Position of distributor rotor relative to engine position

[schnork]

I pulled the camshaft assembly and cylinder head off the engine and took these parts to a machine shop to be inspected (they were o.k.). The shop disassembled and reassembled the camshaft assembly before returning it to me.

My question presumes the engine is positioned with cylinder 1 at TDC on the compression stroke.

When the notch on the camshaft drive-gear is aligned with the mark on the housing, where should the rotor be pointing (spark for Cylinder 1? 2? 3? 4?)? It doesn't look right the way it is now (the rotor points a few degrees counter-clockwise from aligning with the notch on the camshaft gear -- is that its correct position?

Thanks in advance for your help.

[Razorback1980]

Not sure I understand where your rotor is pointing....but if the piston on number one cylinder is at TDC or relatively close and both valves are closed, then the rotor needs to be pointing very close to number 1 spark plug connector on the distributor cap. Same is true for the other cylinders. I can't remember the firing order off the top of my head, but check number one and then if you still doubt it, rotate the engine a half turn and look at the rotor again and it should be pointing to the next cylinder in the firing order. If you need, I'll look up the firing order for you, but you should easily be able to look which plug wire follows number one plug wire and then see if both vavles are closed. You can establish TDC for the cylinder by removing the spark plug for that cylinder and sticking a wooden dowel in the spark plug hole. You can also use a screwdriver or something like that, but be careful not to scratch anything. Let me know if that doesn't answer your question.

[schnork]

Thanks Tom for your help. Your info confirms what I've heard from other sources -- I might have gotten the "new guy" at the machine shop who seems to have perhaps left a bolt loose. BTW, Firing Order is 1-3-4-2.

[SoCal Driver]

Only one way-possition the cam goes back on the engine. Only one way-position the rotor goes back on the cam. You will bend valves if you don't have it all lined up correctly. It is possible to put the spark plug cables back on out of sequence. This has nothing to do with the cam-rotor-engine relationship.

[schnork]

Thanks, Hugh. It turns out that the bolt that holds the distributor driver to the end of the camshaft was loose, allowing the rotor to wander. I don't know if this was an oversight on the machine shop's part or whether it just worked itself loose. I moved the rotor back into position to fire cyl #1, tightened the bolt, and it's now running like a champ!

[SoCal Driver]

Good it was the bolt. Had me (us?) a bit concerned.