460 freash overhaul timming issue-follow up info

If some of you remember my last couple posts I have some follow up info on my oil pump/timming issues. I pulled the oil pump and found that it is was worn in many spots. The most interesting find was when I removed the gear from the oil pump shaft which rides the cam shaft. I found that the solid steel pin used for holding the gear on the shaft was bent in an odd shape --a light v shape. Then I looked at the woodruff key for the same gear and it appeared when it was installed the key had too much stand out and the gear was forced on over the shaft anyways. It looks the key was holding the bottom of the gear out and the pin was forced in which bent the pin because the hole in the gear and shaft did not line up. This no doubt made the gear run kiddy wompus off the cam and wore out the dist/oil pump and the dist hold down which is pressed in the block. The one question I have is: since the oil pump/ dist shaft was worn down by about 1 hundreths and the hole in the dist hold down part seems to be worn larger by 4-5 thousands what should that dist hold down inside hole size be? Does anyone have any specs for the hole size of that press fit part where the oild pump/dist drive shaft rides? I'm going to implement shop where they work on Ih mainly and they said they would pop one out of a parts tractor for me. I would like to know if what I'm going to get another worn out one or not. I guess if its a tighter fit than the one I have that's better than nothing. I'd still love to know what it should be tho. I cant find anything even covering that part. The mechanic at that shop said they have never heard of one wearing out and never check it when they work on the oil pump/dist. I guess I'm now overly concerned but I dont want to touch it again in the near future or ruin another oil pan gasket and a day of work. Sorry the post is so wordy!

Nolan, Well done diagnosis. This has been an interesting (for the Forum) and frustrating for you issue. I also have no clue what size it should be in inches. I will indicate that there is reasonable and historic evidence that the replacement will be only moderately worn, and not a problem. I would measure the new components and if the difference between the two sizes is between .002 and .006 I would accept that as OK. When new it might be in the area of .001 to .002. (a guess based on sizes in other distributor drive gear to housing measurements, and reasonable expectations.
Someone cobbled the gear back together with either the wrong key, or a chip of incompressible material under it. Poor workmanship. May the pulley replacement go well, and the distributor not wobble. In my experience, I would put it together with the good pump and new hold down bracket adjust the static timing, and tighten it up. Do not loosen the distributor ti "see" if it wobbles.
Cam angle variation is the enemy. Use a timing light on the pulley with the pickup placed on several of the plug wires in succession. Look not for the timing mark, but for the image in the flash to be solid and not jumping around forward and back. The solidity is an indication of pretty good timing stability. A distributor analysis machine (Sun or other old machine that uses the distributor out of the vehicle) will be the best for accurate analysis of cam angle variation, and dwell. Call around to find one being used.
An oscilloscope will also do it if the operator is an artist with it. Best of luck, the answer is in hand. Jim

Can't say for sure, but is the hole for the roll pin drilled off center on this unit. I know some of the oil pump/ distributor gears/ shafts had the holes off center. Just a thought.

(quoted from post at 15:34:19 11/15/11) Can't say for sure, but is the hole for the roll pin drilled off center on this unit. I know some of the oil pump/ distributor gears/ shafts had the holes off center. Just a thought.

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I've worked on a few like that. The holes are purposely drilled off center to create an "interferance" fit for the pin. The intention is to keep the pin from falling out.

I can see why that would make sense and is explainable. I think the combination of 60 years of wear on an oil pump, a forced pin and a gear not centered would wear stuff out. My new oil pump is suppose to show up in the morning and I hope it will correct the issue. If the timming is not corrected by the new pump, reman dist, I dont know where else to turn.