Conrod Orientation

Hi all,

I am after some advice as to which way my conrods should face ?
Someone has been in the bottom end before!
When I was stripping the engine I notice that the left crank cheek had been marked with one dot & the right with two dots.
Here is my dilema, the conrod that came off the left cheek had been marked with two dots & the right rod had one dot.
Either someone installed the rods on the wrong sides or they have marked them wrong and realised the mistake and put them back correctly.

The factory mark \, that runs across the two halves of the bigend was facing forward on both rods. I am inclined to believe this is correct.

I am aware that the oil hole in the side of the bigend faces to the outside.
Any info to verify correct orientation would be greatly appreciated.

Sweenz

Yes the oil holes go to the outside.

I would say, if the crank has been dynamically balanced and or you're not changing the bigend shells, then perhaps the rods are handed and the marks are significant, but if it hasn't and you're fitting new shells I shouldn't think you'll have a problem.

Cash

Hi Cash,

The crank is stock balance as it came from the factory!
I have polished the journals as they mic up within STD factory spec.
I am fitting new Bigend shells & just want to be sure the rods are the right way around with regards to the factory index mark across the 2 halves of each bigend.

Sweenz

Hi sweenz,

As long as each rod and cap are matched with the cap fitted the right way round, and the oil hole on the out side you shouldn't have a problem. Don't forget to use new nuts.

Cash

I mark my crankshafts and rods the same way. The dots on the crankshaft are usually paired with similar dots on the flywheel, to make sure the flywhweel is not reversed when you reassemble the crank. The dots on the rods are just there to make sure the caps are not switched between rods. Like cash said, as long as the oil holes are pointed out, it doesn't matter which side the rods are on. If you aren't replacing the rod bearings, then you would want to keep the rods on the same journals when you reassemble the crank, but with new bearings, it makes no difference which side they are on.

Ken

Thanks for the replies Cash & Ken,

I will fit the rods so all marks (dots) are a match with their respective crank halves as I am fitting New Bigend Shells.
That way after I am dead & gone, if someone else is in the bottom end they won't be scratching their head
trying to figure out who the F#*K Wit was that mismatched the markings & have to figure out which way it realy should be, like I am now!

The flywheel and right crank cheek had a corresponding punch mark before I separated the crank for cleaning, so that is all good.
New Nuts for Bigends are in the packet waiting to go on the rods!
I did buy New rod bolts but they turned out to be the cheap knock offs, so I won't be using them. I'll stick with the original bolts!

Thanks to you guys responses; I can now go ahead and assemble the bottom end without wondering if I got it right!

Cheers
Sweenz

Sweenz said:

Hi Cash,

The crank is stock balance as it came from the factory!
I have polished the journals as they mic up within STD factory spec.
I am fitting new Bigend shells & just want to be sure the rods are the right way around with regards to the factory index mark across the 2 halves of each bigend.

Sweenz

Click to expand...

I am curious, did you do the polishing? Can you put up a couple of photos for us?

Hi T95,

I did the polishing, sorry no pics taken & bottom end is now together.