420 Oil Pump

[Pistonman]

I am currently rebuilding components and have a question about the oil pump. Every thing looks good in it,( spring was worn on one side, and there were no shims). I just got a new relief spring and two packs of shim washers. (I was not sure if they still came 3 to a pack and they were only .29 a pack.) I still don't have the SM 2013, only an SM 2019, and the oil pump is not in it.
Anyway, the parts book says 2 shims are used "typically". I really don't want to have to pull the pan after I get the crawler built, to adjust the oil pressure. So does anyone have experience with proper shimming of the oil pump relief? Anyone use a new spring?

[Pistonman]

I guess I will put two shims in with the new spring and hope for the correct oil pressure.

[Ray III]

You could always put the oil pan up with only 4 bolts and no gasket and 2 quarts of oil to start the engine and see if the oil pressure is right.

[Pistonman]

The spring is rated at 45 lb/in. I don't have a spring checker to see how much pressure it would take to unseat the poppet, I think the lb/in measurement would say it takes 45lb to compress it 1 inch.
Another oil pump question I now have is, what is the clearance between the shaft, drive gear and housing. (End play) Edit to add: The parts book does not show any shims to adjust end play.