1) You got that for a very good price. That's also a big red flag waving 911 911 911, to me anyways. Nobody gives things away unless there is a good reason. My money says he was having issues and said the hell with it. I see it has an aftermarket mickey mouse tank. That's the first issue. It's a gravity feed. Unless the carb has been fitted with a larger fuel needle valve under the float, your going to starve it of fuel. Also does the tank have a vented cap ?? If not you know the result, right ?? I am not a fan of over your head fuel tanks. It also makes the machine top heavy.
2) Do a compression test right away to see where you are at.
3) Do not even start this thing again until you have done a pressure/'vacuum test to verify seals are good and you have not air leaks.
4) Below is a list:
Here is my list of things to check on an oddy when you are doing an
Engine job or just purchased one.
1) Fuel - your fuel pump must put out about 4.5 oz/ten seconds approx and your fuel must meet at least the minimum octane rating in manual. I run straight avgas or you can mix it 50/50 with pump fuel.
2) Do the vent modification - use the search box above.
3) Check your stock intake manifold - they're 30yrs old and crack just looking at them.
4) Check your reeds, they must seal or you could get low compression reading on your gauge. Make sure your gauge is accurate.
5) Engine must pass pressure and vacuum test - if it doesn't don't even start it, find the leak. I use 10psi max pressure and 10in vacuum in my tests and it must hold for half hour minimum.
6) Rebuild the starter, it is a big job after the Engine is in.
7) Gas tank - if it's rusty inside get it cleaned and coated at a rad shop. If you look inside with a flashlight and it looks like the pickup tubes are rusted I would tap the tank drain plug and draw fuel from there. Both my machines are like that now.
8) Original fuel and pump vacuum lines are junk now after 30yrs so replace them.
9) Remove the drive shafts and make sure the u joints are good.
10) Check the wheel bearings.
11) Over fill the transmission -- put two quarts of oil in it. It's a splash lube system and the driven shaft bearing don't get any lube unless you are driving so don't rev it in the driveway all day long
12) Adjust your brakes - I set them (F & R) so I can feel a bit of drag.
13) If doing an Engine rebuild do NOT use the paper base gasket as it blows out. Must use the metal one.
14) Some good info here:
viewtopic.php?f=26&t=15392&hilit=danifold