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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: johns4104 on March 22, 2009, 09:49:46 PM

Title: Charging and electrical questions
Post by: johns4104 on March 22, 2009, 09:49:46 PM
I rewired my coach from back to front. It is a 4104.
I have a 130 amp. Leece-Neville alternator.
Where should the signal wire be wired to.
Right now I have it wired to the front panel, hot when the run switch is on.
It does not seem to charger until the rpm is up a little bit above Idle.
The lights are kind of dim but when reved a little the voltage gauge goes to 14 volts and the lights get much brighter.

Also my signal flashers and hazzard lights work fine when the engine is off but at idle they don't seem to work.

Any Ideas or thoughts sure would be appreciated.
Thanks,
John, Not the Electrician, That was my dad but when he died he took all that information with him!
Title: Re: Charging and electrical questions
Post by: NJT 5573 on March 23, 2009, 11:09:51 AM
John,

Get the part number of the regulator or the alternator and I'll look it up. I don't see why you can't pickup right off the battery though or closer to the battery. It should not need to be hooked to switched power and should not draw any power if the engine stops...

Its probably not a trigger issue, just to low of RPM to make power. May be less noticable with a full charge on the batterys and likely will only change if you can spin the alternator faster at idle.

Try running a hot jumper wire from the battery to the flasher circuit and see if that is the problem, then go back and see where the circuit stops with the switch on.
Title: Re: Charging and electrical questions
Post by: bobofthenorth on March 23, 2009, 11:17:13 AM
I've got a Leece Neville as well and it too has to be spun up a bit from idle to get it excited.  I suppose I could belt it so it would spin a bit faster at idle but I don't see it as a major problem.  I also take my tach signal off the alternator so I know when it starts putting out and I just run the RPMs up a little until the tach comes to life.
Title: Re: Charging and electrical questions
Post by: johns4104 on March 23, 2009, 06:09:31 PM
alt. unit # 3725j Service parts type rj3725
9048 date code
130 amps and 14 volts
That's all that is on the tag.
My tach uses the alt. signal also.
I will try to rehook the flasher power and see if that makes a difference.

Thanks
John
Title: Re: Charging and electrical questions
Post by: Sean on March 23, 2009, 11:59:52 PM
John,

That's a very old part number.  L-N has no information on it on the web site.

However, I hunted around and came up with the following guesses, based on the military version of the same model, and the follow-on 4xxx series replacement.

This should be a three-wire model with integral regulator.  You should hook the + and - terminals directly to the battery.  There should also be an "IGN" terminal that should be connected to the master switch.

Specs say the unit will not produce any output below 900 rpm at the shaft.  You might check your pulley ratio and make sure the unit will be spinning at least that fast at idle.

Hope that helps.

-Sean
http://OurOdyssey.BlogSpot.com
Title: Re: Charging and electrical questions
Post by: johns4104 on March 24, 2009, 01:35:21 PM
The alternator is gear driven so I do not know the ratio without pulling it off.
So it is possible that it does not charge at idle, no problem.
And yes it does have the built in reg. just hook up the three wires, oh make it 4 one is tach signal.

it seems that my bigger problem is the signal/hazzard lights.
they work in all conditions, headlights on/off high and low beam, engine on or off
but not with the marker/park/tail/dash light switch on.
I tracked that down a little,  if i disconnect the tail/rear markers the turn signal and haz. work fine in all the conditions as above.
I check the draw and the 7 markers are 1.89 amps.
The tail lights are 2.8 amps and together it was about 4.7 amps.
I have a 14 gauge conductor running from the front pnl to the rear elec. panel.

I guess I could and a switch to turn off the rear markers and tail lights if i need to use my signals at night.!!! LOL!!!

any ideas ?
Thanks

Title: Re: Charging and electrical questions
Post by: gus on March 24, 2009, 09:34:03 PM
John,

I had a 150a LN alt and had the sensor wire hooked to the engine run switch. I think the battery will slowly discharge if you hook it to the battery directly. It can also be wired through a small "No Charge" light, there has to be some resistance somewhere in that circuit to keep it from discharging the battery.

As already posted, it won't charge at idle because the 671 idles so slowly. However, I never let mine slow idle for more than a minute or two anyway so it doesn't matter.

I now have a LN rebuilt 100a that has no sensor wire and I like it much better, it just eliminates that one circuit. It won't charge either at idle but it doesn't take much above idle to charge.

I had almost the same turn signal/brake/tail light gremlin a while back and finally found that my tail light wires were crossed, ground to 12v, to two of the four lights. All my four tail lights are wired as tail/stop. At one point the engine would stop when I used a turn signal or the brakes!! This blew my mind.

The best place to start on the turn problem is the elect panel at the rear next to the engine. If you don't have a wiring diagram I'll send you copies by email of ones I got recently from Dallas. You need this to find the problem because it shows the circuit terminal numbers. I solved mine by disconnecting all the tail/turn/stop wires and reconnecting them one at a time until I found the problem circuit. You've already done this so you're well on the way.

The 4104 turn signal switch also will shut off brake lights on one side if the turn lever happens to be moved a bit in that direction from center. This drove me nuts for a couple of years. People would tell me me my brake lights weren't working but when I checked them they were fine. I had been moving the turn lever a bit to one side to better see the gages and unknowingly shutting off the brake lights.

The headlight circuit is not connected anywhere with the markers and tail lights which are together. I've tried to figure out a way to connect the tails with the headlights but there is no way to do it without stringing another wire from front to back and that is a major job if done right.

Since the markers/tail/turn/stops are all connected you have a crossed up connection somewhere. I know how you feel, it took me days and days to run down that problem.

It is also possible that the turn switch is somehow crossing up some circuits but those things seem to last forever with no problems.

It is interesting that your alt is gear driven, most are belt driven from a pulley attached to the old generator gear drive position. My objection to a gear driven alt is that if the alt seizes some metal is going to fly from somewhere. With a belt drive all you get is a burned or thrown belt.

Let us know how it turns out.