Alternator Issues 99 Windsor

[twinboat]

Originally Posted by Mike Canter

I read an interesting article that gave another big reason for alternator failure on RVs and that was by running your house batteries way down while camping then not running your generator and getting out on the highway letting the alternator charge multiple dead batteries. This causes the alternator to overheat and blow the diodes and the high current across the brushes and slip ring causes massive pitting and wear. If the house batteries are run way down they said to run the generator when driving down the road to charge them up vice trying to have the engine alternator do it.

I have some reservations about the part of the article about massive pitting and wear. That kind of puts in question his research.

The current running thru the brushes of most alternators is around 10 amps. That's at full alternator output. Massive pitting ?

The output of the alternator does not run thru the brushs, only the regulated field current.

MH chassis are equiped with high output alternators so they can charge high input battery banks.

Pulling 150 continuous amps from a 250 amp alternator will not blow the diodes. Don't think you'll see more then that.

Reading up on some BIRDs, IRDs and other combiners, you will find that they cut in and out during high load conditions.

As the "dead" house bank pulls current from the chassis bank, that is being charged by the alternator, the voltage drops below the combiners "connect voltage" setting.

That's where the delay comes in. The combiner reconnects, after a set time, up to 10 minutes, giving the charging system a break of sorts.

This will repeat until the house bank comes up to a voltage high enough to not pull down the chassis battery.

IMHO, Running the generator will help quickly charge the batteries.

Is it nessessery, you be the judge.

[WindsorBruce]

Gentlemen, thank you for your replies and help.

My wife and I stepped out to attend a local car cruise in.

Twinboat, I will perform the checks you suggested tomorrow.

Guys, I am a motor head with basic mechanical skills. I am able to perform all routine maintenance, up to engine swaps (cars).

I consider myself fairly capable, but I lack a firm grasp of charging systems, particularly complex systems, such as our motorhomes.

Soooo, when I see terms and words, such as “BIRDs” “IRDs” “DUVAC” I scratch my head, and wish I knew and understood what the poster was saying.

It would be helpful to me and possible others reading, that these terms were explained

Also please see the photo below. Do I have any of the systems mentioned?

(sorry about the sideways photo, I am also "Keyboard Challenged"

[twinboat]

BIRD = Bi-directional Isolator Relay with Delay.

Connects chassis and house batteries together, when a charging source is detected from either alt. to chassis battery or charger to house battery. Once connected, either charging system sees 1 big battery. The delay is to stop rapid cycling.

IRD = Isolation Relay with Delay.

Only connects chassis battery to house battery when alternator is charging it. Same reason for delay.
No chassis battery charging with charger on.

You don't have these kind of systems, Yet.

You have a Battery Isolator.

It electronicly splits your alternators output to chassis and house batteries. Your house battery charger will not charge your chassis battery.

There is no delay needed because only the chassis battery controls the alt output.

It don't know how low the house battery is. Diodes loose 1/2 a volt thru them so your house battery never gets 100% charged while driving.

Duvac = The type of alternator you originally had. It has an internal voltage regualtor with an external voltage sensing terminal. This is needed to bring battery voltage past the one way diodes in your isolator system.

Most alternators can be converted but a better fix is to change to a BIRD system. Makes finding replacement alternators easy.

[Mike Canter]

Twinboat, I understand what you are saying but read what Monaco wrote as a NOTE at the bottom of the page below.

[jimbo2013]

Been thinking about up grading my relay system from the Trombetta & Intellatic to a Precision circuits unit

Here's a note from tec support

Our 00-10021-000 Battery Isolation Manager connects both chassis and coach batteries together into one large battery bank with either Chassis or Coach having a charging voltage. However, because they might be different types, we only connect if the battery is below 12.6 volts, needing to be charged, and we only charge for a maximum of 1 hour to ensure it is not overcharged. If the battery falls below 12.6, we will charge again. Our BIM's mission in life is NOT to fully charge batteries, but to make sure batteries do not go dead.

More detail in this post

[twinboat]

Mike Canter,

I know what your saying and get it.

I think the real issue is 12 volt system managment.

Keep your batteries above 50%, keep the belts adjusted and clean the engine occasionally.

If you are a fulltimer on the move, you will wear out your alternator.

If your an occasional RVer, corosion will get it.

If you neglect your batteries to death and need a jump start every time you pull it out of storage, your going to cook your alternator.

Anybody notice that the OEM alternators last longer the rebuilt.

[Papa_Jim]

Anyway.

To get back to the OP's dilemma.

I had this similar experience with our coach years ago, and it took me a long, long, long time to solve.

From my experience, if any wires that were connected to the original alternator are now not used with the new alternator, the new alternator will not work in the coach. The coach must then be rewired to adapt to the new alternator. Also, the new alternator must have an AC post to feed signal to operate the tachometer.

From my experience, my first really serious question to you is, do you think you could somehow manage to get your old original alternator back?

Jim

[twinboat]

Originally Posted by Papa_Jim

Anyway.

To get back to the OP's dilemma.


Jim

The post is wandering a bit but the OP did ask for some understanding of MH charging systems.

[ahicks]

A couple of thoughts. First, after having our alternator rebuilt recently, I was told that Leece Neville had updated the regulators and the one that uses the ignition switched "exciter" wire was no longer available.

Thankfully, our coach has the Bird system installed so the "extra" wire wasn't an issue.

After much experience with the diode type isolators, and after experiencing the relative simplicity of a system using relays (name your own poison here), I would use this as an excuse to scrap that diode type isolator without a second thought. A simple system can be installed to replace it easily with minimum expense. Fancier systems, like the Bird, are nice, but not absolutely necessary. In either case though, that exciter wire problem on the alternator would disappear completely.

Last, only after rebuilding our alternator did the cause of it's failure become apparent. Both battery banks were so old they would not accept a full charge. Maybe about 12.5v and that was it. This was enough to remain functional in our situation (never "boon docking" for more than a few hours), and volt meter readings were low, but OK. My thought is, this left the alternator putting out much of it's capacity pretty much most of the time the engine was running - leading to premature failure. In our case it was the internal voltage regulator that eventually shut us down. -Al

[twinboat]

Delco 28SI Series High Output Alternators

These 28SI series high amp alternators are the newest in technology and are a great retrofit for older vehicles. They will replace the older style units listed below with the same mounting and connections as the original units. The 28SI series alternators are capable of producing much better output at low RPM (idle). You can pick from the available amperages we have below. Please feel free to call us at (909) 794-1600 if you have any questions.

Replaces:

Delco 21SI, 22SI, 24SI (J mount and pad mount)Leece Neville 2500 - 2800 series (J mounts)Leece Neville 4800 - 4900 series (J mount and Pad mountMotorola*12V units*(J mount and Pad mount)

NOTE: Can be used on*applications with self-exciting, DUVAC (remote sense), and/or ignition triggered OE systems. Also has a tach terminal.

**
J Mounts Front and Rear Views

**
Pad Mounts Front and Rear Views


MPN:*28SI |*Brand:*Quality Power

Amperages Available:

160 Amp Max -- 110 Amp idle $295.00*
200 Amp Max -- 130 Amp idle $345.00*
240 Amp Max -- 150 Amp idle $395.00*
270 Amp Max -- 180 Amp idle $495.00

Mounting*Styles:

J Mount to replace Delco 21, 22, & 24SI*
J Mount to replace 2800 & 4800 series Leece Neville and Motorola*
Pad Mount fits all Delco, Motorola, and Leece Neville

Pulley*Options:

No Pulley*
8 Rib Serpentine add $25.00*
Double Groove V Belt add $25.00

Regulator Options:

Internally regulated (this is normal/original)*
Setup for external regulator add $50.00

Please give us your OE Alternator model so that we can make sure you get the correct unit:

Qualitypowerauto.com

[mel s]

Originally Posted by WindsorBruce

Thanks Mel s and jacwjames
You guys responded while I was responding to twinboat.
Here is some "food for thought" for others reading this thread.
FOLLOW YOUR PLANS !!!!
my "original plan" was to remove the alternator myself and have it rebuilt. I called my mechanic, only so i could get a referral to a "reputable" "quality" proven rebuilder.
I was under some pressure to get the job finished, due to a planed trip. Christmas was around the corner, and I knew my mechanic could use the money, plus he said he had one "ready" that would work.
First, I should have done the job myself.
Second, I should have, taken pictures of the old alternator, including the Mod.#, and the connections of the wires to the alternator. I did not do that, because I thought it might offend him, taking pictures while he was working.
But "What The Hey" I am the one paying for it.
So here I am, with a non working motorhome probably due to a dangling un-connected wire.

WindsorBruce
In '05, (at 101k miles), had a similar "alternator experience" when I left my coach at a shop in Louisiana to have the internal regular replaced in my Delco Remy 21SI alternator from which the sense wire terminal had broken/corroded off.

After a 2 week wait, (and a payment to them of $250), they said that it was "fixed", (however it was not charging).
I took it off myself and took it to an alternator re-builder.
For only $25 the re-builder disassembled my alternator... found that the other shop had broken one of the brush wires when they replaced the voltage regulator... replaced the broken brush... checked all of the other alternator components... reassembled it... and verified that it was working correctly.

I wish you luck fixing yours

Mel
'96 Safari, 145k miles

[WindsorBruce]

Hello gentlemen, I completed my Sunday morning family duties so now I can play. Wow! you guys have a ton of information to share thanks.

twinboat---- I followed your instructions, and checked the Isolator. It checked out fine.

I then checked the alternator, by using a jumper wire, from the center post of the isolator to the chassis post, and "HALLELUJAH" (good Sunday word) the alternator is charging. The Tach is working, and the Alt. warning light is off.

So gentlemen, does this confirm the the newly installed alternator is indeed a externally excited model?

And if it is, what post on the alternator, should the un-connected wire (exciter wire)be connected to?

[mel s]

Originally Posted by WindsorBruce

Hello gentlemen, I completed my Sunday morning family duties so now I can play. Wow! you guys have a ton of information to share thanks.

twinboat---- I followed your instructions, and checked the Isolator. It checked out fine.

I then checked the alternator, by using a jumper wire, from the center post of the isolator to the chassis post, and "HALLELUJAH" (good Sunday word) the alternator is charging. The Tach is working, and the Alt. warning light is off.
So gentlemen, does this confirm the the newly installed alternator is indeed a externally excited model?
And if it is, what post on the alternator, should the un-connected wire (exciter wire)be connected to?

WindsorBruce
IF your "alternator is charging", the "Tach is working", and the "Alt. warning light is off", why are you still trying to fix it?
Wondering
Mel
'96 Safari

[twinboat]

Jumping the isolator terminals gave the alt. some feedback. You turned it on.

Don't remove it while running, it could overcharge.