CD 840 (from 733) Generator refurbishing/restoring

[34PackardRoadsta]

Dear folks,

Well, I got the correct generator for my car from a fellow in Minnesota. I have taken it apart, and now I have some questions.

I guess the first question is can I refurbish this mostly on my own, or should I just put it together and send it off to get rebuilt? I have been told that I can find a local rebuilder and get it rebuilt for around $75. What does it mean to get a generator rebuilt? What would I get for my $75?

Now, some general observations and questions:

1) What is the best technique for general cleaning of armature, field coils, and commutator? I don't think I want to use brake cleaner, as it will strip insulation.

2) Insulation on wires coming from the field coils is shot, and the insulation on the field coils is coming apart. Furthermore, wires coming from the field coils are pretty frayed. Can I repair this, and if so how?

3) The shaft seal, which appears to be leather, is shot. First, is it leather? Second, where can I get one?

4) How do I tell if my brushes are too worn?

5) Do I reface the brushes if they are not too worn?

6) The commutator appears quite worn (see photos). What is too worn, and how do I fix it?

I have attached a few photos. As per usual, any and all info is greatly appreciated (in case I forget to thank you all later).

Cheers,

Tom

[34PackardRoadsta]

Adding photo of brushes

[Owen_Dyneto]

Looks like its begging for some TLC, though the brushes look OK. You won't get much for &75, probably cut the armature, undercut the mica, fix the field leads, and a quick slop of black paint. Whomever does it most likely won't even be able to bench test it because it requires a special test rig due to the lack of a front support and bearing. If you want a good, reliable generator I'd send it someone who specializes in OD generators. There was one such place posted on this forum fairly recently and if you can't find that, Googling "Owen Dyneto" should find it.

[Guest imported_Speedster]

I learned how to do it from reading repair Manuals, such as 'Motors Manual'. They have instructions for both repair and testing.

With simple hand tools and an Ohm-meter you can disassemble, clean and test, enough to tell if all the components are usable or not.

A test unit called a 'Growler' is the best way to test the armature windings, if you can find one, but the armature being shorted is Not a common problem, as long as the groves in commutator are cleaned properly.

If you find some problems, such as shorted windings, bad bushings, broken parts, etc., then those will need to be replaced or repaired, and you may need help with those. But if everything meets specs, per the manuals, then it's a fairly easy process.

The brushes do look okay, as well as the commutator (can't see any gouges or groves cut into it). Probably just needs a lite sanding with fine sandpaper. Even the seal looks good in the picture. (I made a new one from leather I got at Tandy-Leather shop.)

The wires that are going thur case should be Replaced or at least covered with shrink-tubing.

[34PackardRoadsta]

Rick and Owen,

Thanks for the info. Rick, what is a good supplier for shrink tubing (I am assuming you are talking about heat shrink)?

Also, in looking more closely at the parts manual, the seal is called a 'felt seal'. Rick, you said you used leather. Any reason that I should try to find the right 'felt' seal?

I have a Dykes and a Chilton manual, and perusing those is some help. It would be great to find a specific Owen Dyneto manual. Oh well.

Thanks again for the help.

Cheers,

Tom

[34PackardRoadsta]

Anybody have any luck with

Ace Alternator and Starter Exchange

or

Special Interest Autos?

Both claim to restore Owen Dyneto gens.

Probably best to PM with comments.

Thanks,

Tom

[Guest imported_Speedster]

Yes, heat-shrink tubing can be purchased many places online or at electronics supply stores. If you are going to use shrink-tubing then it's best to remove the wire form the holes in case, then shrink on the tubing before putting back it, instead of trying to put on tubing while wire is still in case.

My '29 generator had a leather seal, with a felt oil retainer/holder. The felt piece holds oil, to keep the bearing area lubricated and the seal keeps the oil in and dirt out.

If the felt piece needs replacing you may have to stack thinner pieces to get the correct thickness, if you can't find thicker material. I found felt at a sewing supply store, but that can probably be found easier Online, also.

[34PackardRoadsta]

OK. Mine doesn't have the leather washer. It is just the felt seal inside the little seal housing. Restoration Supply has 1/4" felt, so that should work. Now, how do you make the washer? It seems like you would want it to be a fairly tight seal, so an accurate cut would be needed.

Thanks,

Tom

[Guest imported_Speedster]

I don't know if the leather seal was original or not but it sure seemed like the best way to do it. Since it seals better. So I redid it the way it was. Altho it looked original, It may have been overhauled before, cause everything was in very good condition, except for the external wires.

I used round hole punch (that you hit with a hammer) to start the inner holes, then cut with sissors to proper size, in both the felt and leather pieces, and also cut the outer diameter with sissors, using the retainer as a size guide.

The hole punches can be puchased at tool supply store. I got mine Online, from Harbor-freight, but proper holes can be cut without the punch, it's just easier to start the holes that way.

See Link:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=3838

Restoration-Supply probably charges about 10 times more for their felt than the Sewing-supply did. I know they do for everything else they sell.

I also cut donuts, from that sheet of felt, to oil and put over 9 cars battery-posts, to keep them from corroding, (which is what I originally got the sheet of felt for). So I had experience cutting donuts, after doing 18 of them. LOL

[34PackardRoadsta]

Well, Rick, I have a feeling you are far better with scissors than I . With my big mitts I can barely find a pair of scissors I can use!

The felt RS sells is good from -80 to + 200 F, and sells for .35 per square inch. This seems pricey, but all I need is about 4 square inches (assuming I screw up 3 times before getting it right). So $1.40.

Maybe I can find one of those 'craft' hole cutters that will adjust down to the size I need.

Now, is there a trick to removing the screws that hold the field coils in place? They really seem stuck, and this doesn't strike me as an application where they should get that stuck.

Cheers,

Tom

[Owen_Dyneto]

Yes, the screws that hold the field in should be VERY tight, so tight in fact that a special rig is used to remove them. It's pictured in most any general auto service book of the era, kind of an arbor press to hold the bit firmly into the screw head and then a long lateral handle. It will be very tough indeed to get them out without it.

PS - I could be incorrect by the item you're calling a seal I believe is in fact an oiling wick and if so should be felt, leather would be OK if its just a seal but I don't think that's the case. Jute carpet underpadding would probably work well if you can't find an old felt hat to cut up.

I took a closer look at the commutator on your armature, it's obviously been cut several times and hopefully has one more left in it because I don't think just cleaning with crocus or emery will give a very satisfactory life.

[34PackardRoadsta]

Thanks for the info on the field coils. I have seen pictures of a press being used on a gen, but did not understand. Thanks for clarifying. I will try to find somebody around here that can do that sort of work. Hopefully my machine shop can.

I am going to bring the armature to the machine shop for commutator cutting. If it is too far gone, I guess I need to try to find another armature. I just cleaned up the brush holder and brushes. The brushes seem fine after a bit of sanding. The holder was pretty gunked up, but I eventually got it clean.

There is a fair amount of oily junk in the armature windings. Should I try to clean that out?

Thanks,

Tom

[Guest imported_Speedster]

I wouldn't remove the field windings, unless you've determined they are damaged or shorted, and if they are then you will probably want to get another generator anyway, since good windings are more difficult to find than complete generators.

A complete cleaning is very important. Just be sure not to damage the wires when cleaning them. Acetone is a good cleaning liquid to use and use an air-compressor to get everything out. Cleaning the commutator groves is very important.

I don't like to have the commutator cut down unless absolutely necessary, (due to groves around it or gouges in it), since every time you do it that shortens it's life. If there's a fairly smooth surface, which it appears to have, only sand or clean it as necessary.

[34PackardRoadsta]

Rick,

The commutator surface is quite grooved. It definitely needs to be cut down. One thing I don't understand is how it got so grooved in the first place. The grooves are roughly evenly distributed across the facings, and around 1/100"-1/200 of an inch deep. As Owen mentioned, the commutator has already been cut at least once.

Obviously, the brushes were equally beat up, but I got them pretty well smoothed out with some sanding.

What is the best way to attach new leads to the field coils. I was going to silver solder them. Also, what gauge wire should I use for the main and third brush wire leads?

Thanks,

Tom

[Guest imported_Speedster]

The brushes are grainy, non consistant hardness, so as small softer areas of the brushes get chipped away, the remaining harder areas act as abrasive grit, cutting into the soft metel of commutator, then the higher areas of the metal chip out more of the brushes, which very quickly cause deep groves.

I think the wire size is 10 or 12-gauge, but I'd have to compare to find out for sure.

[34PackardRoadsta]

Rick,

Thanks for the info. I have a little bit of wire from the leads that I can use to gauge wire size. I thought they were too beat up to judge size, but there is still enough near the field coils to get a size.

Again, is silver soldering an ok way to attach new leads? Also, I was going to wrap the modern wire in black cloth friction tape to make them look 'correct'. Is there any problem in doing this?

I appreciate your help with my persistent questions . I am even more of a new guy at this gen stuff than I am with the other mechanical stuff.

Cheers,

Tom

[Guest imported_Speedster]

Yes, silver-solder would be great. Ordinary tin-solder will work fine tho. Just be sure to hook and twist the wire ends (or crimp lug-ends) before soldering, for a good mechanical connection as well.

Be sure to compare the internal conductors of the wire, not the thickness size of the insulation, which may be different for different types of insulation.

Original cloth-covered type wire, in any quantity you need, is avaiable from wiring harness makers such as Rhode-Island-Wiring, if you want to go that route. I've never tried cloth-tape, for that type repair, so don't know how well it would last (I've had trouble with it staying in place). I've always got original type wire (found some on eBay) or just used shrink-tubing over original wire, if I wasn't worried too much about original look.

See Link:

http://riwire.com/

I guess I need a Bigger computer Monitor, cause on mine that thing looks Smoother than Pamela Anderson's rear. LOL

[34PackardRoadsta]

OK, I have made new leads, cleaned and tested armature and field coils, and all that good stuff. I am bringing the armature for cutting to a local shop tomorrow. So, I need to start putting things back together. My questions now are:

1) Based on my photos and looking at the wiring diagram (attached), I can't tell which wires go where! Aiiigh . So, I have two wires coming from the field coils, a thinner wire and a larger wire. Somehow, I also get two wires out the beast, one main gen wire, and a field wire. In looking at the photos and the diagram I think: their should be a wire coming from the ground post on the brush holder and exiting the gen; and one coming from the main brush on the top of the picture and exiting the gen. The ground brush is just grounded. Is this correct? and where do the field wires go?

2) From photos, it looks like the correct finish is a 'wrinkly black' on the field coil housing. If so, how do you get this kind of coating? I have seen paints like this:

http://vht.carshopinc.com/product_info.php/products_id/56287/SP201

is that the right way to go.

Thanks tons for the help. This has been quite the interesting project.

Tom

[34PackardRoadsta]

OK, I have made new leads, cleaned and tested armature and field coils, and all that good stuff. I am bringing the armature for cutting to a local shop tomorrow. So, I need to start putting things back together. My questions now are:

1) Based on my photos and looking at the wiring diagram (attached), I can't tell which wires go where! Aiiigh . So, I have two wires coming from the field coils, a thinner wire and a larger wire. Somehow, I also get two wires out the beast, one main gen wire, and a field wire. In looking at the photos and the diagram I think: their should be a wire coming from the ground post on the brush holder and exiting the gen; and one coming from the main brush on the top of the picture and exiting the gen. The ground brush is just grounded. Is this correct? and where do the field wires go?

2) From photos, it looks like the correct finish is a 'wrinkly black' on the field coil housing. If so, how do you get this kind of coating? I have seen paints like this:

http://vht.carshopinc.com/product_info.php/products_id/56287/SP201

is that the right way to go.

Thanks tons for the help. This has been quite the interesting project.

Tom

[Guest imported_Speedster]

The drawing is for the latter 3-terminal type regulator and gen, not the simple Cutout with only 2 terminals (in and out).

The 2 gens are wired differently internally.

Are you saying the generator wires do not match the drawing?

You did make your own drawing of the generator, as to where the wires went, before you took it apart, didn't you ?

Isn't that gen, that you are overhauling, the early type that requires a cutout, not a regulator???

I don't remember what gen and reg you ended up with and are trying to use ??? Is the gen the 800, the 840 or the 865?

[Guest imported_Speedster]

The drawing is for the latter 3-terminal type regulator and gen, not the simple Cutout with only 2 terminals (in and out).

The 2 gens are wired differently internally.

Are you saying the generator wires do not match the drawing?

You did make your own drawing of the generator, as to where the wires went, before you took it apart, didn't you ?

Isn't that gen, that you are overhauling, the early type that requires a cutout, not a regulator???

I don't remember what gen and reg you ended up with and are trying to use ??? Is the gen the 800, the 840 or the 865?

[Owen_Dyneto]

You can get black krinkle paint from Eastwoods,among others. I confirm the wiring diagram above for an Owen Dyneto CD-865 for 726/733.

[Owen_Dyneto]

You can get black krinkle paint from Eastwoods,among others. I confirm the wiring diagram above for an Owen Dyneto CD-865 for 726/733.

[Guest imported_Speedster]

Owen, (and anyone else that knows)

I'm still confused about the difference in CD-840 and CD-865 ? (Both of which were used in '30)

Are those two wired the same internally and require the same regulator?

Or is the CD-840 more similar to the CD-800 (which was used in '29)?

[Guest imported_Speedster]

Owen, (and anyone else that knows)

I'm still confused about the difference in CD-840 and CD-865 ? (Both of which were used in '30)

Are those two wired the same internally and require the same regulator?

Or is the CD-840 more similar to the CD-800 (which was used in '29)?

[34PackardRoadsta]

Ok, right, lots of different options. The gen is the CD 840. Obviously, I forgot this when looking at the diagram.

Also, no, I did not make a drawing . I took pictures, and thought they would be like a thousand words or something. So, there are still supposed to be two wires out, and there are two leads from the field coils, and three brushes. One brush goes to ground (on the brush holder holder), one brush goes to the lead that leads out. That leaves me with two wires I should know about, but don't because I am an idiot .

Owen, thanks for the lead on the wrinkly paint. I guess this is the correct kind of coating, and these are the products folks use. It just seemed too easy...

As always, any help much appreciated. I will post a drawing once I get everything done correctly and confirmed to be working.

Tom

[34PackardRoadsta]

Ok, right, lots of different options. The gen is the CD 840. Obviously, I forgot this when looking at the diagram.

Also, no, I did not make a drawing . I took pictures, and thought they would be like a thousand words or something. So, there are still supposed to be two wires out, and there are two leads from the field coils, and three brushes. One brush goes to ground (on the brush holder holder), one brush goes to the lead that leads out. That leaves me with two wires I should know about, but don't because I am an idiot .

Owen, thanks for the lead on the wrinkly paint. I guess this is the correct kind of coating, and these are the products folks use. It just seemed too easy...

As always, any help much appreciated. I will post a drawing once I get everything done correctly and confirmed to be working.

Tom

[Guest imported_Speedster]

Sorry, I wasn't trying to make you feel Worse than you already do.

The 840 is the one I'm not sure about. The 865 should match the drawing you have, but I don't have any data on the 840 to let me know if it's more like the 800 or more like the 865 ???

Or 'Something Completely Different'. (as Monty Python would say)

[Guest imported_Speedster]

Sorry, I wasn't trying to make you feel Worse than you already do.

The 840 is the one I'm not sure about. The 865 should match the drawing you have, but I don't have any data on the 840 to let me know if it's more like the 800 or more like the 865 ???

Or 'Something Completely Different'. (as Monty Python would say)

[Owen_Dyneto]

Sorry I haven't followed the latest posts carefully, but if your generator only has a single lead coming from it, then it's meant to be used with a simple cutout relay. Why don't you just go to the PAC site, click on wiring diagrams, and look at the 6th series generator wiring (CD 800) and then the 7th series (CD-865), and the differences in the control circuits and generators. I've got fairly extensive info on the generators used by all makes in the 20s and 30s, and the CD-840 seems to be a phantom except in the Packard parts book.

[Owen_Dyneto]

Sorry I haven't followed the latest posts carefully, but if your generator only has a single lead coming from it, then it's meant to be used with a simple cutout relay. Why don't you just go to the PAC site, click on wiring diagrams, and look at the 6th series generator wiring (CD 800) and then the 7th series (CD-865), and the differences in the control circuits and generators. I've got fairly extensive info on the generators used by all makes in the 20s and 30s, and the CD-840 seems to be a phantom except in the Packard parts book.

[tbirdman]

Note on wrinkle paint. You can also probably get it at your local auto parts store. I found the best way to do the wrinkle paint is.

1. Put good coat of primer

2. heat object to be painted with heat gun or blow dryer

3. spray heavy coat paint

4. heat paint with heat gun or dryer

5. wait ten minutes and repeat steps 3 and 4 two more times

Few hours later you should have a nice wrinkled finish.

I also heard painting outside on a hot summer day makes everything a lot easier.

[tbirdman]

Note on wrinkle paint. You can also probably get it at your local auto parts store. I found the best way to do the wrinkle paint is.

1. Put good coat of primer

2. heat object to be painted with heat gun or blow dryer

3. spray heavy coat paint

4. heat paint with heat gun or dryer

5. wait ten minutes and repeat steps 3 and 4 two more times

Few hours later you should have a nice wrinkled finish.

I also heard painting outside on a hot summer day makes everything a lot easier.

[Guest imported_Speedster]

I'm starting to think the change from the 840 to the 865 was a mid-year change in '30, and the 840 is wired like the 800 (but has a higher current output than the 800), and requires a Cutout-relay like used on the 800.

Can anyone verify that???

[Guest imported_Speedster]

I'm starting to think the change from the 840 to the 865 was a mid-year change in '30, and the 840 is wired like the 800 (but has a higher current output than the 800), and requires a Cutout-relay like used on the 800.

Can anyone verify that???

[34PackardRoadsta]

Here is the wiring diagram from the 6th series generator (CD 800). The field wire goes to ground, not out to the fused regulator as on the 865. From the looks of the wiring diagram, compared to my photos, the CD 840 is much more like the 865 than the earlier generators. There are definitely two leads that leave the gen, and one of those leads I know comes from a brush.

Here is the 800 (probably) wiring diagram:

[34PackardRoadsta]

Here is the wiring diagram from the 6th series generator (CD 800). The field wire goes to ground, not out to the fused regulator as on the 865. From the looks of the wiring diagram, compared to my photos, the CD 840 is much more like the 865 than the earlier generators. There are definitely two leads that leave the gen, and one of those leads I know comes from a brush.

Here is the 800 (probably) wiring diagram:

[34PackardRoadsta]

Here is a shot of the 840 brush holder before I took everything apart. It is a closer shot than the one above.

[34PackardRoadsta]

Here is a shot of the 840 brush holder before I took everything apart. It is a closer shot than the one above.

[Guest imported_Speedster]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 34PackardRoadsta</div><div class="ubbcode-body"> There are definitely two leads that leave the gen, and one of those leads I know comes from a brush. </div></div>

But didn't the other of those 2 wires connect to case ground at the cutout-relay mounting screw?

That's the way my '29 800s are.

(That ground wire doesn't even need insulation on it, since it can only short to the case, which is ground.)

If so, I think the 840 is wired the same as the 800?

The main difference in the 2 versions is the way the ground side of the field-winding gets to ground. In the older version the field-winding is connected to an internal fuse and then to ground internally and in the newer version a wire is brought out to and thru the regulator and fuse to ground.

So, it's where the other end of field-winding, (not the end to brush,) is connected, that determines which type it is.

I think another way to tell is that If it has an Internal Fuse it requires a simple cutout, and if it doesn't it requires a regulator with built-in Fuse. Does the 840 have a built-in Fuse-holder?