It makes no difference if the #1 cylinder is at TDC for the distributor. The distributor should still drop down no matter what and in any position.

I agree with Griff. It sounds to me like you may be off a tooth on the distributor.

Also, some of the stock balancers had timing marks at 0*, and 30*. Watch for that too. You might be trying to set base timing at 42* instead of 12* if you were looking at the wrong timing mark.

Just on an off chance......these motors both turn the same way? I have counter rotating Merc 454's and the distributors turn the same way but they fire the cylinders backward. ie,normal firing order is 1 8 4 3 6 5 7 2 and reverse motor is 1 2 7 5 6 3 4 8. You can see where the timing would be different but close at the same time.
Just a thought.

I do understand the oil pump drive comes off the distributor, that isnt the problem, I have had the engines out for 3 sea trials, and had to set the timing by hand on this engine, the mark was about 30* off. It tells me the rubber in the damper has probably failed and the outer has slipped. I have heard of this but just never had it on my own engines.

My 28 has just poor access to the engines, it makes service very very difficult. Thanks to you guys I do have a short list ideas on how to check the ballancer this weekend.

These engines are standard rotation, the TRS drives handle the counter rotation