Coils draining battery?

[Zippy69]

I tried searching, but no luck.

So I hope someone can help. I just got a 1984 XVZ 1200 that supposedly runs great, but the coils are suspected of draining the battery. The bike has sat in a garage for a while, so I just got a new battery and am giving it a long slow charge. Meanwhile I am in the process of putting the bike back together. Any help would be appreciated.

[Dano]

Only way the coils can drain the battery is if the key is in the on position. Charge the battery, disconnect the positive cable, put an analog (needle) meter in series and if you get voltagfe flowing thru the meter then you have something on with the key in the off position. Remove each of the glass fuses till you find the one that drops voltage to zero. That circuit will lead you to your culprit.

[Zippy69]

Thanks. I thought that problem might be a drain elsewhere, so I will give that a shot after a full charge.

[bkuhr]

Only way the coils can drain the battery is if the key is in the on position. Charge the battery, disconnect the positive cable, put an analog (needle) meter in series and if you get voltagfe flowing thru the meter then you have something on with the key in the off position. Remove each of the glass fuses till you find the one that drops voltage to zero. That circuit will lead you to your culprit.

 

Also while preforming Dano's test, disconnect regulator-rectifier

[Zippy69]

Pulled the positive and checked between pos battery and battery side of solenoid. Got 12v.

Pulled each fuse and still had 12v. What would unplugging the rectifier do and where is it.

Keep in mind that I got this bike Wed and today is the first time I have even looked at it.

[bkuhr]

Meter needs to be set to measure milliamps, start with highest A or mA scale you have, with all fuses etc hooked up normal and key OFF, and if no or low reading, scale down. Disconnect + wire from battery and place red lead of meter on battery+, and black lead from meter on the + wire you disconnected.

 

If you truly have something ON when the key is OFF, you will have a meter indication of some milliamps, meaning current is flowing even when the key is off.

 

Then start pulling fuses, until you find the one when your meter indication drops to zero. This is the circuit causing problems. It is possible for multiple circuits to cause problems, and meter would drop 'a bit' for each circuit fuse you pulled. If this is the case, keep track of how much each 'trouble' circuit dropped. Need to start troubleshooting with the worst one first.

 

There are a couple of circuits that work directly off the main 40A fuse, ie:clock,hazard,audio,and rectifier. Of these the rectifier is a likely culprit as they can short out.

 

There is a wire harnes down low left side near footpeg with, I think, can't remember off hand, a 6 wire connector. It has 3 white wires coming from alternator and other wires from rectifier and bike. Opening this plug with take rectifier circuit off for your check same as above. Also check this connector for signs of over heating/melting/burning. It is common, but needs fixed.

 

Let us know what you find, and if you think helpful, take pics.

 

Looking at wire diagram I am wrong about which 6 pin connector for the rectifier. It is the 6 pin connector with 2 red, 2 black and 1 brown wire. The 3 pin connector with 3 white wires is the one that burns frequently, and comes from the alternator to the rectifier. The rectifier is mounted inside the left frame between the frame and the swing arm.

Edited September 5, 2010 by bkuhr
correction

[Dano]

[GeorgeS]

If its a Lead Acid, OEM type battery, be sure to consider that it could be discharging " Internally "

 

If you find nothing else, then fully charge the battery, and disconnect the POS cable from battery. About 5 hours later, take a voltage reading, with Digital meter.

 

Let it sit for a few days, then re-check the No Load voltage with Digital Meter.

If its discharging internally then the level will probably be down around 11.5 or lower.

 

If so-- the battery is toast

[Zippy69]

Brand new battery, fully charged. I unplugged the coils, rectifier, stator and just about anything I could find with a connector, but still pulling 12volts. Will keep searching, and sooner or later I guess it will rear it"s ugly head.

[bkuhr]

Something as low current as the clock will show 12volts in the manner you have meter hooked up. Need to measure for amps/milliamps, and find the high current draw, if you have one. Haven't mentioned yet that you could have a different problem such as alternator not charging battery, but due to your suspision of current draw with key off, this needs to be eliminated first.

 

Most meters have a different port for the red lead to hook into when measuring AMPS, and typically have a fuse in this port, and give no indication if fuse is blown. So if you have a zero reading, need to verify fuse before trusting meter. Best way I found to verify meter is to place red and black leads accross flashlight or 9 volt (low amp) battery and see if meter moves, yes meter ok, no check fuse or meter setup. Do not do this accross MC or auto battery or you will blow meter.

 

MILLIAMPS typically use same port as volts, and if volts meter works, milliamp meter should work, try flashlight battery again very quickly to verify meter.

 

The reason we start this test with highest AMP scale, is we suspect current-enough to drain battery, but have no idea how much, and with a meter set up for measuring amps/milliamps runs ALL the suspected current THRU THE METER. If there is too much current for the meter setup/range selection, the meter can be burned up/fuse blown.

 

Question how to use meter, check your documention, or send pic of your meter.

[dingy]

Just a note about checking amps. To check amps, the meter needs to be in series with the circuit. To check voltage, the meter is paralleled with the circuit. If you aren't sure about this, I could draw up a quick schematic to show how to measure current.

 

When you are doing an amperage reading, remove the positive lead from the battery. Hook the red meter lead from the meter to the now empty positive battery terminal, and then hook the black meter lead to any and all wires that came off the positive battery post.

 

To verify meter is functioning, turn the key on and turn radio on, you will see around a half amp or so reading.

 

Have meter set on high scale at first then drop down to lower scales.

 

Don't try the starter. Very few meters have a scale high enough to read the starter current without blowing a fuse. Starter will pull 100+ amps.

 

If you have the need to check the starter control circuit, disconnect the positive wire from the starter itself.

 

Gary

[Zippy69]

Checked the amps and got 500ma with everything off. Pulled fuses and all plugs again and no change. 500ma seems like a small amount to me.

Remember that this bike has not run in a while, so I am going on what information I was told. I'm starting to think it may be a charging issue instead, but I will need to get it running to check. I turned the engine over with the starter and everything seemed okay.

I will need to pull the carbs and clean them because I could smell the old gas.

[bkuhr]

500ma is 1/2 amp, and while not a whole lot, seems a bit high to me for the keep alive circuit of the clock, and even though other circuits are wired to 40A main, they should not be on and drawing any current. Seems to me clock should be in area of 5ma. Maybe you read/converted scale you were on incorrectly.

 

Anywho, I agree with you, and we need to check charging circuit when you get it running, and maybe come back to current with key off later.

 

Suggest keep battery unwired from bike, until needed, as 1/2amp draw will probable kill battery in under 1 week.

 

If you have plastic off, recommend keep it off until everything fixed, some connectors/dash/etc will be difficult later if needed, with plastic on.

[Zippy69]

No problem with the plastic being off, the bike came in boxes.

But my meter is a Fluke multimeter with auto ranging. I switched between ranges to make sure and it read .5 and 497-501.

[bkuhr]

No problem with the plastic being off, the bike came in boxes.

But my meter is a Fluke multimeter with auto ranging. I switched between ranges to make sure and it read .5 and 497-501.

 

Good meter,

Anyone else have idea correct key off current? Sounds like good test, now we need to decide if 1/2amp is to much to keep troubleshooting. I'll check mine tomorrow and post back.

[bkuhr]

Checked the amps and got 500ma with everything off. Pulled fuses and all plugs again and no change. 500ma seems like a small amount to me.

Remember that this bike has not run in a while, so I am going on what information I was told. I'm starting to think it may be a charging issue instead, but I will need to get it running to check. I turned the engine over with the starter and everything seemed okay.

I will need to pull the carbs and clean them because I could smell the old gas.

 

Alright, I checked my 83 strd and I got .567mA which is .00567A.

Are you sure your meter didn't read .5 on the mA scale? If you really have 500mA, then we still have a problem to find.

[Flyinfool]

I agree to .5A indicates a problem that you need to find.

If pulling all of the fuses did not change it then you have an even bigger problem because someone wired in stuff with no fuse.

 

While pulling fuses don't forget the main fuse or the other fuse panel that is forward and to the right and down from the main fuse panel.

[frankd]

1/2 amp is way too much. 1/2 amp would be 12 ampere hours/day. The battery is only about 18 ampere hours so it would be dead in a day and a half. On my Olds Sillohette mini van my battery was dead after a leaving it sit for 3 days. I measured a 1 amp draw (and remember a car battery is about 4 times the size of our bike batteries). I found that the door switch wasn't quite back to straight up and down which allowed the remote door unlock circuit to stay energized.

 

I agree with disconnecting the regulator (the plug with the red and black wires in it)--that will eliminate a leaky diodes in the regulator. I forgot to look what bike we're talking about (1st or 2nd gen) but if it has a trunk light that could be on==on my Mk II 1st Gen you can eliminate that by disconnecting one of the wires on the switch in the trunk. Also on Royales there is a 2nd fuse box just forward and right of the main fuse panel. Did you pull these? If it's not the regulator or the trunk light I'll look at the print and see what jumps out.

 

Frank

[frankd]

I just looked an see you've got a Mk I. No trunk light. Like the other gentleman (and I forgot to look at his name) said make sure we're talking about 500 ma, not 500 micro amps. You may want to take one of those small test probes with the light in them. Put it in series with one of the battery cables. If it lights, you have 500 ma, if it doesn't you have 500 micro amps.

 

Frank

[Zippy69]

I will double check the amp draw. I may have misread it, which is likely.

I"ll look for the other fuse box, but the bike is all apart and I did not see one, but I wasn't looking for it either.

Thanks again for all the excellent advice and pointers.

[bkuhr]

While you have your meter out and bike apart, on the assumption you may have charging problem, check your stator windings. If bad will need replaced, and what better time than when bike is already apart.

 

Stator windings are the 3 white wires in 3 pin connector mentioned earlier. Open this connector and test 3 white wires toward motor with digital OHM meter. (Your Fluke should be fine). Set meter on lowest ohm scale, short meter leads and see what meter reads, .1 or .2 ohms make a difference. Subtract this reading (lead resistance and meter error) from test readings.

 

Test each white wire to each other.

A good reading is .42 ohms +-15% @ 68degF. Lets round this off to .4 ohms.

.2 ohms is bad, don't ask how I know!

 

We can deal with possible bad RR(regulaor/rectifier) when you have motor running.

 

There are some ohm tests we could do to RR, testing rectifier portion only, but a good test only means part of RR good but regulator portion could still be bad. Best wait till running, then we can do proper volts checks.

[Zippy69]

Thanks. I will do this test this afternoon and post back results.

[Zippy69]

Ok. Checked the stator wires and got .5 ohms.

Is there a test for the rectifier that can be done without the bike running?

I hope to get the carbs cleaned out by this weekend and get it running to check the charging system out better.

[Zippy69]

Well, got it fired up, but the floats are stuck so its pouring gas out. Can't keep it running long enough to check the stator output or the rectifier. I guess I will have to pull the carbs and clean the needles. I hope to get some pics or a video up soon.

[frankd]

Also test the stator to ground. It's a 3 phase delta winding, and if one of the windings gets grounded it lowers output considerably. I've had 1 go bad on my 83 and now another on my 89 and both were grounded.

 

You can check the rectifiers in the regulator with an ohmeter. If you have an analog ohmeter you may want to use it on the RX1 range. If you only have a DVM, set it to the position for testing rectifiers. Disconnect the stator and measure from the 3 white leads that go into the regulator (leads from the stator) and the black lead (or ground) on the regulator--wuth the meter leads connected one way you should see a diode on all 3 stator leads and when you reverse the leads, you should read an open circuit. Then do the same test to the red lead ( or batter positive cable) and the white leads going into the regulator (stator leads). Again you should see a diode on all three white leads. On my 83 a couple of years after I'd installed the stator, my voltage we down. The stator tested good, but I had a rectifier open in the regulator.