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Author Topic: Replacement 24V Alternator for MC5...8V71  (Read 6079 times)
NCbob
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« on: August 23, 2007, 11:11:42 AM »

I have searched the archives and most of the topics hit all around my search and none directly at it.
So here goes.....

It appears that my original engine (24v) alternator system has said goodbye.  Why am I not surprised?
It's only 39 years old...and the voltage regulator bolts rusted off at the mounting bracket so it's just sitting in that box and subject to all sorts of jolting.

It doesn't make much sense to me to do anything with this old system (the OTR A/C is long gone and the heat will soon be) and whatever parts I'd need are probably too expensive and unobtainable. So, I asked myself, "Myself, why don't we just replace the existing alternator with a late model alternator with an internal regulator?"  And I answered, "Hmm, perhaps the guys on the Board have done this so beating my head up against the wall doesn't make much sense....and it sure feels good when I stop!"

So fellas, that's my question..Is there a replacement 150-200 amp alternator out there for an 8V71 which will mount up in the same place as the old one without a lot of modifications and fuss and give me what I need to maintain the 24V Starting batteries and keep the 12V house batteries peaked up through the Vanner charge divider? That should be sooo simple for you more experienced techie's than me....please?

I'm not asking it to keep up with a lot of load...just occasionally running lights (on those rare occasions I get stuck driving in reduced visibility) or in the case of the 12V system...a small inverter to keep the fridge running and the headlights.

NCbob
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« Reply #1 on: August 23, 2007, 11:55:08 AM »

I doubt that you will find an alternator as good as the original 50DN. If the regulator is hanging on the wires you need to do some troubleshooting to determine if there is anything wrong with the alternator or the regulator or if you just have a wire problem.  Both the alternator and regulator are in common use and repairs are readily available.

It is not easy working in a MC-5 bay on the alternator and would be quite a job building a new bracket for a different alternator.

The common setup with a 24 volt 50DN is to run a 24 volt house battery and charge it with the 50DN and then use the Vanner Equalizer to provide the 12 volts needed for the house.
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« Reply #2 on: August 23, 2007, 01:20:17 PM »

Thanks for the comeback, Stan...I have determined that there is NO output to the batteries.  Now, too it could be one of the field relays in the driver's panel..just haven't gotten that far yet.

And yes, you're right. working around that regulator in a 5 is a PITA. The inside box would have to come off before I could get to the regulator mounting brackets and it looks like at least an all day job just to remount the regulator before I can see if there's any alternator output.  Not a job I want to tackle in August heat...but will snipe at it a little every morning.

There's certainly no one here in 'Podunk' who could repair the alternator should it prove that's the problem.
I'll just nibble away at all these little things and hope I can be ready for Kyle's Non-Rally in October.

NCbob
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« Reply #3 on: August 23, 2007, 02:15:29 PM »

Bob- the Delco 50DN is probably one of the best alternators ever made.  Being gear driven, pressure oil lubed, cooled with the oil, completely sealed, and no brushes, are very long lived-just look at the one you have now after 39 years!  I replaced my 50DN last year.  I have an advantage in that mine is a V drive and can get to the rear of the engine relatively easy.  The 50DN does weigh in at a heafty 100lbs.  I also installed a new digital regulator that regulates closer, but can still see the headlights go bright and dim a bit.  The digital regulator is about the size of a deck of cards and does have a voltage adjustment on it.  I have my regulator installed inside the bus to eliminate heat and dust.
I believe Leece-Neville made a direct drive alternator in the 150amp range that is more the size of a truck alternator.  Other than that, you'd have to install a pulley in place of the 50DN alternator to be able to run any of numerous belt driven alternators available.  A truck size alternator can be bought for about $250.00 new with internal regulator.  As compared-my rebuilt 50DN exchange with new regulator was about $1,900.00.  Just remember though-39 years of service is alot of time-compared to having to crawl up to adjust the belt periodically.  Good Luck, TomC
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« Reply #4 on: August 23, 2007, 05:04:28 PM »

The more I look at this, and more testing will come tomorrow morning, it might just be the regulator. I found the number on the Delco site but am having the devil's own luck in finding a parts house that might have a replacement.  And the beat goes on.......

Bob
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« Reply #5 on: August 23, 2007, 05:09:13 PM »

NcBob,
Good luck with the regulator, without the field voltage no output from the alternator.
TomC, you did great with a rebuilt unit for $1,900, The alternator was my first failure on my 5C, and the only replacement I could locate was NIB from MCI, @ $2,800 W/O tax. I thought flying maint. was high. I did find a used unit and replaced the shaft I needed for a lot less.

Gary
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« Reply #6 on: August 23, 2007, 05:12:38 PM »

Bob I have pulled and replaced the belt drive 50DN in my 5C and it is a bear. To modify that area and re injuner a different alt would be doable, but not easy. If your over the road air is gone you should have a spare space on your injun pully. It would be a lot less difficult to design and build a new setup back there someplace. I've seen that done lots of times. I'm sure many people would be happy to send you a photo of thier setup.
 I would diagnose the 50DN first!
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« Reply #7 on: August 23, 2007, 05:27:44 PM »

Jim, that's exactly what I plan to do in the morning.  The alternator should have enough residual magnetism to kick it off and I might be able to read a small voltage at the R terminal of the regulator to ground.  If I see anything (I use a Fluke digital meter) I'll feel better about the alternator.

Too, if I do find a voltage I should be able to excite the alternator (doesn't that sound exciting for an old man?) by putting even a small amount of voltage to the field wire. Normally it would take 24VDC to 'full field' it but it would prove to me that the field relays, both of them, are operating properly and the alternator is OK.

Ah, the pains we go through too keep these old girls working and looking their best! Huh

Thanks for the reply.....

Bob
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« Reply #8 on: August 23, 2007, 05:49:58 PM »

Bob: If your alternator is original, it should be a belt driven (4 belts) and air cooled which makes it easier to take out but in a 5 it is still a bear.

IIRC a 50DN puts out max voltage with about 10 volts on the field winding. If you disconnect the field wire (in case of shorted regulator) and hook your volt meter to the battery terminal it should show the battery voltage. Now start the engine and put a jumper wire between the battery terminal and the field terminal. If the voltage jumps up, the alternator is likely good.
 
If the alternator charges with full voltage applied to the field, temporarily connect the regulators three wires (battery, field, ground) to the alternator and try the engine again and see if the battery voltage rises. If that is OK then you are down to checking the wires and relays between the alternator and the regulator compartment.
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« Reply #9 on: August 23, 2007, 06:08:20 PM »

Hello Bob:

    If you need someone to repair your alternator and possibly get you a voltage regulator.  You need to talk to Phillip Hulsey at Star Auto Electric
in Cornelia, Ga.  telephone # 706-778-5656.  He is able to check yours and
tell you what's wrong with it and give you a close price.  I've seen him repair
big truck starters, down to motorcycle starters.  He can do it all, and a heck
of a nice guy.  If you need directions give me a call 706-778-five/zero/six/three.  Good luck.
                                             Glen Rice   
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« Reply #10 on: August 23, 2007, 07:39:22 PM »

Hey Bob,

I had a Guy in Greenville, not far off 385 in mauldin, rebuild/rewind my 50DN for about $800, if you take your regulater to him he can check/set it.  Mine alt is belt drive.  All the other alt shops in town said go to him.


also heres another thought

go bac where the AC was like the others said and use one of these

http://cgi.ebay.com/ebaymotors/Delco-Remy-24-Volt-Alternator-One-Wire-105-AMP_W0QQcmdZViewItemQQcategoryZ33573QQihZ018QQitemZ280143704102QQrdZ1QQsspagenameZWDVW

and get another one wire 12 v one for the 12 volt system.  find some nice chrome alt brackets from the hot rod section.  i believe you can hook the 24 v in there by the starter.

also maybe for the house batteries,  remember this thread

http://www.busconversions.com/bbs/index.php?topic=3160.0

and this? http://amplepower.com/products/genie

also from the truck places you can get a 175 amp alts alot cheaper,  if yours is like mine you may not have to fab too much,  the turnbuckle is adustable.

a lot is what i remember from the old board  maybe some other, brighter ones will chime in

HTH
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« Reply #11 on: August 23, 2007, 08:56:19 PM »

Be very careful if you remove the DN50, especially by yourself.  It is very heavy.  I removed mine by myself, but I'm only 35 years old.  I'm planning to have help to put it back in as getting it back in will be more difficult.

I wouldn't want to see someone getting hurt working on a bus.
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« Reply #12 on: August 23, 2007, 09:36:20 PM »

Be very careful if you remove the DN50, especially by yourself.  It is very heavy.  I removed mine by myself, but I'm only 35 years old.  I'm planning to have help to put it back in as getting it back in will be more difficult.

I wouldn't want to see someone getting hurt working on a bus.

He's right about that, I took mine out and replaced it by myself.  wouldn't reccomend to anyone

the nine has a hatch in the floor right above it too.
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« Reply #13 on: August 23, 2007, 10:05:11 PM »

NCBob - you are just close enough to contact Gene Rochester in Walhalla SC - HE knows more about alternators than ANY human being on earth - unfortunately he's not a busnut anymore - old phone numbers are (don't know if they're any good now) 864 882 3636 & 864 888 8578 - HTH
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« Reply #14 on: August 24, 2007, 04:36:41 AM »

Many thanks to all of you for your advice and information. This situation isn't really over my head, so to speak, but it reminds me of when I was a kid....having measles was a terrible inconvenience but knowing that the neighbors' kids had been there or were there sure made the suffering less intense. Huh

I will attack the problems with renewed vigor this morning....thanks again to all.

Bob
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« Reply #15 on: August 24, 2007, 09:01:46 AM »

Bob, I may have a voltage reg here. If intrested I will take a look, it worked when I removed it.  Tom Y
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« Reply #16 on: August 24, 2007, 02:51:08 PM »

Y not Tom?  Pun intended with no offense meant. Cheesy  Since we're already trying to do some business...what would be the effect of monkeying around a bit more?

It might mean a separate shipment ...I don't think the regulator and the muffler would get along on the trip here (sort of reminds me of my ex-wife and me)..but let me know the price and the shipping and we'll git 'er done!

And thanks for the reply.....

Bob

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« Reply #17 on: August 24, 2007, 03:00:10 PM »

And I almost forgot...Thanks to Niles I spoke with Gene Rochester in Walhalla, SC today....what a neat guy!

He's a former BusNut who's built more than his share of Eagle's and knows most of you old timers.  He particularly asked me to remember himself to Jack Conrad.  I'm sure that if Jack had known he was this close to us here in Franklin he'd have opted for a quick ride down there to renew an old friendship.

Gene is building 5/8 or 3/4 scale model Mack trucks for a hobby now on Ford and Dodge chassis.  Tom and I are going to take a day and go down and meet him and see how much fun a Busnut can have after he finds something more interesting than buses.

More at another time....

Bob
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« Reply #18 on: August 24, 2007, 04:46:17 PM »

"I removed mine by myself, but I'm only 35 years old.  I'm planning to have help to put it back in as getting it back in will be more difficult."
------------------------------------------------------------
So at 62 yo it was only natural that I felt a bit sore after removing it by myself, stripping it and replacing the stator, AND putting it back by myself last week.
Looks like I'm not going down hill quite as fast as I thought.
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« Reply #19 on: August 24, 2007, 08:55:02 PM »

"I removed mine by myself, but I'm only 35 years old.  I'm planning to have help to put it back in as getting it back in will be more difficult."
------------------------------------------------------------
So at 62 yo it was only natural that I felt a bit sore after removing it by myself, stripping it and replacing the stator, AND putting it back by myself last week.
Looks like I'm not going down hill quite as fast as I thought.

Well, I wasn't sore after removing the alternator.  It is just difficult because I was lifting a heavy weight from a fairly high and akward position.

I could perhaps get it back on the mount myself, but getting the bolts to line up would be difficult.
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« Reply #20 on: September 08, 2007, 06:41:15 PM »

I'm resurrecting this thread only for the reason that the topic is one we might all encounter at some time or another. And, the fact that my bus is 39 years old and they've made some serious changes in alternators in the interim.

My 50DN (old style) is an AC, 3 Ph, generator (using the term used back then) it has stationary fields and a rotating armature...contrasted to the rotating field (rotor) and stationary field (stator) of the later units. It is NOT oil lubricated and/or cooled (which in itself is a revelation) and has the typical 3 ph bridge rectifier to put it into that, by today's standards, the alternator classification.  It still uses the black (read Big Ugly Black Box) voltage regulator associated with the later style 50DN alternators.  MCI refers to it in 'Da Book' As a generator.

Without the new regulator in the circuit I 'full fielded' the generator with 24VDC (after cutting back the wires and soldering new terminals on them) and got a spark.  "Da Book' says that the field coils have a normal resistance of 3.9- 4.2 Ohms.  OK, that value would cause enough spark that I got....but not the output that I expected....28VDC.

Since this is a rotating armature that tells me it has brushes to collect the AC to send to the 3PH diode trio. Lightbulb!  I might have something simple like worn or broken brushes!

Unfortunately that means I'll have to pull that ratch-a-pratch rascal out of there and put it on the bench for further testing.  Stay tuned for the ongoing saga of NCbob and his project of the moment.

And don't forget to save your cereal boxtops to send in for your magic de-coder ring to find out what the secret message is for next weeks' adventure!

With tongue-in-cheek.....

NCbob
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« Reply #21 on: September 08, 2007, 07:13:37 PM »

NCbob: Don't get too involved with nomenclature in the book. Remember that the maintenance manual was written for bus mechanics who had been working on generators on all the previous models and may have never seen an alternator. They provided step by step instructions on how to test it. Your experience with gen sets may be making it appear more complicated than it really is.
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« Reply #22 on: September 08, 2007, 07:17:21 PM »

Unless it is completely different to my 50DN, it has a fixed field and a fixed stator winding with a rotor rotating between  and is brushless.

If you were running the alternator without a load (not a good idea anyway) and without a regulator I would have expected a higher output voltage, but maybe not.

If you dismantle it, just unbolt the drive endshield and withdraw the stator. To get the other end off requires the diode assembly to be dismantled first.
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« Reply #23 on: September 08, 2007, 09:55:40 PM »

Bob, it sounds to me like the alternator behaved exactly as it should for the way you tested it; and it doesn't use brushes, so you don't have to worry about that.

Our manual gives a good, detailed instruction on servicing the alternator. It was very enlightening reading for me!

For what it's worth.

Tom Caffrey

I'm resurrecting this thread only for the reason that the topic is one we might all encounter at some time or another. And, the fact that my bus is 39 years old and they've made some serious changes in alternators in the interim.

My 50DN (old style) is an AC, 3 Ph, generator (using the term used back then) it has stationary fields and a rotating armature...contrasted to the rotating field (rotor) and stationary field (stator) of the later units. It is NOT oil lubricated and/or cooled (which in itself is a revelation) and has the typical 3 ph bridge rectifier to put it into that, by today's standards, the alternator classification.  It still uses the black (read Big Ugly Black Box) voltage regulator associated with the later style 50DN alternators.  MCI refers to it in 'Da Book' As a generator.

Without the new regulator in the circuit I 'full fielded' the generator with 24VDC (after cutting back the wires and soldering new terminals on them) and got a spark.  "Da Book' says that the field coils have a normal resistance of 3.9- 4.2 Ohms.  OK, that value would cause enough spark that I got....but not the output that I expected....28VDC.

Since this is a rotating armature that tells me it has brushes to collect the AC to send to the 3PH diode trio. Lightbulb!  I might have something simple like worn or broken brushes!

Unfortunately that means I'll have to pull that ratch-a-pratch rascal out of there and put it on the bench for further testing.  Stay tuned for the ongoing saga of NCbob and his project of the moment.

And don't forget to save your cereal boxtops to send in for your magic de-coder ring to find out what the secret message is for next weeks' adventure!

With tongue-in-cheek.....

NCbob
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« Reply #24 on: September 09, 2007, 04:21:37 AM »

Well, boys and girls, this old fart has no choice but to offer an opinion. With the understanding that opinions are like a part of the bodily anatomy that everyone has.

The first and main clue is that Bob indicates that it has a three phase diode bridge rectifier. That simple fact identifies it as an alternator as opposed to a generator and it is a revolving field design for the following reasons.

Therefore, it has two light duty type brushes connecting the DC field control voltage from the voltage regulator, thru a set of slip rings, to the revolving field. The main AC power output (at high frequency) is taken from the stationary windings and routed thru the bridge rectifier to convert the AC power to DC.

I do not believe it has three sets of brushes for the main AC power for two reasons. That design (generator) used commutator bars, instead of slip rings, to collect the output power and the commutator bars actually had the purpose of converting the generated power directly to DC. Therefore the three phase full wave bridge would not be required.

It absolutely will not harm an alternator to operate it with no load forever. The output voltage is controlled by the field voltage which comes from the voltage regulator. The voltage regulator senses the battery voltage and controls the output voltage accordingly. At full forcing voltage from the field the output voltage should be in the 30+ voltage range for a 24 volt rated alternator. With no load on the alternator, there is no current flowing in the output circuit, so therefore the alternator can not be harmed.

It was mentioned that there are no brushes in an alternator, and this is correct for an industrial stationary alternator. These brushless devices have an additional rotating component. These devices have a rotating exciter with a DC control voltage connected to the stationary windings. This causes an AC voltage to be generated in the rotating component. This AC is then rectified by a revolving three phase diode bridge whose output is connected, along the rotating shaft, to the rotating field windings of the main alternator. This voltage then controls the output of the alternator (AC) stationery windings which is then rectified by the bridge rectifier to provide the main DC output.

The main difference between a generator and an alternator is that a generator produces a DC voltage directly, via the action of the commutator bars whereas the alternator produces an AC voltage which is converted to DC by the three phase diode bridge.

This is only an opinionated opinion and should be taken for what it is worth. I am more than willing to listen to other opinions but I can assure you that it will be very difficult for you to change mine. LOL

Richard

PS: As an afterthought, and if anyone is interested, all rotating devices produce an AC output initially. The primary difference is that a generator produces this AC on the rotating armature and converts this AC to DC by use of the commutator bars on the rotating armature and the brushes on the fixed portion of the device.

The alternator produces this AC voltage on the fixed (non rotating) armature  and converts it to DC by use of the three phase bridge diode assembly.


« Last Edit: September 09, 2007, 05:14:14 AM by DrivingMissLazy » Logged

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« Reply #25 on: September 09, 2007, 07:54:26 AM »

Delco Remy's website says the 50DN has no brushes.  This is not to say the design may not have changed over the years.
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« Reply #26 on: September 09, 2007, 08:54:51 AM »

The oil cooled 50 DN alternator does not have brushes.
It does have a fixed field coil, fixed stator, a spinning rotor and a diode bridge rectifier.
It does weigh approx 85lbs.
When testing any charging system you must make sure the batterys good first - charged,load tested,specific gravity,cables and connections,etc.

The "full field" test should not be performed for more than 3 seconds in my opinion.
It can create an output of up to 32 volts with almost 300 amps.
You MUST be extra careful if you have to perform this test.



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« Reply #27 on: September 09, 2007, 09:19:00 AM »

The oil cooled 50 DN alternator does not have brushes.
It does have a fixed field coil, fixed stator, a spinning rotor and a diode bridge rectifier.
It does weigh approx 85lbs.
When testing any charging system you must make sure the batterys good first - charged,load tested,specific gravity,cables and connections,etc.

The "full field" test should not be performed for more than 3 seconds in my opinion.
It can create an output of up to 32 volts with almost 300 amps.
You MUST be extra careful if you have to perform this test.




Thanks, Sammy. It must have a separate rotating exciter also, as I mentioned in my writeup.

Also the output of the alternator should generally be disconnected before a full field test is conducted, although as you indicate, 300 amps for a few seconds would not do any damage. Does anyone have an electrical diagram of this device?
Richard
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« Reply #28 on: September 09, 2007, 10:16:06 AM »

Richard, I'll check my library to see if I might have something on the 50 DN for you.
I don't know about a separate rotating exciter - I have never seen one on the oil cooled units i have rebuilt.
They normally don't charge unless the field coil is energized.
The field coil will have different terminal lead configurations, depending on the application.
One example: one lead of field coil is your F1 terminal, other is the F2 terminal.
Second example: one lead of field coil is your F1 terminal, no external,visible F2 - usually grounded to unit inside.
Some have jumper straps from F2 to ground (unit housing).
Some have buss bar from BAT post to F1.
The control circuit to the field coil can be many different configurations also.
Some control a positive voltage to the alternator field coil, some voltage regulators control the ground side of the coil.
Just showing different types of configurations you might come across, no disrespect intended.
Regards,
Sammy  Cool
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« Reply #29 on: September 09, 2007, 10:33:49 AM »

No, Richard, there's no outboard exciter on this alternator.  Too, something I not only didn't mention nor did I test, is that there is another relay in the circuit, a load relay I believe, but that shouldn't come into the picture...yet.  The alternator relay closes with the closing of the master switch so I then have power to the + terminal for the regulator.

I guess it boils down to whether or not there are brushes in this old alternator and I suspect there are not as the cross section of the MC5A Repair Manual shows none.

I will read the field resistance today (guests coming for supper) and that should throw more light on the mystery.

Bob
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« Reply #30 on: September 09, 2007, 11:22:20 AM »

No, Richard, there's no outboard exciter on this alternator.  Too, something I not only didn't mention nor did I test, is that there is another relay in the circuit, a load relay I believe, but that shouldn't come into the picture...yet.  The alternator relay closes with the closing of the master switch so I then have power to the + terminal for the regulator.

I guess it boils down to whether or not there are brushes in this old alternator and I suspect there are not as the cross section of the MC5A Repair Manual shows none.

I will read the field resistance today (guests coming for supper) and that should throw more light on the mystery.

Bob

Boy, I would really like to see one of those animals. In the 50 years and thousands of different type alternators and generators going back to 40's era design, I have never heard about anything like this.
Richard
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« Reply #31 on: September 09, 2007, 12:09:54 PM »

Richard,

I went to a vocational high school to become an "industrial electrician".  That was in 59 and in the era that this technology would have been current.  I studied all sorts of generators, both AC and DC, and I never heard of it either.  Slip rings for AC and commutator for DC....PERIOD.  In the ensuing 30 years in the field of electronics (broadly) it never surfaced.  It would be nice to be able to UNBOLT the stator and field windings and those diodes must be real pieces of serious work to stand up to engine room temps for 30 years.  A remote three stage regulator would be somthing to wish for.  Lasted 39 years.  If I didn't have one of these puppies, I would be looking for one.    It might need bearings and diodes and that shouldn't break anybodys bank.  If you handed the field to ANY motor rewinding shop it would not cost that much to have it done.  If you will go for $800 for a new stator or $1,900 for a rebuild....I now of a local generator/starter rebuilder that will let me co-locate and I will go into bus.  274 amps!  Who knew?Huh

I'm half serious here and I will give a warranty.  Mostly I am making a point.  You have company, Richard.

John
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« Reply #32 on: September 09, 2007, 01:37:12 PM »

Fortunately, for me, there's an expert nearby. Thanks to a previous poster I learned about Gene Rochester who is nearby in Walhalla, SC.  Some of you may remember Gene...he's a former BusNut and Eagle expert who owns a very large alternator/starter rebuild shop either in Greenville or Spartenburg, SC. Gene still maintain a small shop in Walhalla for his hobbies...building scale model Mack trucks.

I spoke with him again the other day and it didn't take long for me to realize that this guy is sharp.  He told me that he's more concerned with 'ripple voltage' getting out of the alternator than any other factor...that it eats batteries like Pacman on a binge!  Over my head, for sure....but I fell I'm in safe hands.

Rebuild costs? This is a bus...and it's our home and our link to travel to be with our family and BusNut friends. In for a dime....in for a dollar. What am I going to do?  Plant flowers in it for lack of an operating component?  Not so's you'd notice.

All I lack at this point is a willing pair of strong arms to pull that rascal out (and I know a fellow who matches that description) and I'll take it to Gene, after I do some preliminary checks, and we'll get the job done.

I'll keep you posted, if you'll allow that, so that the archives will reflect the experiences and advice offered here. Isn't that what this Board is all about?

Thanks again for your input and thoughts....and the beat rolls on.......

Bob
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« Reply #33 on: September 09, 2007, 01:56:20 PM »

Bob,
   Please do me a favor and tell Gene I said HI.  I knew he had a shop in Spartansburg, but did not realize he lived in Walhalla. I sure would have stopped by to visit if I had known.  Ask him if he still has his "Bumper Dumper"? That might be a nice addition to your bus.  Did you know he still holds the speed record for class 8 Semi Trucks at Atlanta Motor Speedway. He set the record back when they had the Great American Truck Races.  Jack
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« Reply #34 on: September 09, 2007, 02:40:58 PM »

Bob,

Glad you got hooked up with a tried and true expert.  And a bus nut to boot!  You are homefree as far as I am concerned.

Your comment about "ripple" is pregnant with meaning for me as that anomaly has surfaced many times in my career.  Knowing nothing about that design of generator, it would make sense that it has fallen out of the mainstream if it has ripple as a characteristic.  Then again, all alternators have ripple as they are unfiltered.  When an alternator looses a diode it developes very high ripple.  I really hope you will be able to expound on the "eats batteries like pacman" comment.  Really, I do.

Thanks,

John
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« Reply #35 on: September 09, 2007, 11:57:25 PM »

Richard, the 50DN really doesn't have any brushes. Not a single one.  There are no slip rings or commutator either although I guess the design of the stator acts as a sort of magnetic commutator.
If you want an exploded view let me know and I will email it to you - although my copy is not too sharp and it may be difficult to get an idea of how it is constructed..
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