1. Too many reasons on go F and R to tell you right off.
2. One is for engine oil, the other for transmission fluid. Engine oil will have small hoses, trans will have larger hoses.
3. Hydraulic- Sitting on truck looking fwd, right side of of frame is the hydraulic tank, with a black plastic breather cap.
If original could have a metal dipstick attached or newer versions a plastic one.
Fill hydraulic oil in where cap removed from.
Engine is probably a Y112 Continental flat head. Sitting same position, a typical engine oil dipstick left side, lower,
in block, reaching down into the oil pan. Use straight 30W name brand engine oil.
Transmission check and fill is down behind the mast/upright, into the front of the housing, about centered between the wheels.
It will have a little cross piece on top, twist if left to loosen, pull up and out. It consists of the top cross piece, large rubber plug,
and an attached dipstick. Loosening it lessens the size of the rubber plug, pull out and check level, wipe, replace, twist right to
expand the. rubber plug. Add slowly (1 quart at a time) as the housing tapers with height and it is easy to over fill and difficult to get out.
Next post question: Any name brand Dexron I or II transmission fluid. Originally used I, the later II. Either will work fine.
Now.... Disregard the go - no go for now.
Crank and run the mast all way up. If it goes up smoothly and bumps out to the stops, and engine loads up, you have plenty of
hydraulic oil. That is all it needs, to go all way up.
If it gets part way up, begins to jiggle and jerk, you need more oil.
Lower it slowly to expel any air in the circuit. With it all way down,
you can consider checking the level with the dipstick on the cap.
Add small amounts (1 quart) at a time. till it goes all way up. That is enough.
Depending on the installed mast, you need little oil for a single stage and a lot for
a three stage.
Post serial number of the truck, and the upright number (on outside of mast outer channel)
usually about eye level. Truck SN should read like C500-30 355-XXX-XXXX. Upright will be
something like F-83-130 or M-83-189 (xxx and XXXX will be numbers.)
Luck...