Rectifier Regulator Assy 6S8-81960-00-00 fails blows 20A main fuse on FX HO 160 MR-1 engine

[84rzv500r]

Had a Main 20A fuse fail on the starboard engine last night after sunset when started up to come in... keyswitch normal fuel pump normal starter relay normal and it made about one engine revolution before it popped the fuse replaced the fuse and turned on the fuse blew again... so pulled the stbd fuses and fired up the port engine and cruised the 5 miles home in the dark at 7-8 MPH cranked up the stereo and sipped on a cold silver bullet... so to trouble shoot today.... disconnected the starter still blew the fuse at bat on... consulted the schematic... and my as built schematic... all good but Neg side of fuse goes to starter relay and shares the post with the hot wire from the rectifier/regulator... unpluged the rec/reg no direct short put in a fuse and powered up all good... so I dug out a used OEM rec/rec reg from spares...

The $161 question:

Was this infant mortality on an aftermarket rec/reg? a thing with SCR rec/Regs with LiFePO4 batteries or a sign to convert to a MOSFET rec/regs?

I think ill put a used known good Rec/reg in my tool box on the boat...

 

[Ronnie]

Covid pricing still in effect or simple inflation? I don’t know if this helps but I replaced the rectifier on my 2006 fx Waverunner for about $100 in 2015, the motor (992 cc mr1) had about 300 hours on it.
when it was going bad the ski would start cold but sometimes cranked longer beforehand and eventually the motor would die sometimes a few minutes/feet out other times over an hour/miles out and it would not restart again for hours.

 

[FSH 210 Sport]

How old was the reg/rec?

Are the pics of the two reg’s different units? One looks to have some deposits on it and the other does not.

Judging by the pictures the air flow could be restricted with that wire loom laying up against it? The late model reg/rec’s are mounted to a plate that is water cooled.

As a fyi the charging systems on our boats are always at full output with reg / rec’s shunting unwanted power to ground.

On my boat the main fuse is a 30A fwiw.

If you’ve got spares (OEM?) I’d run one of those and see if that holds up, probably just a bad unit.

What are MOSFET units?

 

[VitaminSea]

Last year I had a rectifier go on my 2012 SX210, MR1 (non-HO). I kept getting battery warnings, turns out the voltage was high. Probably had around 250-60 hours on it. As @FSH 210 Sport mentioned, mine is mounted to the engine block.

Glad you were able to make the best out of the situation and enjoy the cruise back in.

 

[84rzv500r]

No issues for 6 months. my gut feeling is that it was a premature failure.. though I've added an entry in the logbook and will monitor... Im talking to a company on NH that has uprated SCR and MOSFET units to see if they will make a MOSFET unit that is plug and play (the universal MOSFET units require changin the plug... (i know after building and integrating the 4 strokes into a 2 stroke boat it seems silly but I tried to keep everything OEM connectors and compatible)

Regs were new $29 Chinese when the engines were installed (service date 06/22).. I have have 2006 vintage OEM units off the dead ski and pile o parts i got with it. I pulled one our of the pile to replace it and it worked fine (hence the scalies and that was cleaned up a bit).... Yeah I pulled the wiring back away a bit for better airflow.

SCR is Silicon Controlled Rectifier (run HOT) basically a full wave diode bridge out of P/N transistor material... MOSFET is Metal On Semiconductor Field Effect Transistor.. way more efficient (switching) and less heat and better voltage for LiFePO4 bats...

my boat has three fuses in the ECU box... 20A main that is starter and Bat/Rec/Reg, 3A fuel pump, and 3A that feeds the Ignition switch (fire suppression LED and Bilge fan) to light the ECU main relay on the STB and on the PORT it just feeds the Ignition switch to light the ECU main relay

5 fuses for the sound system load off the house battery buss

All other electrical load is on individual/like device Marine breakers... 20A main buss in the boat, 20A Aux Bus for big lighting and Radar 10A Buss for Aux Bilge pump, 30A for trim tabs... and the others are mostly 3, 5, 8A

 

[84rzv500r]

OEM Mfg of Rec/Reg

 

[FSH 210 Sport]

OEM Mfg of Rec/Reg

Thanks for that link! I can see why you are interested in the MOFSET type of 3 phase units.

I use to work with SCR’s in drilling rig platforms and VFD’s for downhole / submersible pump motor assemblies.

As mentioned previously, our alternators / chargers are PMG or permanent magnet generators, as such their magnetic flux / field density / rotor excitation is fixed so the output is always at full. In the explanation of the MOFSET units only the “short” version would be possible to use in our systems since there is no way the sensor of the “long“ unit could then control the flux density or rotor field excitation in our PMG’s, do I have that correct?

 

[84rzv500r]

ok so after digging a little bit Yamaha R1 Motorcycles and the 1.8L SVO and SVHO appear to have MOSFET style 30A unit... the connectors are different RICK's has a connector kit and std Voltage and LiFePO4 voltage version of this form factor... Im not going that way just yet however im thinking about it... Wiring Harness Connector Kit 11_115

@FSH 210 that looks correct to me the SHUNT to ground style work better with high freq AC.... EE classes were a LONG time ago for me and ive consumed a lifetime of beer since then ???

 

[FSH 210 Sport]

Awesome! Thanks for doing that homework!

Ever since attending a college EE class when I was 15 I’ve found electricity and specifically magnetic inductive generation and transformation just fascinating.

 

[FSH 210 Sport]

Question, how are the MOSFET reg/rec different from the SCR type in how the unwanted generation is dealt with?

 

[84rzv500r]

Question, how are the MOSFET reg/rec different from the SCR type in how the unwanted generation is dealt with?

see the schematics link above... they shunt unneeded current to ground...

 

[FSH 210 Sport]

Thank you !

 

[84rzv500r]

At least the type that is in use in our boats...

 

[FSH 210 Sport]

FWIW, I always wondered years ago why the reg/rec was always so warm/hot on my dirt bike. It wasn’t until this last year that I understood how these reg’s work and that they are always at full output.