what exactly happens when the rectifier goes bad

[MAW31]

i used the reeves test to determine if my rectifier was bad.

sure enough, one of the yellow wires is 'open' in all directions.

what exactly happens when the rectifier goes bad?

for clarity, i've got a 88SPL, the rectifier is connected on the starboard side of the motor, just in front of the powerstrip.

 

[jonesg]

Re: what exactly happens when

Re: what exactly happens when

Fried the diodes.
Diodes only let current flow in one direction.

 

[MAW31]

Re: what exactly happens when

Re: what exactly happens when

thx jonesg, but what is the downfall of not having a working rectifier.

i figure mine's been dead for a while, yet aside from an occasional shutter, would be hard pressed to say anything is wrong.

like...what is the rectifiers job.

 

[Vic.S]

Re: what exactly happens when

Re: what exactly happens when

The rectifier is a network of 4 (3 wire types) or 6 ( 4 wire types) diodes. Making up a full wave bridge rectifier. (3 phase rectifier in the case of the 4 wire type)

If one of the yellow shows no circuit to the red or the case in either direction it means that the two diodes connected to it are blown.

You get no DC from a three wire type but you'll probably still get some output from the 4 wire type.

You dont say what year so have not checked to see if you have the 3 or 4 wire type.

If you have no Dc output the battery will not charge

 

[MAW31]

Re: what exactly happens when

Re: what exactly happens when

thx much VicS. Its a 1995. 3 wire. 1 red, 2 yellow.

I dont know that i've experienced a non-charging system though.

I'll certainly get it replaced either way.

Might it cause the motor to idle roughly, erratically?

 

[wilde1j]

Re: what exactly happens when the rectifier goes bad

No effect on running. Easy to check if charging. Start motor and fast idle (1200 to 1400 RPM). Measure DC voltage across battery terminals ... if >13.5VDC charging, otherwise no.

 

[ezeke]

Re: what exactly happens when the rectifier goes bad

What usually happens is that the diode burns out and simply will not work. What sometimes happens is that the diodes' wiring fuses in the potting, allowing the full battery voltage to flow into the stator and causing other problems.