Voltage regulator

[bossman]

Im hoping someone here can direct me as to what my problem is.Symptoms: Bike is 2000 mm been starting fine here at home, left last Wed. for road trip to Ark. Got as far as Amarillo Tx. Stopped for fuel would not start had to boost.Dealer just down the road battery 2 years old put new battery in no problem rest of day. Stopped at motel for the night could smell acid occasionally. Bike would not crank next morning. Put battery on charger (nearby gas station) started got as far as next fuel stop would not crank again.Called emergency road service,trailered bike to small bike shop,,in Conway Ark. By the way excellent people there. Warrentied batt. Installed another new batt. Cranks fine.Both places checked charging system said that it was. Made it to Judosinia Ark. Did not use bike till I left on Sat. Evey now and then I would get a whiff of acid. On last fuel stop on way home had to boost. Got home drove bike in garage would not crank.

[saddlebum]

Im hoping someone here can direct me as to what my problem is.Symptoms: Bike is 2000 mm been starting fine here at home, left last Wed. for road trip to Ark. Got as far as Amarillo Tx. Stopped for fuel would not start had to boost.Dealer just down the road battery 2 years old put new battery in no problem rest of day. Stopped at motel for the night could smell acid occasionally. Bike would not crank next morning. Put battery on charger (nearby gas station) started got as far as next fuel stop would not crank again.Called emergency road service,trailered bike to small bike shop,,in Conway Ark. By the way excellent people there. Warrentied batt. Installed another new batt. Cranks fine.Both places checked charging system said that it was. Made it to Judosinia Ark. Did not use bike till I left on Sat. Evey now and then I would get a whiff of acid. On last fuel stop on way home had to boost. Got home drove bike in garage would not crank.

A short test in the shop may not catch an overcharging sustem if it is a suttle one or intermitant. Put a volt meter on the battery and moniter charging, while riding. There are usually only two reason for acid smell. defective battery (eg: a bad or shorted cell in the battery) or overcharging charging system boiling the battery. Moniter the voltmeter while riding to see if at any time the voltage exceeds 14.8 volts.

 

Another quick simple check is with ignition left off, disconnect the ground cable from the battery. Connect one lead of the voltmeter to the neg post of the battery and the other end to the disconnected ground cable (an ammeter would be better for this but not everyone has one and the voltmeter will suffice). Reverse leads if the needle swings in the wrong direction or if using a digital it shows neg voltage. You should see less than 1/2 a volt, If it shows more, say as high as 10 to 12 volts you have a parasitic drain. Start pulling fuses one at a time until the voltmeter drops, this will indicate which cicuit is draining the battery. Put the fuse back in and start disconnecting individual items on that circuit to pin it down to the cause. Keep in mind that some items like the radio or othe on board electronics do constantly draw some power to maintain memory. Disconnet thier fuses to remove them from the equation.

Edited August 20, 2012 by saddlebum

[Flyinfool]

Start by charging the battery.

 

The charged battery should read over 12V.

 

Next thing to check is the voltage across the battery terminals running. It should be around 14V with the engine running at 2,000 rpm or higher.

If it less than 13.5 you have a problem in the charging circuit. If it is over 14.5 you have a problem.

 

If the voltage is good then you need to start following wires. Follow the big wires from the battery and take apart and clean every connection from the battery to the starter. Should be 4 connections on the positive side and 2 on the negative side.

 

Let us know what you find and we can go from there.

[Flyinfool]

A short test in the shop may not catch an overcharging sustem if it is a suttle one or intermitant. Put a volt meter on the battery and moniter charging, while riding. There are usually only two reason for acid smell. defective battery (eg: a bad or shorted cell in the battery) or overcharging charging system boiling the battery. Moniter the voltmeter while riding to see if at any time the voltage exceeds 14.8 volts.

 

Another quick simple check is with ignition left off, disconnect the ground cable from the battery. Connect one lead of the voltmeter to the neg post of the battery and the other end to the disconnected ground cable (an ammeter would be better for this but not everyone has one and the voltmeter will suffice). Reverse leads if the needle swings in the wrong direction or if using a digital it shows neg voltage. You should see less than 1/2 a volt, If it shows more, say as high as 10 to 12 volts you have a parasitic drain. Start pulling fuses one at a time until the voltmeter drops, this will indicate which cicuit is draining the battery. Put the fuse back in and start disconnecting individual items on that circuit to pin it down to the cause. Keep in mind that some items like the radio or othe on board electronics do constantly draw some power to maintain memory. Disconnet thier fuses to remove them from the equation.

 

It does not sound like a drain issue since it dead at each gas stop. It is either overcharging and killing the battery, or just not charging the battery in the first place. While it is possible, it is highly unlikely to have 3 bad batteries in one week.

[bossman]

Ok thanks. Am at work will tinker with when I get home. I now have a starting place. Thank you.

[saddlebum]

It does not sound like a drain issue since it dead at each gas stop. .

I agree, but it is a simple enough check to just eliminate the possibility, as remote as it may be.

[Rocket]

Evey now and then I would get a whiff of acid.

 

Sounds like battery being over charged & maybe even being boiled dry. That is normally the only time the acid can be smelled, due to extreme charge rates.

[GeorgeS]

Pull out the Rectifyer/Regulator Unit, Remove the Large Plug, and Inspect the

make and female pins.

 

I think your plug has been getting wet, from road wash, and you might have to replace, or re-build the Plug.

 

I know of at least 2 guys had to do this on 99, 2nd gens. And the R/R unit itself may now be damaged, if that plug has gone south.

[Gray Ghost]

There are a couple of stator checks you can make. Unplug the connector from the rectifier/regulator. Call the three white wires 1, 2, and 3. Check resistance (key off) between 1 - 2, 1-3, and 2 - 3. Yamaha specs say the readings should be 0.279 - 0.341 ohms on the three tests. The voltage at those points (still unplugged but with the engine running) should be between 15 - 100 volts AC. That is a generic standard.

 

You can check the rectifier by resistance checks at the R/R (key off). There are 6 terminals on the case. If the three that mate up with the white wires of the plug are at the bottom, the one that mates with the red is at the upper left. The ground wire is at the upper right. If you have a meter with a diode funtion, check between each of the three stator connectors and the R, then between each of the three stator connectors and the B. For the forward bias, you should get readings of 0.3 - 0.8 volts DC. In the reverse bias it should read OL. So if you don't have 6 readings of OL and six between 0.3 - 0.8 volts DC, you have a rectifier problem.