1959 RD-21 35HP Johnson PARTS? Hard to find

[Turbosl2]

You guys have been a big help so far. My findings show the top cyl needs a rebuild. 30PSI, compression ring is stuck in the piston, bottom rings are broken in 2. Some scores in the cylinder walls. I am looking to bore it .020 or .040 over, install new pistons and rings...however, I cannot find parts for this thing!! I can find parts for a 1958 35HP or 1960 40HP. Any idea if the 1958 parts will fit the 1959? Or does anyone know the part numbers for oversized pistons and rings?

Thanks

 

[Turbosl2]

If someone who rebuilt a RD-21 knows about the interchangeability i would greatly appreciate your expertise.
Thanks

 

[Chinewalker]

Pretty much the same motors...

 

[Turbosl2]

Pretty much the same motors...

So you think a 1958 piston would work. Do you know the bore size? I measured about 3.0625, but this is not a mic, it's def larger than 3" and I thought they were 3"

 

[Turbosl2]

No Title

null From a 1958 evinrude on marine engine website

 

[Chinewalker]

Yes, pistons from 1957 to 1959 will work. Use the latest style rods you have, as they improved the wrist pin bearings from year to year. 1960 they went to the 40 hp which had a larger bore. Original bore for the 35 was 3-1/16", or 3.0625, so your pistons should be a few thousandths smaller.

 

[Turbosl2]

Thanks so much, this was exactly what i was looking for!!