F90TLR Not charging

[KW1720Tom]

I took the boat out for a bit this morning. When I checked the gauges at home the voltage showed 12.0 with the motor (2006 Yamaha F90) and all accessories off.

We put the boat in and were heading or when I noticed the voltage blinking 11.8 at me. No accessories running, just the motor. After a bit we stopped to eat lunch and shut the motor off. I switched the key to the on position without starting and the voltage read 12.0.

When I got home I checked the battery, which is brand new, and it's reading 11.99. I put it on a charger overnight. And the battery charged right up. It's reading 12.86v at the motor, battery and 13.0 at the gauge.

With the motor running on the muffs, 12.80 clear across the board.

What's the procedure to test the alternator /generator and the voltage regulator on this motor? I think it has something to do with a resistance reading.

[boscoe99]

Note the voltage at the battery before starting the motor. Typically it will be about 12.70 volts with a fully charged battery. Start the motor. The voltage at the battery should start to rise to more or less 14.6 volts if the charging system is working correctly.

You first check the R/R for output as noted above. If the voltage is below specifications, which appears to be the situation with your motor, you then check the lighting coil for voltage input to the R/R. If the lighting coil is providing the appropriate amount of voltage to the R/R but the R/R is not providing the proper output then the R/R is defective.

I am guessing that you will find the R/R is defective. But, please verify before buying and installing a new one. Have you inspected the R/R yet? This gizmo generates some heat and is air cooled. You might find evidence of over temperature and heat distress. Some might even argue that this particular R/R is problematic.

[melaatik]

Hi, If I remember correctly, my gauge shows about 14.4v when F100 EFI -06 is running. Sounds like that your charger in the engine doesn´t give charge.

Measure the voltage of the battery first before starting the engine and then when the engine is running. If there is no change, its evident that charger doesn´t work.

[KW1720Tom]

Regulator rectifier replaced and all is well in the world again!

The price wasn't too terrible. Genuine Yamaha MSRP is $151.99. The CDI brand one was $151.00. The dealer, did genuine Yamaha for $150 out the door. I know I could have saved a little by ordering here, but I'm taking the boat out tomorrow and needed it now.

And while I was there taking to the parts guy about my gauges being shot he said he's got a few used ones in great shape that he will sell me for half of what I've seen everywhere else! Going to take him up on that offer this weekend.