CV740 ... metal shimmer in the oil, 1,500 hours

[fmorelli]

Got access to the rods. Top side definitely shows wear. This looks like where the aluminum shimmer may be coming from in the oil? I'm used to regular rod bearings so not sure how to read this - straight aluminum. Thanks!

 

[Rivets]

Definitely see wear on both halves of the rod bearings. Probably the source of your glitter. If I had it in my shop I would be replacing the rod. Everything else looks fine to me. Just my opinion.

 

[fmorelli]

Definitely see wear on both halves of the rod bearings. Probably the source of your glitter. If I had it in my shop I would be replacing the rod. Everything else looks fine to me. Just my opinion.

General consensus that I got from two other engine guys I know (though automotive).

I guess I'm pulling the heads so I can get these assemblies out, then, and change out the rods. Thanks for the feedback!

 

[bertsmobile1]

I would go one step further than Rivets and give to journal a quick light polish with Silvro , Dilute tooth paste or similar fine abrasive .
As all of the damage is on one side of the rod pay close attention to that side of the journal

 

[fmorelli]

Wanted to update this post. I replaced the rods with new. When I removed the crank I found the flywheel side of the crank bearing surface in the upper case was probably the aluminum culprit. I've attached some photos. I carefully cleaned it up (last two photos). I did not check clearance because, simply, at this point it runs until it hits the trash can so it doesn't matter.

Everything went back together, new gaskets. I decided to move to 5w-50 for a bit of viscosity help on the hot side.

Motor sounds great and is running well. We'll see how long it lasts - we're at 1,500 hours currently.

Why is there wear up here? I don't know as a fact. Oil does need to be pumped up to this bearing surface. Maybe oil ran low at some point. I was careful on setting the new upper crank seal (replacing the original factory installed seal).