I would like to thank the fellow member's who have responded with great information. I am amazed at how quick everyone jumped in to help. By luck, I mean just pure luck, I stumbled onto a flywheel housing of an parted out gen set D3400. Just waiting on a photo to confirm the housing has the 3 bolt cover. Dan

Also, you can pretty easily bore out the required hole with a SLOW speed drill and the correct hole saw. No lubrication required with the proper hole saw. I did mine in a bout 15 minutes with an air drill. Slow rpm.

Part Number 102751PT $39.95

I have found Old Caterpillar Magnets site and the drawing of the hole required for the starter. I have tried to print the drawing in several formats, however i can't get a clear drawing.
Hopefully someone can answer a few questions on the dimensions that I need in the drawings attached.
Why are the three 3/8 holes needed on the side of the housing?
Is dimension A 1 61/64 from center of bolt hole to edge of housing?
Dimension A to C is blurred.
Would anyone have dimension C to housing? Also dimension F to housing?
As for center is B 3.527inches?
There is a number on the lower part that I circled with a question mark, is it 4 5/16 ? it is point C to the other unmarked bolt hole.

The three 3/8 taped reference holes already exist in the tractor flywheel housing. Use the center of the top hole to locate the horizontal center of the big hole. Most use the 3-3/4 hole to get a little wiggle room. The 3-5/8 is a snug fit requiring very accurate boring. Use a carbide tipped tooth hole saw, no lube required as your boring in self lubricating cast iron.

i believe old magnet did had drawings on how to make the jig to drill those spots in the housing on d4 models i dont know if they would be the same. but yes its been done many times. personally i would convert the pony to electric start. as keeping it has advantages. but to each there own.

A big Thank You to Old Magnet for providing a clearer diagram. A friend of mine is an aircraft machinist and very particular for details, he will bore the holes on his mill. I also have to bring him the starter head as that he will ensure a perfect size and fit for the center hole.

As for the pony, I will be having the best of both for starting. The pony for the morning start and then the electric start for every time during the day of shut down and restart. I will be using the D2 at my cabin and every time I need to haul a load of gravel, its an hour round trip. After several loads, I will need the D2 running. I can't leave it running all day long, and electric would be convenient and a save on the pony for several starts a day.

TractorDanD2 wrote:

I would like to thank the fellow member's who have responded with great information. I am amazed at how quick everyone jumped in to help. By luck, I mean just pure luck, I stumbled onto a flywheel housing of an parted out gen set D3400. Just waiting on a photo to confirm the housing has the 3 bolt cover. Dan

I realize I'm late with this info but only an original inertia drive starter works with original flywheel housings without modification. Original direct start D2 starters have a drive gear that is about an 1/8" smaller diameter than what is used for conversions. So, either you have to offset grind the starter hole by about 1/16" and oversize the mounting holes or machine an offset to the nose of the drive end housing.

Old Magnet, thank you, its never to late to share information. While on the starter conversion topics, please have a look at the attached picture. Yesterday I came across another D2, 4U4176, 40inch gauge. At first I could not believe what I was looking at for an electric starter fit up.