Any Pontiac guys on here? Need insight.

pt70 said

Your photo of the shaft shows heavy scoring on the shaft. Note the smooth diameter of the last quarter inch. Also note the gob of metal stuck in the hole of the next larger diameter. This would cause noise.

Your first picture of #42 shows a casting defect resulting in a paper thin [and cracked] piece of metal. This may have caused the original problem?

good luck.

Click to expand...

The scoring on the shaft is definitely a red flag when I pulled it out. On the next biggest diameter is not a gob of metal in it, these are tabs that help from letting the shaft pop up through the hole. The Pontiac motors have these as the theory is to put the drive rod in the oil pump and then install the pump. Those tabs are supposed to keep it from moving up out of the hole once it's assembled, most people grind them off and feed the rod down from the top side.

The spot in the block where the casting is broke looks to have been that way for a long time so, I'm not thinking it has caused any of this but, ya never know.

I'm waiting on an oil pump primer rod to show up so I can run the pump just to see if it's quiet and check the volume of oil getting to everything. I'm also going check the alignment of the distributor to the camshaft. I wonder if the camshaft is not sitting in the motor correctly. I wonder if the camshaft is sitting too far towards the rear of the motor pushing so hard on the distributor that it has pushed the shaft on the distributor back causing a misalignment of the pump drive rod causing it to rub the block but, at this point anything is on the table.