Reply To: Power Head Cross Reference for 1958 Evinrude Fisherman 5516

[Don]

Standard bore on this engine is 1.9375″ (1-15/16″), so I’m guessing your engine is still standard bore.  Measure your pistons as close to the bottom of the piston skirts as possible.  As you say, the pistons shouldn’t fit in the bores if your measurements are correct.   So, I would order new standard OEM rings and recheck the end gaps.  Maybe a light honing will remove any debris that might be closing the ring end gaps, looks like minimal ring end gap is .005″.

Were the alignment pins messed up before you removed them?  If so, someone has been inside before you, perhaps they repainted the powerhead.  The engine did not come with washers under the rod screws, those steel lock plates should have been in place.  It is for these reasons I feel someone had the powerhead apart before.  Nonetheless, I feel confident the crank is OK and two new rods will solve the fit issue.  Make sure the new rods come with those lockplates, they can be ordered separately if needed.  The little lock rings that hold the wrist pins in place on the pistons should be replaced also.