Hi all I have been working on rescuing this RD4 from a riverbank it has been parked on for about a year with your help I was able to free up the tracks and pull it to safety with an F350 and a 1948 8N but they could not drag it up the 16% grade half mile driveway to my barn. Then the guy next door had some logging done and a cat 543 log skidder became handy so for a $100 (beer money) they dragged it up for me in under 20 minutes.

Now the fun starts. It has been an Easter egg hunt for the parts various people removed over the years trying to get her going and dropped out in the woods
I am missing the intake for the pony motor and the mag was left in a puddle and the gears have turned to mush. The main can be turned by hand and the pony after a little persuasion turns free. The undercarriages look good. Your years of experience and some guidance in where to start with a project like this would be a great help. Where is the best source for manuals for this beast RD-4 #4G2448 and if someone has a picture of the pony top end (carb and manifold) I could sure use it.

Grayrat,

I see the intake is there. Missing is the magneto, carb, oil fill housing and governor. Will try and post a photo later.

Matt

While you are at this point on the pony motor, check and see if it has compression on both cylinders, slack in bearings etc. It's pretty common for them to have a little endplay on the crankshaft. If no compression, could be a valve and you access them under the top cover. The top cover has to come off anyway if you need to replace/free up rings etc on the pistons.

You're missing so many parts there, looks like your shortest (possibly cheapest) route is to find a complete pony motor and marry the two together. If yours' bottom end is good you may find one that has a bad crank etc that has all the parts you need up top. If this thing has been open to the weather, I wouldn't run it w/o opening it up and cleaning out all the gunk inside, assess everything and reassemble. You may get by with some head gaskets and a tube of silicone if you want to save $, but balance the cost against ruining a crank if it spins a bearing because of debris in the oil.

Sitting in the seat, the breather/oil fill pipe fits on the left port and has a connector over to the intake on the carburetor which bolts down on the right port. I guess you have enough of the exhaust manifold flanges left to ID the exhaust ports.

I would actually start with the diesel engine and rest of the tractor instead of the pony. If you can change oil, coolant, fuel filters etc, turn it over by hand a couple of times and pull it off to start, you can assess what else is wrong with the tractor. Lots of them out there being used regularly with ponies that won't run.

How would you eat an elephant? One bite at a time!

I found several more parts in the brush around where the tractor was stuck?
looks like the oil fill the govenor frozen of course the carb also frozen, whats left of the MAG and an exhaust manifold. It's not apparent where the carb attaches to the intake everything else makes sense

I could use an air wrench to turn over the main but what is the startup sequence? I'm looking for manuals like service, operator and parts but Ebay is not much help so I'll post in wanted section could someone run through a quick startup procedure and what the large and small levers are for in the attached photo?

Sorry, I couldn't read the captions you put on the levers. Look at this, www.antiquecaterpillar.net/ACF_v2/showthread.php?t=4670 about a D2 of the same era as your tractor, so it's similar.

www.antiquecaterpillar.net/ACF_v2/showthread.php?t=7592

you'll have to block off the water passages to run without the pony motor, but it'll be a way to quickly make some progress on the machine as a whole instead of waiting on the whole pony motor to be finished.

www.antiquecaterpillar.net/ACF_v2/showth...t=starting+procedure

is a discussion about checking out a "new" tractor. Last thing you want to do is rush to start something up and damage it because of water in the engine oil or a gear case. Some way of pressurizing the fuel tank may speed up the process of bleeding the fuel system when you don't have the pony motor on there. A piece of innnertube with the valve stem on it can be clamped over the tank opening and used to pressurize the system enough to bleed it after changing the filters/cleaning out the gunk etc.

Maybe a little encouragement or incentive is in order here:D
This is what it should look like when you are done;)
Belongs to Lou McMaster, a fine example of the model.

Whoops, forgot the picture

Thanks for all the help, keeps me from feeling i'm in over my head. I just found out the lower radiator housing is cracked by the drain plug. So now it's pull a part time and braze it up.

I got my books direct from Caterpillar...and I've also got an extra pony magneto and pony parts....

Geoff.
Priest River, Id

what shape is the mag in? email me <a href="This email address is being protected from spambots. You need JavaScript enabled to view it." target="_blank">This email address is being protected from spambots. You need JavaScript enabled to view it. and I'm interested in the top end of your pony as you can tell from the photos. I found most of the original but it's been left on the ground for years and not sure how much is recoverable

grayrat,

You will find the books you need on ebay - operators instruction, parts & service (engine D4400 and tractor), it will just take a while for the right books to be listed at the right price. Reproduction service manuals are available, if you don't won't to wait for an original caterpillar serviceman's reference book.

A friend and fellow Chapter 2 member owns 4G 2450.