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TR2/3/3A Distributor drive shaft play

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sp53

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Distributor drive shaft play, I use to just slap these things together and call it good. But this time I am second guessing myself, perhaps too much. Anyways, after I installed and reinstall the shaft a few times to get the pointer on number TDC, I noticed the distributor pedestal would not go down enough for me there is about .030 gap between the pedestal and the block. I can cut some gaskets out of a heavy paper and make the gap say.050 and that would give me some float, but I just do not like the amount of filler/ gasket shim I have to use.

This engine is a culmination of parts collected and at one point the brass bush was removed. I checked and rechecked that the brass bushing was bottomed out, and I check that the end of the two matting surfaces (the gear and bush have no foreign matter on them) but having to install say.040/.50 shim gasket concerns me. What could go wrong? Too much friction on the oil pump—not enough pressure on the oil pump and it knocks, and I pull my hair out. Or will the surfaces mate in after a few hours and I can recheck the clearance? Or that is the way things are suppose to be.
 
.030" is too much to run-in. It almost sounds like an extra thrust washer is stuck to either the gear, the block, or the inside of the pedestal. Have you tried to install without the shaft, to see if it is the gear that is too tall...vs the shaft not sliding freely down far enough?
 
You do realize that the workshop manual talks about measuring that clearance, and adding shims? .030" does seem like rather a lot, but they give an example that requires .011" to achieve the specified .005" (+/- .002").

I've never had an engine that needed shims, but when in doubt, following the workshop manual is usually a good starting point. In other words, I would add shims to get the .005" clearance, then re-check after you break in the cam.
 
I will try that John. One thing that confuses me is where the top of the gear meets the pedestal. I understand that there should not really be any meaningful contact there, but at some point that place is used like a trust washer or a contact surface of some kind. I was concerned that maybe there was paint on the base of pedestal and that it was binding before it went down, but I cleaned it up and it still sticks up too high and I tried another pedestal and had the same results. I can see that the shaft is lower than the split pin at the top of the gear and one point when I had the shaft out I had the shaft bottomed out on the split pin at the end of the gear, so I doubt if the shaft is the problem, but I am not sure. Like you suggested the gear just sits too high up. I might not be tightening the two bolts down tight enough and that would less the gap, but I like things to go smooth and not have to be forced. I will check the torque specs and see if it snugs down.

Just saw your post Randall and yeh some wiggle room for sure.
 
Well I torqued the two bolts down to 18 pounds and now get a reading of .011 so I guess that should work out if I shim things to .015. The pedestal is a tight fit and I did want to force stuff plus I think there is some paint over spray on the inside of the block. They probably put everything together and then paint.
 
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