Alternator/Solenoid Issues

[Mikeflyme]

Been monitoring the forum since last June…very helpful and educational…SOLVED A LOT of issues, thanks in advance.
Have a 2000 Monaco Executive PLS FD with an ISM-500 Cummins RV with what appears to have a Leece Neville 200 Amp Alternator.
The alt appeared to not be charging the chassis (engine) batts as shown on the dash analog gauge showing 10.5 Volts only on a recent trip. Helitrope digital meter read consistently .3V - .5V higher than the dash gauge readings above.
The alt appeared to not charge while on a return trip recently, so I ran gen to get a charge to the engine batts...worked ok (12.2V), and then I shut gen off and gauge went back to 11.0 Volts...for awhile, but then it went then back up again to 12.0 volts without the gen, but never to 13.5, as desired.
This morning, I ran the engine and again I didn’t get any charging on the engine starting batts. Then I did the Lambert LP-415 Battery Maintainer Test procedure and all is OK with it.
After the above, I then changed out the 2 85-Amp continuous-duty solenoids used with the Cole Hersey Battery Isolator and the Lambert Battery Maintainer...
I then next checked voltage at the alt and it shows 13.4 now after the solenoid replacements and on shore power...so I shut off shore power and then the alt appeared to charge to 13.5 after a couple minutes with engine running after I “awoke” it by accelerating the throttle.
Could the solenoids I replaced with now solved my “no alt charge” problem from previous?
Also, after all the above I then noticed the alt belt had some play to it (one would consider it normal slight flex of ¼”, but I also could move the fan blade shroud cover 1/2" to and fro in the circle (engine off)...does this mean the bearing for the fan shroud needs replacement, or is it the bearing in the alternator?
If the former, can this be replaced without a rebuild of the alt? Since it's putting out 13.45V once the throttle was moved above idle...now. After noticing the ½” flex on the fan shroud, I then remembered a sound much like the “rattle” sound of older injectors, which now appears to also be coming from the alt area…probably from the alt fan shroud .
I suspect the solenoid replacements cured the “exciter” problem thereby activating the alt to start charging again, as this problem has been occurring intermittently until it finally really took a hard “no charge” situation for me to realize there was an intermittent alt charging problem.
This is a very expensive alt as it's 200 amp and I'd like to fix the fan shroud bearing ONLY, if possible.
Any thoughts and suggestions would be helpful an appreciated.
Also, any suggestions where to get this work done other than Cummins dealership?
I’m in SW FLA area.
Truly a GREAT IRV2 Monaco site!

[rrs-ase-evt]

mike, make sure that the batteries are fully charged and check the specific gravity of each cell. A alternator will perform much easier and perform better with fully charge batteries. Also you may want to remove the alt belt and spin the fan and pulley and listen for any bearing noise. A alt should prduce 13.2 to 14.2 volts at the battery, use a good digital meter to check this. Do you here any wine type of noise comming from the alt, this could be a clue also that the alt is bad or on the way, do you have a belt tensioner or does the alt have pivot points, just make sure your belt is tight.
Ron

[Mikeflyme]

ALt has pivot points as the belt is circular only...

The charge is now 13.4V at alt when engine running, so it appears the "no charge" situation has been resolved with the solenoid replacements, unless the alt is not putting out intermittenly...haven't found that possibility so far...here's hoping the charge issue is solved.

Thanks for the thoughts and comments.

Mike

[YC1]

Take the solenoids apart carefully and look at the contacts. This should confirm your problem. If you are careful you can clean the contacts up and put them back together to save for a spare.

You may also have simply cured a loose connection when you replaced them. Be sure you clean up an and all other connections in that area. Grounds need to be shiny and clean again. You can shoot rattle can paint over them after they are tight to reduce rust.

[Mikeflyme]

YC1, Good idea to verify it was the solenoid(s).

[lonestarace]

Mikeflyme:
The 2 solenoids you replaced are related to the "house" 12v system(salesman switch). I doubt they were your problem, although they do get old and need to be replaced/repaired every 5 or 10 years.

Chances are your problem is: a) bad connection(there are many), or b) loose alt belt. Always start the trouble shooting process with the cheap things you can do yourself and work toward the more expensive things that have to be farmed out.

Check/clean at connections at all your batteries. Check/clean all connections at the 2 battery cut-off switches. Clean/check all connections in the curbside high current electrical box. Check/clean all grounds.

After tightening the belt tension, check the alternator cable connection on the back of the alt. At the other end of the cable is the battery isolator(finned thing) which is a solid state unit that allows alt current to flow one way to both battery banks. I've never heard of a battery isolator being intermittent. They are either good or bad. With the engine running, with a digital voltmeter, check the voltage at the 3 battery isolator posts. It should be about 14.7 at the center(alt) post, and about 13.7 at the 2 outer posts.

Rebuilders, like http://www.texasindustrialelectric.com/relays.asp , can replace the bearing, etc.

We hope this helps?
Photo Note: The Lambert battery maintainer was bad so was replaced w/a Trik-L-Start in the upper right corner of the electrical box.

[Mikeflyme]

Thanks for the heads up Lonestarace, I talked with Steve at your rebuilder and pretty much concluded the rotor core inside the alt is the culprit...since the alt will charge sometimes then not after that...intermittently, which fits my problem.

Also the rattling sound is probably the bearing that the fan pulley rides on and also allows for the 1/2" of rotation of the pulley when at rest.
He indicated the fan has been known to sometimes explode off the alternator with this condition.

Located a rebuild shop locally to the tune of $300 and 2-3 hours turnaround.

Thanks for all the feedback everyone.

Mike

[rrs-ase-evt]

Yes I have seen front bearings come apart as you stated, that is why I suggested to spin the rotor and fan asembly while the belt was removed from the alternator,also the rotor was probably shorting to ground at times. Glad to hear you have a handle on the problem now, good luck and drive safe. Ron

[Mikeflyme]

I went to the rv in storage today. Fired the engine and the alternator went to 14.2 on both chassis and coach batts immediately for a while...After a few minutes, the reading went to 13.15V at the alt cable going to the battery isolator.

So the alt is giving intermittent charge levels. Also listened with a short hose to the alt and no noise from the fan bushing up front but the rattling sound was definitely from the middle of the alterantor.

So looks like a new alt is in order. $707 Ouch...

Had a local alt shop quotr me $300 for a rebuild, but I'm not sure the Leece Neville 200 AMP Model LN 4884 JB DUVAC alt with 4 wires can be rebuilt correctly by the local shop...I need to talk further with them before I pull the trigger.

[lonestarace]

Quote:

Originally Posted by Mikeflyme Had a local alt shop quotr me $300 for a rebuild, but I'm not sure the Leece Neville 200 AMP Model LN 4884 JB DUVAC alt with 4 wires can be rebuilt correctly by the local shop...I need to talk further with them before I pull the trigger.

Your alternator has a built-in voltage regulator. Maybe that is all that needs replacing in the alternator???

I hope you can find a shop that will "work with you", and not a shop that will "work you over".

Don

[slickest1]

I have had a similar problem and with mine I am sure it is the isolater. I replaced the alternator(it was bad) but after that it would discharge at an idle. When you reved it up it would charge and then go to discharge and back and forth until it warmed up.I sent the alternator back in thinking something was wrong with it and it tested fine. Mine is a leese neville as well but it is a duvac alternator which means it has another circuit that it runs. There is small terminals on the back of it other than the two main ones. There is a wire from the ignition to one of them, and another from the isolater, tothe alt. The repair shop told me there has to be power to both these terminals in order for the alternator to charge. I think what is happening with mine is the isolator is starting to fail and is causing no current back up to the alt. I have a new one ordered. Hope that is helpfull.

[lonestarace]

Quote:

Originally Posted by Mikeflyme So looks like a new alt is in order. $707 Ouch... Had a local alt shop quotr me $300 for a rebuild, but I'm not sure the Leece Neville 200 AMP Model LN 4884 JB DUVAC alt with 4 wires can be rebuilt correctly by the local shop...

Check this out. $260. Free shipping, no tax.
Heavy duty Leece Neville truck and bus alternators

We hope this helps?

[YC1]

Quote:

Originally Posted by Mikeflyme I went to the rv in storage today. Fired the engine and the alternator went to 14.2 on both chassis and coach batts immediately for a while...After a few minutes, the reading went to 13.15V at the alt cable going to the battery isolator. So the alt is giving intermittent charge levels. Also listened with a short hose to the alt and no noise from the fan bushing up front but the rattling sound was definitely from the middle of the alterantor. So looks like a new alt is in order. $707 Ouch... Had a local alt shop quotr me $300 for a rebuild, but I'm not sure the Leece Neville 200 AMP Model LN 4884 JB DUVAC alt with 4 wires can be rebuilt correctly by the local shop...I need to talk further with them before I pull the trigger.

I must be missing something. If the batteries were relatively charged up then those readings would not worry me a bit. The high voltage was to replace the initial large drain and then it leveled off to a normal sustaining rate.

[EngineerMike]

Mike-
1) you can check the solenoids w/out disassembly. Apply 12v to the coil repeatedly & measure resistance across the large contacts; if it varies radically, there are carbon deposits on the internal contacts that rearrange, and time for new solenoid or rebuild.
2) if you have the alternator rebuilt, have them put the diode pack on the outside for better cooling; alternator rebuild should last longer that way, less heat internally. Several high amp draw Alpines (Apexes) found this to be a good mod when doing a rebuild.