimes stick. Is this true- as I do plan to eventually replace the
unit but would want to wait to do it in the off season. Thanks for your reply.

Sal Giosa

 

[wilde1j]

Re: alternator/rectifier 140hp 1985

You friend is clueless ... there are no points. The regulator/rectifier may be on its way out though. Consult the shop manual for tests to confirm before buying a new one.

 

[SaltytSal]

Re: alternator/rectifier 140hp 1985

Thanks Jim. Can this happen (sudden voltage spike to 15-16 volts) from time to time?

 

[wilde1j]

Re: alternator/rectifier 140hp 1985

I guess. Typically, they just crap out and fail to work at all, which the way most electronics fail. But there are intermittent and flakey behaviors as well.

I would check the stator AC voltage to the R/R and make sure that's solid before replacing the R/R. I would expect to see 30 to 50 VAC as fast idle across the yellows to the R/R.

 

[daselbee]

Re: alternator/rectifier 140hp 1985

The above advice it correct, including the part about points. If you do measure the voltage across the yellow stator wires at idle, please post back your voltmeter readings. I want to compare the readings with my own V6 readings. Please measure with the yellows connected AND disconnected. It will not hurt your stator to run it disconnected. Thank you.

 

[SaltytSal]

Re: alternator/rectifier 140hp 1985

Thank you all for your replies

Sal Giosa