BAC Forum

General Boards => Technical Support => Topic started by: Jerry Emert on September 11, 2019, 12:58:13 PM

Title: Another Charging System Question
Post by: Jerry Emert on September 11, 2019, 12:58:13 PM
Just as I was pulling off the interstate in my home town Monday I noticed, on the Aladdin, that my battery voltage was 11.4 volts.  Looked at the dash gauge and verified it read about 10 volts.  Assuming alternator then started wondering!  The generator was running to keep the central Florida heat at bay.   The inverter charger was on.  Shouldn't the BIRD have been keeping the chassis batteries charged?  House batteries looked fine.  Right now the chassis is reading 11.9, the house 12.5 float charging with a fault on the magnum remote that says "fault MaxRN."  I will go get some meter readings soon but curious what you experts have to say before I go brave the furnace to get the meter readings.  I have a BIRD and a Bigboy relay if that matters. Thanks in advance.
Title: Re: Another Charging System Question
Post by: Jerry Emert on September 11, 2019, 02:06:37 PM
Just finished checks.  Found some kind of connector near alt behind and to right that has come loose from a bolt on connection and looks partially melted.  That may be a clue!  There are three wires coming from the back of the alt in addition to the large red (11.89) and black battery cables.  One red and two white.  With ignition on the small red is 11.89 and one of the whites is 11.66, I can't get to the other one.  Checks in the battery compartment are as follows...  Chassis batteries 12.2 ignition off 11.9 ignition on.  House batteries 13.22. BIRD coach 13.2, ignition (with ignition off 0) (with ignition on 11.69.) Solenoid 0 with ignition on or off.  Bigboy relay left battery cable 11.8, right battery connection 13.22. I will attach pics (if it works.)  I will have to replace the melted connector but my feeling is that it isn't the problem but could be.  Ideas?  Thanks again.   
Title: Re: Another Charging System Question
Post by: Mike Shumack on September 11, 2019, 02:10:51 PM
Is this the Magnum remote you have? Is the "Charger On" light On?

Also, on the fault code, the manual says that fault is because the generator was "asked to run" for longer time then was setup for "max generator run time". So you need to go into the settings and increase the "max run time". And you need to clear that fault code or the generator will not auto-start the next time, according to the manual.

 

Title: Re: Another Charging System Question
Post by: Jerry Emert on September 11, 2019, 02:22:04 PM
Pics?  Maybe?  I posted pic of Bigboy and BIRD because I thought I read a post that said that you don't have both at the same time.  Probably faulty memory.
Title: Re: Another Charging System Question
Post by: Mike Shumack on September 11, 2019, 02:26:46 PM
The Big Boy and BIRD work together.

Title: Re: Another Charging System Question
Post by: Mike Shumack on September 11, 2019, 02:49:54 PM
Chassis batteries 12.2 ignition off 11.9 ignition on. 

Alternator is not putting out the correct voltage to charge the Chassis batteries.

Quote
House batteries 13.22. BIRD coach 13.2, ignition (with ignition off 0) (with ignition on 11.69.)
This sounds normal.  Voltage at the "Ignition terminal/wire" on BIRD is low because the Chassis batteries are weak.

Quote
Solenoid 0 with ignition on or off. 
You would only have power here if you press/hold the Battery Boost switch.


Quote
Bigboy relay left battery cable 11.8, right battery connection 13.22.
Since the BigBoy solenoid is not "closed" you are reading Chassis battery voltage on the left terminal (11.8) and House batteries on the right terminal (13.22).

I think the problem is the melted terminal at the alternator. Your alternator is not charging. 

From the picture it looks like a Leece Neville Alternator - can you confirm?

On the red wire where you are measuring the voltage, are you measuring the voltage on the side of the wire "coming from the wiring harness" or is it the side "coming off the alternator"?

I think the Red wire is the battery sensing wire and that is what tells the alternator to charge, and the white wire is from the ignition switch and is what engines the alternator. However the sensing wire is only needed (I think) on systems that have the Duvac style isolator. I don't believe it is needed on the BigBoy style setup. I'll research this some more. Maybe someone else knows for sure.

In the mean time, I would work on repairing that melted connection. Maybe you can cut the melted connector out and just splice the wires as needed back to the alternator terminals.
Title: Re: Another Charging System Question
Post by: Jerry Emert on September 11, 2019, 02:55:08 PM
Thanks Mike, all checks with ignition on were engine off.  I haven't tried to start it yet.  Thats next.
Title: Re: Another Charging System Question
Post by: Mike Shumack on September 11, 2019, 03:01:03 PM
The generator was running to keep the central Florida heat at bay.   The inverter charger was on.  Shouldn't the BIRD have been keeping the chassis batteries charged? 

The Big Boy/BIRD manual says when the generator is running the BigBoy is isolated (not closed). This is to prevent the Generator and Alternator from both trying to charge the chassis batteries at the same time. And the generator would only be charging the House batteries.

That makes sense, but I thought I read about others running their generators in similar situation (when alternator failed) to get home. Maybe those reports where for a non-BigBoy system.  So if you were to remove the "generator wire" at the Big Boy, the solenoid would close and both Chassis and House batteries would get charged off the generator (or you could hold the Bat Boost switch On).



Title: Re: Another Charging System Question
Post by: Jerry Emert on September 11, 2019, 05:16:55 PM
What I first thought was a connector was actually a melted fuse holder.  It has a 5 amp fuse in it.  The fuse is a little scorched but good and the wired end appears unmelted so probably not the issue but I guess that will get fixed first.  The fuse holder wiring harness is labeled engine fan.
Title: Re: Another Charging System Question
Post by: Jerry Emert on September 11, 2019, 07:15:52 PM
Replaced the fuse holder and fixed a loose connection on the red small wire leaving the alternator, probably the sense wire.  Chassis batteries now read 12.4 volts charging from the inverter on shore power.  Started the coach and still shows 10 volts on dash meter.  Attached is a pic of the alternator.  Is that a replaceable regulator on the top of it?
Title: Re: Another Charging System Question
Post by: Mike Shumack on September 11, 2019, 08:06:38 PM
Yes that regulator is replaceable. Can you see the model number on the alternator?

The one highlighted is the model that cam eon my coach (per Build sheet), but it looks like the regulator are all the same part number for this series.
Title: Re: Another Charging System Question
Post by: Jerry Emert on September 11, 2019, 08:10:14 PM
Another check.  Engine off voltage across chassis batteries is 12.2 volts.  Engine running 11.9 volts.  Alternator or regulator?  The regulator has TRANSPO 9000 HD on it.  The alternator says model 7613N along with a couple other numbers.
Title: Re: Another Charging System Question
Post by: Mike Shumack on September 11, 2019, 08:23:55 PM
Your engine running voltage is lower because you sucked some power out of batteries starting engine and your drawing some power for engine ECM. So you definitely not charging. There is no easy way to tell from my vantage point if the Alternator itself is bad or if the regulator is bad. I would suspect the regulator.

Most would take the alternator to a shop and have it tested and repaired at this stage. But if your cheap like me, and want to try a self repair, then changing out the regulator is not too hard if you have access (or you could pull the alternator to get access).

According the Leece Neville "test instructions" you need 12.4 volts at the alternator for it to charge (I don't know how strict that number is) but you may want to get the batteries charged up a bit before making any decisions.

Do you have Shore Power available? if so you can plug in and would charge the Chassis batteries back up (if the Inverter/Charger and Big Boy are working properly).
Title: Re: Another Charging System Question
Post by: Mike Shumack on September 11, 2019, 08:28:39 PM
Another check.  Engine off voltage across chassis batteries is 12.2 volts.  Engine running 11.9 volts.  Alternator or regulator?  The regulator has TRANSPO 9000 HD on it.  The alternator says model 7613N along with a couple other numbers.

That 7613N is a good number.

Title: Re: Another Charging System Question
Post by: Jerry Emert on September 11, 2019, 08:56:48 PM
I've found the alt on Amazon and NAPA.  The regulator doesn't seem to come up as easy.  I'll order new alt from Amazon for a Leece Neville and hope!  Thanks.
Title: Re: Another Charging System Question
Post by: Mike Shumack on September 11, 2019, 09:01:40 PM
That's a good plan. I have the instructions for replacing the regulator (and brushes) and its a little involved.
Some are switching to the Delco Remey 28SI alternator (its brushless) but unless you can get it cheaper (or faster) I don't know if it will make any difference.

Title: Re: Another Charging System Question
Post by: Mike Shumack on September 12, 2019, 12:28:10 AM
Another check.  Engine off voltage across chassis batteries is 12.2 volts.  Engine running 11.9 volts.  Alternator or regulator?  The regulator has TRANSPO 9000 HD on it.  The alternator says model 7613N along with a couple other numbers.

That 7613N is a good number.

Jerry, I forgot to mention. be sure the alternator you order (if ordering on line) has the correct mounting style.

On my coach the alternator uses a "pad mount" (mounts solid to engine), some engines have a "hinge" mount (a long bolt goes through the bottom that alternator can rotate on with a mounting ear at the top that you use to tension the belt). I don't know what style you have (I think it is pad mount) but in the photo I used from amazon that looks like a hinge mount - however it may just be a generic photo they used.

EDIT: Based on the photo you provided, you have a hinge mount style.
Good luck.
Title: Re: Another Charging System Question
Post by: Jerry Emert on September 24, 2019, 08:37:02 PM
The alternator was bad.  Replaced yesterday and all is well.  It looked like a very straight forward job but as with most things Beaver at least of the early Beaver/Monaco hybrid, it was not!  It came off pretty easy but the bottom long bolt would not come out enough to remove.  It was hitting what appeared to be a support that ran from one side of the engine compartment to the other.  When I removed it the whole engine compartment seemed to shift just a little bit.  The holes for the brace/support no longer matched up.  Saved for the end but basically I lifted the coach on the left rear leveler until I could get the bolt in far enough to use the threads to help it in.  Easier than I thought it was going to be!  Clearances are tight at the back of the alternator, be prepared to reroute wires and connectors!  Last but not least, every wire and connection back there literally fell apart and had to be rebuilt, With my background in electronics I was almost happy to see something that I was familiar with finally!  Anyway it's back to travel ready!  Leaving in a few days to get out of the last of the Central Florida heat until November.  Next is the bigboy and BIRD!  Not sure it's working right, engine batteries were almost dead while plugged in to shore power. But problem for another day.