Rod Piston Assembly

Pretty straightforward fitting each rod to a piston and since these pistons don’t have a vertical slot the rod can go either way.  I added a bit of blue threadlocker and torqued the nuts using the old shakefree washers which seemed to be in good condition – and likely better than the ‘made in China’ units I would have replaced them with.

When doing the assembly it does matter which side the slot faces when you put the pistons in the bore.  The manual says the rod clamping nut should be on the same side as the slot so I put a line on the piston to represent the slot.  During reassembly you need to have all the piston slots facing the left side.  That sounded odd to me.  I would have thought that the slots should face outward or inward.  But after thinking a bit I believe the slots all face one way so the oil holes in the rod bottoms all face the same way.  This is likely needed because the rotation of the engine will cause all the spurting oil to go upwards towards the pistons.

A little trick I picked up somewhere in my past.  Bits of hose over the threads to keep from accidentally scoring one of those carefully polished journals!

I put two rods in place at a time so that when I torqued them down they would hold against each other rather than trying to twist the bearing material.

I did have to lock the crank once again so that there would be no movement while I tightened the rod caps against the plastigage. Any movement at all destroys the results.

Here is the plastigage results from one of the rod journals.  It is between .0015 and .002 which is in range using .001 rod bearings.

Eight little pistons all in a row.  All I need now is a replacement ring for the top ring I broke earlier and I can finish the piston install.

Good news from Total Seal High Performance Piston Rings in Phoenix, AZ.  They have Studebaker 289 top rings on the shelf.  So I have ordered three – one to replace the broken one, one in case I break another and one for the shelf.

Next I’ll have a look at the oil filter housing and the oil pump.

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