Hi waukman,
That's correct, putting 12 volt to the 6 volt pony starter doesn't hurt it a bit, even runs a little faster which can be a help. There are limits though, don't crank it to death:D I've run the same thing on my Ford 860 for years.
If it really bothers you, later pony electric starters did run on 12 v so the old 6 volt units could be readily converted by changing the armature and coils.
I charge my 24V system 12V at a time so no reason a switched 12V generator or alternator would not work.

"Old wrote:

You can add option # 3 if you have a mind to:)
It's possible to have both on the D4, just need to find space for battery/s or portable battery start. If you go the 12V route, the 6V pony electric start will operate fine.

Not a lot of option on the pony parts. Rings can be had readily aftermarket, pistons seem to be Cat only. Cylinder sleeves are aftermarket. Valves can be substituted. If you can make your own main bearings (T-something aluminum) you can save a few bucks and customize the thrust clearances. Seems machine shops don't know what to do with that block anymore. The crankshaft can be a cost killer, most are cracked, weld build up/repair is pricey. Be sure to check thickness and for cracks on the bottom of the cylinders where they all rot out or freeze burst before investing. Rod bearings are a Cat item. Camshafts and gears seem to go forever.

On the Direct Start, keep an eye on ebay. I've seen some pretty good deals there from time to time. I prefer the Delco 42MT starter for the fit reasons described on my website.

Need any more projects to help you with your retirement, just let me know:D

Old Marget_ What is your web-site? My D-4 7U has been in my pole building the last four years. Went thru the ritual, new fuel filters, new fuel bypass spring and nipple, numerous bleeding attempts and I think today the pony failed? How do I verify pony has a broken rod or broken crank.

Engine ran like a kitten when I parked it four years ago. I had a fellow helping me today and he thinks the governor detent is not releasing on the main engine.

My D4 is a traxavator will I have to remove traxavator metal works to remove pony. Is there an under carriage electric start too? I've got tools and some mechanical background. Do you offer electric start kits for sale to people like me? Live in Lapeer Michigan.

Thanks
Metisse1965

Hi metisse1965,
I have been following your posts.......tough break (bad pun)
The website for the starter information is img400.imageshack.us/gal.php?g=header4oq.jpg
No, I do not sell starter conversion kits, just supply the information for those that prefer to do it themselves. There are conversion starters available by others, tend to be a bit pricey but they are available. To my knowledge no one makes a complete kit which includes battery box, switches, cables, blanking plates and support for the main engine air cleaner.

What is the serial number of your tractor? If it is the HT4 model it probably does not have the starter hole already bored in the bell housing. This would be a big job on the loader and require frame removal to bore in place or removal of the engine and bell housing to machine the starter hole. I do know
the direct start conversion will fit these models.

On the pony motor:
I believe it is possible to get the pony out without removing the loader frame when the loader arm is raised and the cylinder disconnected but I don't know for sure and to my knowledge there is no service manual info on how to do it.
Others comment please:)

Checking for busted rod or crank was already covered by edb. Unfortunately it is quite common for these things to throw a rod. Busted crank is a little more rare but does occur. The loader application is the toughest one of them all to work on.

Stuck fuel rack is also quite common for machines that sit idle for long periods of time or moisture is a problem.

Hope I answered all your questions.

My D4-7J 4256 has an operating pony and a 12 volt direct starter. In the winter I use the electric to start the pony, let the pony warm the main and away I go. Rest of the year the 12volt direct starts the main. If the pony was toast I would look to the electric but then add some way to warm the block.
I also have a D6-9U 27222 that is 24 volt direct. It starts whenever.

Hi Bob,
Good combination. Does the 9U have the glow plugs?

Can the D4 7U heads be machined for glow plugs? I looked at mine and didn't see bosses or anything else, just the injectors.

The pre-combustion chambers are the glow plug mount. Requires the late 1H7657 cylinder head that uses the larger retaining ring. Sr #19771-up or machine earlier head to accommodate.

I took option #3. My D4 2T had direct electric start added and pony motor was removed. I added electric start pony which I bought from a fellow BB for $500. When I got my D2 5U, it had a electric start pony. Direct electric start works so nice for me so I decided to add direct start to the D2. My local Starter/Generator shop sold me a rebuilt MT40 core,a new pinion drive,and a used adapter nose for $387. I built a drill fixture from Old Magnet data. (imageshack). The 3 5/8" hole was made with a hole saw using a 1/2" old Black & Decker drill.

I know that some have located the starter position by aligning a starter fixture to the Boss on the casting, center punching for the bolt holes and drilling a series of small holes for the 3 5/8". It worked well for them. The large hole on my D4 looked like it was cut with a cuting torch. It took some reworking of the large hole and the bolt holes in the starter flange to get a clean fit.

Add pictures

I will try again to post pictures.