Community Forums

jaminman · 08-27-2014, 02:58 PM

Ok, I have determined that I need a new or rebuilt alternator. From what I understand it would be a good idea to replace with maybe a 200amp unit. Any ideas? I have the Leece-Neville A001090875 8rg-20113 160 amps, I believe it is a J mount. It appears that it is self-exciting. It fits a Cummins ISB 5.9 300. Has anyone done a swap like this?

Dtwallace · 08-27-2014, 05:22 PM

If the upgrade is a necessity yes go for it. A rebuild shop should be able to do an upgrade if that can be done on the model you have. That would save you a bunch on a new alternator. If the regulator is not a built in unit, the rebuild shop should be able to help you with that also. As far as your present wiring, same thing. A good alternator shop is your best friend.
DTW

PyrateSilly · 08-27-2014, 06:06 PM

You may need to find out if you need to add something else into the equation. I know for us to go up we would need to add another part. We have it written down as to what from Cummins and Monaco what is needed but have not done that .... yet.

dennis45 · 08-27-2014, 06:15 PM

I just replaced my 160A Leece Neville with a direct replacement. The OEM went 70K miles so why mess with a good thing. In fact, the alternator could have ran longer but I misdiagnosed a problem with my BIRD system and replaced the alternator. I called Spartan for the P/N and then went to a local Auto Electric store and bought a new one. Spartan quoted $565 and the local shop was $429 (and that's CDN local Vs USD)

Air Baron · 08-27-2014, 06:26 PM

I just had a problem with my Leece-Neville 160 amp DUVAC alternator. Could not find a new one in Florida, found a place with a rebuilt for $179. Told the guy what it was doing...barely putting out 12 VDC. Both he and I felt it might be the voltage regulator. He told me to take it over to Lenz Auto Electric in Titusville, about 20 miles away. Called first, the guy said he could get a regulator and I would have it the next day. I went there, he dropped what he was doing, took it in the back room, tested it and told me it was the regulator. He found a new old stock heavy duty replacement regulator, put it in with a new set of brushes and charged me $55 plus tax. I was out the door within 1 hour. He told me that 99% of these LN alternators do not require a rebuild...and can be up and running with just what he did. He told me to hang on to mine and never turn it in as a core. It works like a champ.

Dr4Film · 08-27-2014, 06:57 PM

As I had stated in your previous thread, you are far better off having what you have rebuilt versus buying new.

It should cost less than $200 to have your alternator COMPLETELY rebuilt versus new at somewhere's between $500 - $1000 depending on the vendor.

RV engine alternators are wired differently than OTR trucks, buses and cars so unless you can find the EXACT model number with the same identical wiring scheme you are taking a big risk that it won't work.

Dr4Film ----- Richard

GA Navigator · 08-27-2014, 07:11 PM

I had a new regulator and bearings in mine for around $100-$150 (don't remember exactly) I removed the alternator and took it to an auto electric shop.

1994 Holiday Rambler Navigator
Cummins 8.3
Allison MD3060

Dtwallace · 08-28-2014, 01:21 PM

Richard,
would you please expound on you statement: ( RV engine alternators are wired differently than OTR trucks, buses and cars).

In my experience with automotive electrical system, any difference in this respect is only in the house wiring being added to the end result.

That has nothing to do with the original and purpose wiring of the alternator it's self.
Please educate me if I'm wrong because we all will benefit form your response.

DTW

Dr4Film · 08-28-2014, 01:57 PM

DTW,

I am by far not an expect by no means because I always have mine rebuilt versus buying new but I believe the biggest differences are the way the RV alternators have wired the exciter circuits versus other alternators.

I will check with some Monaco experts to see what they say. It also may be just a Monaco thing and not other RV brands,

I know Monaco commonly uses Leece-Neville alternators and that's what I currently have, 160 amp.

I have witnessed too many people who have purchased off the self alternators only to find out that they did not work correctly and it affected their voltage gauge also or it required them to do a rewiring job at the alternator to make it work correctly.

The best method is to have your old one rebuilt completely because you already know that it will fit the mount, wire up correctly and will work.

Dr4Film ----- Richard

mel s · 08-28-2014, 02:12 PM

Quote:

Originally Posted by Dr4Film

As I had stated in your previous thread, you are far better off having what you have rebuilt versus buying new.
Dr4Film ----- Richard

I agree

Trying to "improve" something that needs no improvement can open a can of worms.
Mel
96 Safari, 133k miles
original rebuilt 100A 21si alternator

Air Baron · 08-28-2014, 02:16 PM

I don't know anything other than what I have read trying to diagnose my problem. DUVAC alternators have 4 wires connected to them. Other than the large positive and negative, there is a wire from the ignition key. This wire probably runs thru a 5A fuse somewhere in the coach and tells the exciter to make voltage. The other wire senses battery voltage, or maybe even receives a signal from the ECU relative to engine RPM. I was told by one of the alternator suppliers that a standard alternator can be converted to a DUVAC.

Air Baron · 08-28-2014, 02:47 PM

Here are some pictures of the back of mine, prior to removal. Note the word DUVAC on the label. One of the small leads broke when I tried to remove it. The alternator shop had to cut the stud off with a Dremel and replace it. Heat and corrosion are not your friends.

I have also included pictures of the regulator prior to removal, and the replacement heavy duty regulator with cooling fins.

jaminman · 08-28-2014, 03:33 PM

I checked mine and it is self-exciting which means it has no ignition wire. It has + and - terminals and then there is a wire for the idiot light/alarm. We disconnected this wire and the alarm and light stopped. Coming in to the alternator is whatever is in the batteries and the same going out. It is definitely the alternator. There are people that have gone through many alternators with this model and that is why I am thinking of increasing the amps to 200amps. If there is any one that has done a swap over to the Delco 28si I would appreciate your comments.

Dr4Film · 08-28-2014, 04:07 PM

I looked through my archives that I keep on my PC and I found one Monaco owner that installed a Delco alternator in place of his Leece-Neville alternator.

I have copied/pasted what he had written below.

Erratic Tachometer:

The previous owner of my motorhome replaced the Leece Neville 160 amp alternator 3 times($$$) before I got it and soon after- it started pulsing (tach and voltage) again first at idle and then later on at all rpms. The MH initially came with an external regulator for the alternator and somewhere along the line, it was replaced with an internal regulator alternator and rewired.

The Leece repair instructions say to take off the regulator (on top of the alternator) and sand the tabs on the brushes and regulator with 600 grit sandpaper and this should eliminate undercharging, which it was doing. I did this and it stopped the pulsing and everything was fine for about 10K miles, then it started again and continued to get worse until I finally replaced the alternator with a 14.0V Delco 22SI ($100 new then). On my coach with the Leece- I had to pull the alternator out to work on the regulator so why not replace the darn thing with one I feel is better over all.

On my little coach, it was a direct bolt in, but I had to find information on how to wire it. I cruised the internet until I found a diagram on how to and it worked and put out 14.0 volts. BUT, since I had an isolator, the voltage was 13.3 (.6-.7 volt drop on each side of the isolator) to the batteries was not enough to charge them properly. So back to the internet and I found out that I could change the internal excited alternator to a external excited one by clipping a bus between the regulator inputs. Then I wired it thru a relay(energized by ignition on) to the output side of the isolator so the batteries would see 14.0 volts so it would charge the batteries better. I also found out that I could get a 14.6v regulator and could eliminate all the extra wiring and then later on I found out I could buy the whole Delco alternator with the 14.6 regulator installed.

If you have a Leece Neville 160 amp alternator is screwing up and have the mechanical and electrical ability to do this change - I would recommend that you replace it with a Delco 22SI. Why? Cheaper, Parts are everywhere, and it flat out works better in my opinion. I even picked up a spare in case this alternator craps out. I even carry tools and a spare tire because I hate to be at the mercy of some shop owner who lost their a$$ in Vegas and are trying to make it back from me. Been there.

It's been 10k+ miles since I made the change and not a flutter in the
tach or voltmeter.

Skip H.
32' Monaco Windsor
230+ HP B5.9

Dr4Film ----- Richard