Engine noise when not under load.

[calexican]

Well my Tom Joad Grapes of Wrath motor came together really nice. Drove it around a bit today and discovered that the rattle is indeed the transmission. At least I have a motor that doesn’t leak all over the place, and it’s nice and clean when I pull it to do the old crash box....a little tired of that noisy thing...
Any suggestions on an upgrade that would work with the stock 36hp?

[calexican]

[calexican]

So I got the eBay motor open. The offending noise is a worn rod bearing. The original motor I will open tomorrow, but I’m sure it’s offending noise comes from how loose the crank is. What’s interesting to me is how similar these two motors sounded in their signals that something was definitely wrong, this is what lead me to believe that it was transmission noises.

My question now is, do I replace the rod and bearing? Or would replacing just the bearing be enough.

[calexican]

Also noted that this motor seems to have 0 endplay.

[calexican]

So this is what my engine noise looks like.

And this was interesting...a homemade rod shim...

[calexican]

...and this what the other engine noise looks like...hence the too much overplay...

Correction, I thought there were only two shims, turns out two were oil stuck, so there were three.

this the eBay motor case

[calexican]

So my plan now is to use eBay motor case, replace rings, rod and main bearings...

Anything else? Should I use the rods from the old motor since the wear on the bearings is even? They are lighter than the eBay rods.

Any advice would be appreciated. Thanks.