First off, thanks everyone for whatever knowledge, advice, etc. you may give. I will/do appreciate it!!! So, here we go.......I've never owned or even driven a dozer before but I bought a 1946 D6 5R at a reasonable price just outside of Peoria, Il. where it was made, guess that's why I own it now. Anyway, I know absolutely nothing about this or any other Cat but would like to learn the ins and outs so to speak. The fuel filter, injection pump and governor were off of it in pieces, supposedly all the parts are there. I'm guessing SOMETHING is missing. The pony motor is missing the rod and piston from what the previous owner said along with the mag and exhaust pipe. I have done some research on it but I don't know what the correct mag would be for it along with tons of other things, anybody know what mag it is? The way I see it, I should get the filter, pump and governor on first (somehow, after cleaning/assembling) then address the pony issues. How difficult or expensive are parts to find? I think I read on this website pony and (maybe fuel injection?) parts on later D6's with the 318 will interchange to some extent. I don't know. I do have the original owners manual and a D6 9U parts manual that came with it. I'll have many more posts most likely but here's some pics in the meantime. Thanks everyone!  

 

Looks like a very tidy unit. Has a La Plante Choate blade on it similar to mine. Mine does not have the stays from the top of the blade.

There must have been a reason for pulling the injector pump off. As far as I know the injector pump on the 9U's D318 is different but I could be wrong. The only difference in the pony motor is the D318's pony has an electric starter on it.
How is the pony motor missing the rod and piston? It does not appear to be dismantled.

Thanks for the reply Philc. I was told the machine was running rough so the pump was pulled to clean with the injectors supposedly rebuilt at the same time.The previous owner said he reinstalled it but didn't get it timed properly and it either ran rough or not at all - can't remember exactly what he said. He also told me the pony motor "threw a rod" - whatever that meant - but like you, I don't see where it was taken apart. Maybe spun a rod? Hmmmm.
I'd like to start by putting the pump back together or buy a good used one. Whatever is the best option. Do you know anyone with parts I may need? Thank you.

I have some rod and pistons and magneto AMERICAN BUSCH CAT and more parts for D6-5R if I can help

Thanks gemdozer, I'll most likely need various parts I'm not aware of yet. Some pony parts and the magneto for sure. Not sure how we can contact each other than through this website?

gemdozer: I updated my contact info to show an email address.

get a copy of the parts book, service reference and owners book for your model and serial range. these are a big help. if your not a paid member of acmoc join us you get access to the magazine and tech library which is a huge trove of info thanks to the dedicated volunteers that keep it organised and the members submitting file scans to added to the expanding collection.

the dealers still have a number of parts for these older machines particularly gaskets, seals and bearings. the dealers may also be able to order pistons for you. but they need part numbers as they might not have the part book data anymore but they can search the parts database by part number.
as for a piston jp pistons in south australia can custom make pistons for many machines have a look on thier website they have a product list. it also might not hurt to give them a call. there maybe another engine that uses the same size and style of piston. ive done that with piston rings no direct match but something else used the same size rings.

if the injector pump and injectors are there any good injection shop should be able to service that for you. many of the larger dealers have thier own pump room and injection techs and can do this work.

magnetos can be rebuilt generally its a set of points and a condensor maybe replace the bearings.

the pilot engine exhuast manifold could be unobtainium i know the u series d4 ones are not available new.

there fairly simple a exhuast shop should be able to make you one.
dont forget to check the bit of exhuast tube that goes through the intake manifold as they often rust out this will prevent the main from starting and can lead to a dusted engine. hence it important to have working rain flaps on the exhuasts or cover them with a tin. another collector showed me a trick use spin-on oil filter bodies. he got a old spin-on filter off his truck and cut the thread end off and it works a treat as it's rounded on the end it doesnt hold water unlike a jam tin.

I have a 1942 4R D6 that I'm rebuilding the pony and main engine for. Your engine is a D4600, same as mine. A great source of information is Squatch 253's playlist of his rebuild on an early model D2. While his engine is smaller, so many of the concepts apply. He gives very good info on the fuel injection system, particularly.

www.youtube.com/playlist?list=PLW_TtiTWG...-leidqLnhB35AX3g-XUE

Also, you'll want a copy of the parts manual and a copy of the service manual. I downloaded digital copies from Jensales. They're a lifesaver.

It's too bad Florin Tractor in Sacramento, CA, went out of business. They had so many NOS parts. The good news is most parts are still available through Cat.

Good luck!

Thanks a bunch sheddcanyon (and trainzkid88) for the info. I'll check it out.