Another Kohler K301 Rebuilding Question...

[Polaris2007 4]

Okay guys, so there is this hole in the conecting rod end cap. I assume it is to let oil get to the crank pin to lubricate the bearing surfaces. The connecting rod will install either way, with the hole on the leading or trailing side of the rod as the rod comes down and around to bottom dead center. I ASSUMED but do not KNOW that the hole in the end cap should be on the leading side of the rod as it comes down to bottom dead center, so it will act like a "scoop", and force oil into the hole. Is this the correct orientation of the endcap/rod? :)

[TT-(Moderator) 1,147]

The oil hole faces the camshaft.

[Polaris2007 4]

Okay, so my reasoning was right on.....BUT, I was looking at the engine upside down and sideways, and I figured the engine rotation wrong. So I got the oil hole on the other side from the camshaft. Funny thing is that When Ioriginally took it apart for the rebuild, the oil hole was on the wrong side! I guess that is why it knocked so bad!

So I pulled the oil pan back off. Do I dare to just remove the rod cap, twist the rod 180 degrees and reinstall the cap? I'm worried that if I do this, I might mess up the staggered position of the piston ring gaps. Is this a legitimate concern? Should I pull the piston out and then flip the rod so i know the rings are staggered correctly? :USA:

[TT-(Moderator) 1,147]

http://www.asberry.net/files/TP-2379.pdf

Pull it back apart and do it right. The piston needs to go in with the mark facing the flywheel, the rod cap marks need to line up with each other, and the oil hole goes toward the cam.

Make sure you also generously pre-lube the cam pin and lobes with assembly lube or at least good clean oil.

[FarmerJim 5]

T.T. is right on the money pull it back down and start over, sure beats the end result if you don't :)

[Polaris2007 4]

Okay guys, you're right......I will pull it apart and start over. The piston is an aftermarket one with no "fly" mark on it or any other mark of any kind. It is completely symetrical. I'm assuming that since it is not possible to differentiate one side of the piston from the other, that it can go in either way? :)

[Coadster32 793]

Just from a machinst point of view, the rod cap is bolted on and machined with the rod in one unit, so the bore comes out perfect. You might get lucky and be able to flip the cap over, but is it worth the chance? (that is your call to make)

[TT-(Moderator) 1,147]

since it is not possible to differentiate one side of the piston from the other, that it can go in either way?

In this case, the answer is yes.

The arrow or "FLY" marking on the top of the piston was there so the people on the assembly line could quickly see which way to install the pre-assembled piston/rings/rod into the cylinder and could guide it in "square" with the crank pin.

[rick 245]

Another shining example of what happens when you work without the manual....

They are not that expensive, and full of information.

[Polaris2007 4]

I am working from the service manual......I just couldn't find the part about the oil hole. :)