I'm working on an RD4 for a friend of mine and I need some help. Its a little different than my D-7 and D-8!
The serial number is 4G1993. He says its a 1938 model, but the name had changed to D-4 by then. What year is it really?
The pony clutch won't stay engaged and neither will the pinion. It looks like you can adjust the clutch through the pipe plug on top of the clutch housing. Is there supposed to be oil in that compartment? If so, what kind?
How do you get to the pinion to adjust the latches? Do you have to take the clutch/transmission/steering clutch cover off?
Where do you check the oil level in the main transmission?
How does the oil get to the main clutch release collar? Is it pumped through the tube from the trans. or is it splash?
I need to take the mag off the pony. Where do I find the timing marks?
I could answer most of these questions myself if he could remember where he put the manual, but I doubt that will happen, so any help will be greatly appreciated.
Thanks.

Well I'll give you a couple answers, 4G1993 is 1936. I use 30w in the pinion clutch compartment.
Timing marks on the mag are accessed thru a pipe plug on the backside of the magneto mounting flange.

Do a search for each of these topics on the acme board. Most has been covered in detail.

Matt

Thanks for the info. Matt. I searched ACME for a couple of hours and didn't really find what I needed. I probably need to try different key words. I pulled the pipe plug behind the mag and didn't find any marks when the timing mark was lined up in the window on the mag. I'll play with it some more this evening and see how many more questions I can come up with.

I don't have any specific information for the RD4, but here goes...
The pony pinion clutch must be too tight if it will not snap in and stay in. If it is too loose, it hasn't got much snap and it may not turn the main engine. That being said, don't get it too tight, they don't really require a lot of snap like the main clutch does. It's one of those pry out the locking pin and tighten or loosen the adjuster a notch and let the pin drop back in type things. Hard to do through that plug, but that's how it has to be done on the old ones before the ones with the bolted on access cover.
www.acmoc.org/ACMOC_BB/showthread.php?t=...light=timing+magneto

Main clutch engagement collar lubrication would be by a drip cup arrangement I believe. Should see a spring loaded flip cap on a small oiler over the clutch area. These usually dropped the oil onto a sponge in a shallow resevoir that slowly oozed it into the release collar. Could be a grease zerk, like the later (Larger???? tractors) There should also be a grease fitting on outside edge of the flywheel to grease the pilot bearing.

The pinion latches are adjustable through a small cover usually located on the left side of the clutch housing under the floor plate or next to the left brake. Remove the cotter pin, tighten down 1/4 turn and replace cotter. Repeat for the other side. Then test run

Magneto timing discussion here
www.acmoc.org/ACMOC_BB/showthread.php?t=...light=timing+magneto

I tried looking up some of the topics since I went through most of the same questions a year ago. Can't find them now. Do have the book so I'll brush up and get back to you.

Main clutch throwout is lubricated by a drip cup located between the steering levers.
Matt

Thanks ccjersey and SpragueM.
I would have thought that there would be a removable cover to adjust the pinion, too, but there's not. There's a hump cast in to the flywheel housing for the pinion, but its not removable. The top of the clutch housing, the transmission and steering clutch covers are all one big piece.
This Cat has a funnel over the release collar (inside of the housing) and an oil line that runs into the funnel from the transmission. I'm wondering if oil is supposed to be pumped through the line by the transmission, or if the transmission gears are supposed to splash oil into the line. If you guys can find more information for me, I'd sure appreciate it.

Transmission level is checked by a plug. Plug is located on right side of tractor, just forward of the rear sprocket on the access cover. Kinda tight as you are between the track, sprocket and carrier frame. A bit of a reach to get in there, but it's possible.

You should have a large drip cup in front of the gear shift quadrant, between steering levers. that cup is attached to the oil line under the clutch access cover. Also 2 smaller cups just in front of operator seat. one to lubricate each steering brake.

Pinion is adjusted thru that pipe plug hole as CC stated. No cotter pin though, a small pin is pulled back, pinion rotated and pin pushed back in to hold adjustment.

Thanks SpragueM. I've been sick the last few days, but I'll get back to working on the little Cat this weekend.

The main clutch bearing lube arrangement sounds like a one of a kind. Would you mind putting up pictures if you get the cover off working on the pinion latches?

Sounds as if it might work ok. It wouldn't take a lot of oil out of the transmission if there was a slinger on something that kept a little oil coming through that tube into the funnel. I would make sure that a little bit of transmission lube kept accumulating in the bottom of the clutch housing though! Don't know how you would check it otherwise.

I reread the procedure for adjusting the pinion clutch on the old ones and you only have to pry out the pin working through the fill plug hole. While you have it held out, you rotate the pony flywheel to turn the pinion and make the adjustment. I couldn't see any way to get a second tool in that one hole to turn the pinion, but you don't have to do it that way.

I didn't get much done on it today. I thought that spring was here when I started tearing it apart outside the shop last week. If I had known that winter would be back today, I would have put it in the shop.
I guess that some of the older Cats didn't have adjustable pinion latches. I only have a 6"x6" hole in the top of the clutch/trans. cover to work through, so I'm going to see if I can see the pinion with a mirror. If its adjustable, I'll probably pull the whole cover off, if not I'll leave it on.
The magneto wasn't working, so I took it apart, but I couldn't find anything wrong with it, so I put it back together and now it works fine. I'll put it back on, with some new plugs and wires, then I can put it in the shop, like I should have done the first time.