So a friend of mine bought a decent little GS-R that the previous owner put engine honey in so we found out a few days later it had a rod knock when it finally seized.

I took it upon myself to do the engine rebuild, had the block hot tanked, honed, and decked and had the big ends checked for clearance and two of them bored back to OEM spec by a machine shop.

So onto the issue... has anyone else who rebuilt a GS-R noticed on the rod big ends on one side where the end meets the rod there's a "3" engraved on the side? Like it's halfway on the rod and halfway on the end so when you bolt them together they form an entire "3"

I used this to make sure I put my big ends on the correct way but when I finished I noticed there's the good old "P72" markings on the big end too... AND ONE OF THEM IS BACKWARDS!

So now I'm concerned about the origin of the "3" and which direction the caps go, what would be my best indicator? Should I take the caps back off and make sure the tangs for the bearings all line up properly?

 

Are the rod locks in the right location?

 

Bearing tangs are supposed to BOTH be on the same side... facing the exhaust side of the engine. This will always mean that the rod bearing identification/size number will be legible since half of it is on the rod and the other half is on the rod cap. Occasionally, the rods are cut at the factory with the rod backwards in the fixture, and thus, the raised three digit rod code (P72 in your case) could be backwards. So do NOT focus on that part... focus on the bearing tangs and which side of the engine they face.

Good luck.