D2 Generator to alt conversion

[Old Magnet]

Found yet another picture of a direct drive unit.....good view of coupling and cooling fan feature.

[alan627b]

Has anyone ever seen a later (1V series) DW10, with the D318, with a direct electric starter? My bellhousing is already drilled and has a bolt on cover plate on it, but there doesn't appear to be enough room between it and the shaft coming out of the steering box to allow one to fit. It would have to have a very short starter body to make it work.
Just curious...
Alan627b

[2bluejon]

Well tonight i put part of the alt together and i did a RPM CK and the Low Rpm was 1100 and the High Rpm was about 3100 so i think that that is enuf rpm that was coming off the back of the old gen shaft in the cat thanks

[8C 361]

On the Farmall board some of the guys speak highly of the Japanese alternators they use on Nissan trucks. Maybe that would be something to consider.

Tom

[sandcreek]

Please post a price of your kit when it is finished. I would be interested in one if price is reasonable.

[OzDozer]

OM - How many different generators are there on the older Cats? I have one off the RD-4 that we are currently designing an adaptor for .. but I wondered how many different adaptors are needed to cover all the engines from the mid 1930's to the late 1950's.

My buddy and I have been doing some brainstorming, and have come up with a simple, compact adaptor that utilises a 10SI alternator, fitted directly to the generator drive gear.
We believe this setup is simple and effective .. and will be a lot cheaper than the designs you pictured previously, that entailed using a lovejoy coupler.
There is a small amount of extra work involved in coupling/decoupling the alternator, over and above the lovejoy coupler design .. but not enough to make coupling/decoupling a chore.

Our design involves the requirement of some machining on the inner bore of the generator gear .. as well as a specially-machined, sleeve-style, retaining nut .. to enable the coupling of the gear directly to the alternator shaft. The alternator pulley is removed, but the fan is left in position. There is one additional bearing and a spacer in the design, besides the mounting/adaptor plate.
We should have the working model finished and installed on the D4400 by next weekend.
Pics will follow, and if general approval by consensus, of the design, is reached, we will have the adaptor available for general sale.

[Old Magnet]

Hi Oz,
I haven't really payed that much attention. There certainly are many styles but I don't think there are more than two-possibly three different diameters. I am guessing but will root around in my assortment and measure what I have.

I could live without a flex coupling if you can control alignment but I feel the cooling fan is a must, along with ventilation flow. Be sure to include the adjustment slots in the ASME flange mounting if you are starting new.
Will this be a two bearing or three bearing shaft arrangement when assembled?

[OzDozer]

The new flange mounting will be a nearly exact copy of the original Cat generator flange .. and there will be one extra bearing, mounted in the centre of the new flange mounting plate.

The fan stays in place .. the pulley is removed .. and spacers and bearing are fitted onto the end of the alternator (rotor) shaft. The flange mounting is slipped over the bearing with a normal bearing installation clearance fit. The spacers and bearing are retained by a sleeve-style, or barrel-style, specially machined nut .. which effectively carries the bearing and gear.
This sleeve-style nut, when tightened on the rotor shaft thread, clamps the gear, spacers, additional bearing, and rotor shaft, tightly together .. exactly as happens when the nut on the pulley is tightened under normal alternator assembly.

There are angle-iron brackets welded to the flange mounting plate, which mate with the original alternator bottom mounting lug, and the adjuster lug .. and two bolts in these lugs retain the alternator in position, and align it. The additional bearing also assists with alignment.

For alternator replacement, the entire assembly is unbolted at the mounting flange, and the sleeve-style nut undone, to disassemble.
A new or replacement alternator then has the pulley removed, and the spacers, bearing, flange mounting plate, gear and sleeve-style nut, are reassembled and tightened. The whole assembly is then bolted back up to the timing cover.

Why are the slots needed in the flange mounting? .. is there a range of different mounting holes between the various Cat engines? Many thanks for your great assistance.

[Old Magnet]

Hi Oz,
Generally a three bearing support requires the flexibility of a coupling to maintain alignment and equal bearing loading.

In reading your description a seems you have three bearings on the shaft, the two alternator bearings plus the drive end bearing supported on your sleeve. This would appear to give you two bearing support (desired for no coupling) but the clamping of the alternator housing returns it to a three bearing support with the coupling requirement again.

The slots are your gear mesh/backlash adjustment. It is not a full diameter piloted mount so there is room to float (rotate around the bottom bolt axis) the mounting. Not sure you could guarantee mounting if you have a fixed flange drilling. All the factory generators I've seen have the slotted flange.

If I am envisioning this correctly the angle iron brackets are standoffs (horizontal) for the alternator mounting and provides the ventilation access, is that correct? Should work fine and avoid a lot of lathe work.

Will get the dimensions I mentioned today.

OK,
Out of six generators I find housing diameters of:
4 3/8
4 1/2
4 7/8
5 1/2 (24V unit)

All are adapted with various bolt pattern end plates to fit the one SAE dimension flange.

[OzDozer]

OM - O.K., thanks for the info in relation to the reasons for the flange mounting slotting. The gear mesh adjustment reason never occurred to me.

I understand where you're coming from, on the 3 bearing support requiring a coupling to eliminate rotor shaft stress. I don't believe this will be a problem on our adaptor, because of the following reasons ..

1. The assembled components comprise a very stiff assembly, able to withstand any small amount of misalignment.

2. Bolting up the alternator housing will not create any serious misalignment, as the angle-iron brackets will be welded into positions that will essentially keep the alternator in line.

3. Any slight misalignment will be compensated for, by the third bearing being able to twist slightly in the mounting flange, with normal bearing fit clearance of, say, .0005" to .001".

4. The rotational speeds are not substantial enough to create high shaft stress. The alternator rotor shaft is a pretty robust shaft (17mm diameter), and I seem to recall the alternators are regularly capable of, and attain, speeds of up to 12,000-14,000 RPM under high-speed automotive use. We're talking about 1/8 of these speeds in antique Cat tractor applications.

Yes, the angle iron brackets will be a stand-off style. The fan will be running fairly close to the mounting flange plate, as this assists in air flow, anyway.

My other concern would be related to trash and dust getting sucked through the alternator on a constant basis, as is common with nearly all crawler applications. Has this ever posed a problem to tractor owners who currently have Delco 10SI's fitted?

I would imagine a light trash screen, mounted on the rear of the alternator, would be a highly advisable addition.
The standard Cat alternators and generators, have, or have had, generous-size bearings, that coped with heavy concentrations of dust and trash .. as well as inbuilt trash screens.
I'm not sure that the automotive bearings in the 10SI have the same ability to cope with heavy dust and trash concentrations. I'd like to hear opinions.