Geoff Weeks

Well, I got the slip-rings and rear bearing off. P/S pulley puller got the outer slip ring, then I grabbed the rear bearing, but didn't realize there was a tiny snap ring between the bearing and inner slip ring (hidden behind a fiber washer and 75 years of crud) once that was off the inner slip ring and bearing came off together. Everything other then the bearings can be re-used.

Hardest part will be re-soldering the slip ring wires.

Messy bench time:

Puller arrived today, and although the paperwork that came with the kit shows a 3 jaw puller, I think the correct 2 jaw might work better. Came apart HARD, but likely hasn't been apart in 75 years. Good news is the kit will mate the rear bearing with no mod's.

Bad news is the rear bearing really should be replaced. It is dry and I could possibly clean and re-lube, on the other hand I have it this far apart. As stated earlier, the bearing is inboard of the slip-rings, so they would have to come off to get at the bearing. Not sure I could get them off in one piece.

Interesting construction, the rotor is made in three parts front and rear shell and shaft. Big nuts hold the shells on the shaft and allow field replacement of the field coil, and even voltage changes by changing the field coil itself. Something not seen on modern units.

Stator is bar wound and very stout.

I'll likely pick up new bearings in town, then see if I can remove the slip rings in one piece, even the manual says that isn't always possible. If it seams like there is a problem, then I'll order two new rings and make sure they are correct before I go further.

yeah, I found out once, never went back after that. It was why I said "old Boomtown".

Back in the 90's it had a big parking lot for trucks, then it got small then I think it went away altogether.

Since I never owned anything new than a '92 I didn't go west of Reno much.

30 years ago I was in my sleeper in the old "Boomtown" waiting for morning to pull an O/D load over the hill to Lodi. I heard a 6-71 jaking down the hill, and pull in next to me, an old rounded nose Freightliner, mid 60's. 

Somewhere on the .net there used to be a site where a Swiss trucker posted all his pic's from years of running from Europe all over the middle-east and even one trip to Pakistan via the Kiber pass (sp?). Almost all done in K100 KW with Detroit 2 stroke power.  1000's of pictures and stories to go with. I had it bookmarked on an old computer but somehow it got lost?

All in the days of real film, so much harder than today with digital photo's

I don't know if it is still all out there in cyber-land somewhere. 

From what I remember, my unit came off a late 40's GMC tow truck. It still had the original genny on it as well, and the owner didn't want both.

The alternators themselves date back to the 40's at least.

Looking at the kit, it could be easily reproduced. The original rear cover could be machined, the hardest part would be the new stamped steel cover that would have to be made fairly accurately so to clear the electrical parts while still ducting cooling air over the diode blocks.

I checked, the JB series will fit but are "backwards" in that the solid part of the block covers the cooling air duct,These have the diode toward the outside, and the JB has the diodes toward the inside.

Rather than get further off topic, I started a new thread here:

Cummins filter head on my 1942 IHC

Good reason to look up the parts book, and see what is required. I think the parts will be different for Mack rears vs. Eaton but am open to being corrected.

  On 2/23/2025 at 6:01 PM, Lmackattack said:

only thing to check at that point is if the axle tubes are the same size to accept any parts that clamp down on them to hold it to the suspension.  

 

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I have the complete manual for the suspension on my DT402, it shows the angle on the axle tubes for various axles, Rockwell and Eaton were something like 2-5 deg angle and Mack was 0, I think that would apply no matter what suspension you use because of the axle design and how the  power flows through.

From what I remember working on my Hendrickson clone, the axle seats are what sets the angle and the forward axle is different than the rear. I would think Mack top loaders would be the same as the Neway (0 deg angle) my DT 402s are on.

Kind of a long way around to say I think they would fit the axle tube but be wrong for the angle needed for Mack top loaders.

404 and 405 are different I'm not sure all the differences but I don't think they bolt into 402 housings. To new for a person like me!

As to what ratio, you have to run the math on what you have now, the transmission gearing and start ability on a hill with load, and make a selection that is the best for your needs.

You can build DT's to 3.70, I'd have to look but DS might go below that. DT's all take the same "carrier" while DS can use differing carriers for different ratios.

I'd rather put my money in getting the ratio right then the preferred maker of the axle. Unless there is a real problem with the design (Rockwell SQHD's were known for weak powerdividers) I just don't see what is to gain by switching makers. Most made in the last few decades are good, some do better in one area, but I can't think of a "bad" diff made in the last few decades.

I've run IHC (now sold as Spicer) Rockwell and Eaton, and can't say one is better or worse than the other.

When I changed from DS 402's to DT 402's the same driveline bolted right back up. When you switch makers you are going to have to make driveline changes as well adding to the cost for no gain.

If it is the Mack Clone of Hendrickson, I believe all the parts with the exception of the brackets that clamp around the axle housing, and may be torque arms the rest of the parts are the same. The clamping brackets set the shaft angle, on an Eaton it pitched "nose up" and Mack toploaders are level.

 I found out that Eaton housings are made that DS (single speed) housings will accept DT and DC  (two speed and Traction Control) center sections.

If your not changing the whole rear suspension, it seams like a lot of work and money to change axles housings for no gain. You can re ratio by just changing center drop out, and if you want more flexibility, add 2 spd centers for less work than whole cut off and change all the parts IMO.

Yes, the brushes are outboard of the rear bearing. While not as common as inboard, there are still some in use today that are like that. The Prestolite series comes to mind. They tend to be units that have ball bearings for the rear bearing. Ones with needle bearings that ride on the shaft have inboard slip rings. Brushed go in holders like this that screw into the rear housing .

In this case the internet is quoting the regs, both federal and state. So far you have not provided anything that shows they were cited for "caps on a steer", just hearsay that it happened.

You can look up the CFR and the NJ code for yourself. In both cases the exact regulation has been provided.

https://www.traction.com/en/p/a-c-heater-mack-unit-grey-mei10-9725

Some discharge vents are available for Air Source not sure the same ones that used. I thought you were looking for things like blower, Tx valve, drier and the like to get what you have there working.

As far as grill-densor's they don't work very well with R 134a, you would be better served with a modern parallel flow type when running R134a

R 134a needs a lot of surface area in the condenser, so many small tubes is better then larger widely spaced tubes.

as far as "cabinet" pieces, then no I don't know where to locate new.

Universal vent covers can be had by the size of the hole.

No idea what the "key hole" opening was for.

Red Dot still make replacement systems, or did when my Catalog came out.

#10-9725 for gray

#10-9726 for black

quick look shows

Evans

Kysor

Red Dot

and Signett

all made units for the R series. You'll likely need to know which you have for some of the parts.

What parts do you need? Most everything should be available from MEI-Airsource.

better picture of the bearing bore:

My thoughts also, but two of the bearings at least have the same ID so it should be as "simple" as removing the slip-rings and replacing the bearing.

I say simple, because I wouldn't attempt without slip-ring replacements being on hand. I think I have found those as well.