Reply to Chris B. Weilep:
Those older Cats used straight 30W Series 3 Motor oil. In winter if the days are below freezing you can use 10W
Avoid using multigrade oil, (LIke 15-40), in warm weather. These machines were designed with tolerances for straight weight oil. Multi grade oile gets too thin in really hot weather. Multi grade had not been invented back then. The best oil of that type I have ever used was Cenex 518. There are other makes of course, but that is the best I've run across. This is also the oil to be run in the pony crankcase and transmission as well as the main back bevel gear case and main transmission. High grade Series 3 oil in all compartments except the final drives is what Cat recomended. 80-90W for the finals
Hope this helps
Chris
Make sure the plugs are good in the pony. Use Champion UD16 or hotter. Cross it to Autolite or AC for better plugs. I prefer AC
These old birds can be very tempremental, usually because the compression is lower because of wear. Try giving the pony air cleaner just a breath of Starting Fluid before or during cranking. Be quick on the trigger......just a VERY small amount.
Make sure the plug wires are good. New plug wires and new plugs every other year should be considered.
Be very careful with Mag cover and make sure the gasket is in one piece and in good shape. The tiniest bit of moisture will keep you cranking with no luck of starting it. Also inspect the inside of the cap for cracks. If there is ANY moisture on the inside of the cap, it won't start.
Make sure there is no crap in the line between the sediment bulb and the carb. If you're acumulating rust, take off the pony gas tank and put some nuts and washers into it and shake it to clean it. That will loosen any rust acumulated over time if the Cat has been sitting. Then flush it with solvent or gas several times and drain acumulated rust.
Hope this helps also
Chris