2005 Yamaha 175 HPDI Stator or Rectifier?

[Bminus]

Hello,
I believe either my stator or rectifier has gone out. My starting battery is not charging. I tested the A/C voltage coming from the stator and got 15V at almost every combination (green wires). I attempted to test the resistance on the stator, but my multimeter would flash 300ohms then drop to around 0.7ohms... I also tested the DC voltage coming directly off of the rectifier (ground and red wire) and got 12.6V not running and 12V running.
I have not had a chance to take off the flywheel to inspect the stator, and I'm having a hard time finding anything online as far as output specs for my motor. Anyone know what my output A/C voltage should be?

My tachometer seems to be working; however around a year ago it went from showing 5600rpm WOT to 7000rpm WOT. This happened after I had an extremely rough ride on Toledo Bend. At the time I attributed it to the rough water, took the tachometer out and turned the gain down so the readings would show closer to normal because the motor did not run or sound any different. Now I'm starting to wonder if that was because of part of my charging system was going out?
I only noticed the starting battery not charging in the past week though.

Any advice would be greatly appreciated.

 

[boscoe99]

Specifications are in the applicable service manual.

How do you turn down the gain in a Yamaha tachometer?

How are you seeing any voltage from the R/R when the motor is not running? Sounds like you have the R/R connected to the battery and you are measuring battery voltage and not R/R voltage.

 

[Bminus]

I don’t have the service manual.

Theres a gain knob on the back of the tach...
And you are correct. I guess I was just measuring battery voltage..

 

[Bminus]

I figured I'd give an update, just in case any one with the same motor happens upon this thread. I purchased the service manual.

The stator voltage should be 37 VAC at 1500RPM Minimum and 83 VAC at 3500 RPM Minimum iirc. My stator is working properly.

The proper way to test the rectifier is to unplug the output wires(red) from the fuse box and test the voltage (while motor is running) with the ground. They have a blue clip on them and both wires will give the same reading.
Unfortunately my rectifier gave a reading of 0 VDC, and all my wiring appears to be in good shape... So ive got a new rectifier coming in the mail.
Hopefully this will get my charging system back up and running.

 

[QBhoy]

Quick way of telling which. If the engine does not fire at all...it will be the stator (or other things). If it fires and runs for a while (until battery goes flat) and battery is not getting a charge, it’s the rectifier. The engine won’t get a spark if it’s the stator.
Most likely the rectifier and often the cause of which is jump starting the engine from a running car or boat with too high a current for the circuit of an outboard or jet ski. Should never jump start an outboard or ski from a running donor engine....not saying that’s what happened...but just a thought and the most common cause of a blown rectifier.

 

[99yam40]

the amount of bad info on this thread is amazing

Get a manual and follow the testing procedures

 

[boscoe99]

"The proper way to test the rectifier is to unplug the output wires(red) from the fuse box and test the voltage (while motor is running) with the ground."

Nope. The R/R output is tested with the system loaded. That is, everything is connected. The red wire should read battery voltage with the motor off. More or less 12.7 volts with a fully charged battery. With the motor up and running at a fast idle the output voltage should be nominally 14.5 volts or so. The battery is an essential part of the electrical system. Motor is not intended to be run without one.

 

[boscoe99]

Quick way of telling which. If the engine does not fire at all...it will be the stator (or other things). If it fires and runs for a while (until battery goes flat) and battery is not getting a charge, it’s the rectifier. The engine won’t get a spark if it’s the stator.
Most likely the rectifier and often the cause of which is jump starting the engine from a running car or boat with too high a current for the circuit of an outboard or jet ski. Should never jump start an outboard or ski from a running donor engine....not saying that’s what happened...but just a thought and the most common cause of a blown rectifier.

You may be thinking of a motor with a capacitor discharge type of ignition system. Which does not need a battery.

The HPDI uses a transistorized ignition system. Which relies on the battery for electrical power. The motor will run just fine with the lighting coil disconnected or inoperative. Until the battery becomes depleted of course.

 

[QBhoy]

You may be thinking of a motor with a capacitor discharge type of ignition system. Which does not need a battery.

The HPDI uses a transistorized ignition system. Which relies on the battery for electrical power. The motor will run just fine with the lighting coil disconnected or inoperative. Until the battery becomes depleted of course.

Usually won’t run without a stator. At least most if not all the old outboards and jet skis I’m used to.
It Will however, run fine with a broken rectifier...as long as the battery is good...until it’s depleted because of the lack of charge. As far as I’m aware.

 

[99yam40]

Problem is you are saying stator, which means different things to people.
there are lighting coils, charging coils,pulser coils, and probably other coils under the flywheel.
just exactly what are you calling stator

 

[boscoe99]

The HPDI will run just fine without the lighting coil portion of the stator. Until the battery goes dead.

There is no charging coil on an HPDI. But there is a pulser coil on an HPDI. Six of them actually. Motor might run with one of the six inoperative but not very well.

There is also a crank position sensor coil on the HPDI. Motor won't run without it.

There are many carburetted Yamaha models that will run forever without a lighting coil. They won't run at all if the charging coil is inoperative.

Generic information when talking about a specific model can be misleading. Will send the trouble shooter down the rabbit hole.