my brother just bought a 91 3.1L and the timing chain is broke. we turned the cam to check compression. my question is how do i set the cam right to install a new chain. Any help would be great. Thanks Karl

 

on the top sprocket for the cam there should be a little dot. Have it point straight down. Then on the crankshaft's sprocket there should be a little dot. Have it point straight up. You should have them aligned properly.

 

one more question with number one cylinder at top dead center where should the rotor button be pointing? i know on a 350 it should point at number one cylinder.

 

Oh, when you do the cam you should be at TDC on cyl 1 also.

The rotor position is more of a reference for you to find so you can get the car to start. You can really point it anywhere as long as the rotor and the connector on the cap for cylinder 1 line up. That's why you have to play with advancing/retarding to find timing 100%. It's just a reference. I usually always drop mine in with it not facing cylinder 1 but with the back stud on the carburetor's driver's side.