2004 F115 Regulator Rectifier Blows Every 12 Hours

[yamahaguy]

Cannot figure out why my motor keeps blowing regulator rectifier. Does anyone know what I should be looking for / testing for? Batteries are both in good shape and charging fully charged and charging. Test at 12.1v to 12.3v when boat is turned off. While running battery voltage waivers between 11.9v and 14.4v randomly, even when not using any added power.

Motor is hard to start cold and typically takes 5 or 10 tries. Idles okay but stalls out when I give it throttle, even when in neutral. Motor starts fine after being run / warmed up without issue.

 

[dingbat]

Batteries are both in good shape and charging fully charged and charging. Test at 12.1v to 12.3v when boat is turned off.

Your batteries are shot. A fully charged battery should measure 12.7 V when fully charged.

A bad battery will take out a regulator

 

[99yam40]

or a bad connection on the positive or neg side

 

[QBhoy]

Most likely that at least one or both batteries are buggered, I’m afraid. Long story short and in simple terms…if your a battery shows less than around 12.5v at rest…it’s not good news. I’d have a go at testing them individually. You may find that one completely gone battery is dragging the other down and the good one is giving the fooled impression that they may be almost ok. What you have described around when it’s charging and showing 9-14v…is a tell tale sign of a battery that’s duff. Worth a check anyway.

 

[yamahaguy]

Most likely that at least one or both batteries are buggered, I’m afraid. Long story short and in simple terms…if your a battery shows less than around 12.5v at rest…it’s not good news. I’d have a go at testing them individually. You may find that one completely gone battery is dragging the other down and the good one is giving the fooled impression that they may be almost ok. What you have described around when it’s charging and showing 9-14v…is a tell tale sign of a battery that’s duff. Worth a check anyway.

Both batteries actually sit at 12.5v after 24+ hours resting. Original post was after no starting / charging for two months. After charging both batteries are at 12.7v to 13v for at least first 12 hours of resting. All terminals and cables are connected properly, clean and corrosion free.

 

[yamahaguy]

Your batteries are shot. A fully charged battery should measure 12.7 V when fully charged.

A bad battery will take out a regulator

Both batteries actually sit at 12.5v after 24+ hours resting. Original post was after no starting / charging for two months. After charging both batteries are at 12.7v to 13v for at least first 12 hours of resting. All terminals and cables are connected properly, clean and corrosion free.

 

[yamahaguy]

Cannot figure out why my motor keeps blowing regulator rectifier. Does anyone know what I should be looking for / testing for? Batteries are both in good shape and charging fully charged and charging. Test at 12.1v to 12.3v when boat is turned off. While running battery voltage waivers between 11.9v and 14.4v randomly, even when not using any added power.

Motor is hard to start cold and typically takes 5 or 10 tries. Idles okay but stalls out when I give it throttle, even when in neutral. Motor starts fine after being run / warmed up without issue.

EDIT;
Battery voltage which I originally posted 12.1v to 12.3v was what I read on the tested after the boat sat for 2+ months without being run.

 

[99yam40]

that is not what you posted in the original post, so how can we help?
having 11.9 to 14.4v when running is a problem.
look for bad connections is all I have

 

[yamahaguy]

that is not what you posted in the original post, so how can we help?
having 11.9 to 14.4v when running is a problem.
look for bad connections is all I have

Yes, you are correct. In the original post I hadn't run the boat in 2+ months and the batteries were left connected. After I posted I ran the boat for 5 minutes and the battiest charged to 12.5 and 12.7 respectively. And now they have held these charges for 48 hours.

But yes, while its running the voltage indicator does fluctuate randomly and without added charge between 11.9 and 14.4v. That is still an issue. I assume this is due to the regulator rectifier being blown again. Which the motor seems to do every 12 to 18 hours of run time.

 

[99yam40]

from what I have read, bad battery connections can cause RR to fail.
wing nuts are frowned on.
see what you can find online and start you searching

 

[saltchuckmatt]

Wondering if your stator is freaking out ruining your rectifier....or your wires have a short. Something wonky here.

 

[QBhoy]

Sorry to ask…but have you jump started the boat recently? Doing that off a running donor engine can blow rectifiers easy.

 

[yamahaguy]

Sorry to ask…but have you jump started the boat recently? Doing that off a running donor engine can blow rectifiers easy.

I haven't jumped it.

 

[yamahaguy]

Wondering if your stator is freaking out ruining your rectifier....or your wires have a short. Something wonky here.

Yeah, its strange. I wonder if theres a way to test the stator?

 

[yamahaguy]

from what I have read, bad battery connections can cause RR to fail.
wing nuts are frowned on.
see what you can find online and start you searching

No wing nuts and all connections are clean and corrosion free.

 

[saltchuckmatt]

Yeah, its strange. I wonder if theres a way to test the stator?

Yes, but that starts to get above my pay grade. A good manual or YouTube video should get you through that.

 

[dingbat]

But yes, while its running the voltage indicator does fluctuate randomly and without added charge between 11.9 and 14.4v.

What "voltage indicator"?
Are you reading these voltages with a "gauge" or voltmeter?

Where are you taking these readings at?
Not sure how you get a reading lower than battery voltage with the battery connected?

 

[99yam40]

What "voltage indicator"?
Are you reading these voltages with a "gauge" or voltmeter?

Where are you taking these readings at?
Not sure how you get a reading lower than battery voltage with the battery connected?

this is one reason I suggested a bad connection

 

[yamahaguy]

What "voltage indicator"?
Are you reading these voltages with a "gauge" or voltmeter?

Where are you taking these readings at?
Not sure how you get a reading lower than battery voltage with the battery connected?

The voltage indicator on my Garmin. Just as an update I ended up changing one of the regulator rectifiers again (for the 3rd time in one year) and the motor is running perfect now, starts right up without issue and runs steady at 14.3 to 14.4 volts on the Garmin battery indicator. Guess we'll see how long this one lasts...

 

[yamahaguy]

Cannot figure out why my motor keeps blowing regulator rectifier. Does anyone know what I should be looking for / testing for? Batteries are both in good shape and charging fully charged and charging. Test at 12.1v to 12.3v when boat is turned off. While running battery voltage waivers between 11.9v and 14.4v randomly, even when not using any added power.

Motor is hard to start cold and typically takes 5 or 10 tries. Idles okay but stalls out when I give it throttle, even when in neutral. Motor starts fine after being run / warmed up without issue.

Just as an update I ended up changing one of the regulator rectifiers again (for the 3rd time in one year) and the motor is running perfect now, starts right up without issue and runs steady at 14.3 to 14.4 volts on the Garmin battery indicator. Guess we'll see how long this one lasts...