I took out the distributor to get at a socket that fell behind it and the firewall, and it refuses to seat in the same position it came out. In fact, it only wants to seat in one orientation, which moves as I turn the engine over. The distributor and drive gear aren't keyed, right? I'm sure it isn't, and it in no way looks like it is. But I have to ask, since it definitely feels like it is. I have a '71 Alfa Spider, and that does have a distributor drive that's keyed. Is there something I'm missing?

 

oil pump shaft down it the hole probably got bumped, Turn it with a screwdriver and try again.

 

It’s not keyed, but the oil pump drive shaft is like a key.
A long handle flat screw driver can be used to turn the pump shat so it aligns with coupler on distributor gear.
Also note the you have will have start installing with the rotor slightly retarded from where you want it to finish when fully seated, as the gears will cause it to rotate when installing.

 

Sounds like you have rotated the engine since removing the distributor....You will need to start completely over....First by getting the #1 cylinder on TDC and proceeding from there all the way to resetting the timing. I suggest an online search for installing a distributor on a SBC, followed by setting the timing on your specific year computer controlled timing advance.👍

 

To seat the distributer after spinning the engine over is a relatively complex, but not impossible process as mentioned above. This exact scenario just happened to me on my 1985 Corvette while removing the intake.

It would be essential, as a start, to reseach many of the existing video's on the entire process on setting top dead center (TDC) on #1 cylinder on a 350 engine, as already mentioned.

However from my recent experience, you will have to know and be sure that you are on TDC #1 Cylinder "On The Compression Stroke" on piston #1. I assure you that getting this absolutely correct will save you alot of time and effort as this is required before you even get to the distributer / rotor step. To ensure that I was on the compression stroke on #1 piston, I removed the #1 spark plug had a camera bore scope to see inside the block and watch the piston progress upwards as I was turning the crank bolt with a "flex head long bar ratchet" slowly by hand. Once I saw that the piston was going upward close to the top (this confiirmed to me that I was on the compression stroke). I then finally aligned the timing mark with the mark on harmonic balancer to achieve TDC.

Some of the videos show only how to achive top dead center (TDC) with the cylinder heads already removed from the block.

Note 1 - I did remove my driver side valve cover earlier on as a double check to ensure that I was on the compression stroke, but looking back now, it wasn't required.
Note 2 - A flex head ratchet simplified the TDC process for me as I had limited space to access the crank bolt between my radiator and Vansteel camber brace in which I preferreed not to remove.

https://directlift.ca/ratchet-3-8-dr...eC3ws88C6iq_S_

The distributer step will be the next step in which I'm sure there are videos on the process that likely already exist. Allocate time and extra patience in this procedure.

I hope this helps.

 

^^^^^^^ You may have got lucky (50% chance) or you are leaving something out but the description above does not guarantee you are on the compression stroke. You could have just as likely been on the exhaust stroke. Feeling for compression with your thumb/finger blocking the spark plug hole on #1 indicates the right stroke, not a borescope unless it also tells you both valves are closed.

 

Thanks for the message.

I had the driver side valve cover removed, which proved to me by the position of the intake/exhaust valves on #1 that I was on the compression stroke. "Feeling for compression with your thumb/finger blocking the spark plug hole on #1 indicates the right stroke" certainly is another way of confirming compression stroke, but that's not what I did as I was posting from my direct experience which was successful. Likely, there are other way to confirm the compression stroke too.

My intention here is not to rewrite the complete GM procedure manual here or replace some great and informative videos already in existance. My intention is to share from my experience on what I did and add some beneficial information to this thread. In my opinion, your comment does add value and information to this thread.