Hello all,
I need help/advise on this subject urgently as i'm looking to rebuild my engine this weekend. The problem i have is that I have bought a second hand engine off ebay which still has a slight knocking to it. I have stripped this engine and everything has been replaced as i thought. Due to there being no visual damage I took it to my local engine remanufacturer to check dimensions and conrod straightness etc. They found everything to be ok but the con rods are handed and they were not in a uniform configuration.
We agreed that when I stripped my original engine, this would show me the correct con rod orientation. Unfortunately i had three snapped conrods and am not convinced of the orientation. They all looked to have the smaller notch on the conrod facing the rear of the engine.
Therefore my question is what is the correct orientation of the conrods??

A quick response would be much appreciated.

Thankyou in advance Jason

 

Sorry, wish I could help; however, I want to know when you find out.

Found answer see below!!!!

 

I found the answer. included is the verbal portion. If you PM me your email address I can send the entire engine assembly procedure.

AJV8 Engine Assembly
10
Pistons, Connecting Rods and Bearings
Pistons
The piston grade code stamped on each piston
crown must be the same as the cylinder block
grade code for the cylinder.
Any excess wear to the cylinder bore will be
evident by visually inspecting the Nikasil finish. If
damage to the finish is evident, the cylinder
block must be replaced.
‘A’ bank piston and connecting rod assemblies:
arrow on piston and thick flange of connecting
rod must face the same direction.
‘B’ bank piston and connecting rod assemblies:
arrow on piston and thin flange of connecting
rod must face the same direction.
Piston rings
Each piston is fitted with three rings:
• Top compression ring
• Stepped second compression ring –
install with step facing down
• Two-piece oil control ring
Install as shown in the illustration. Align piston
ring gaps at least 90º apart.
Connecting Rods
Connecting rods must be fitted to the cylinder
position marked on the rod and the cap.
Each connecting rod has a thick flange and a thin
flange. The thin flange side of the connecting
rod is also marked with a dimple adjacent to the
bearing. Connecting rods are installed on their
journals with the dimples (thin flanges) facing
each other.

 

almost all V8 and V12 engines go together that way, thin part of rod toward each other.

some V engines have offset crank pins, and they may be neutral or even on both sides, but still oriented to front(usually).

 

Bearing inserts are offset in the rod big ends. When assembled, the pairs of inserts must be closest to each other, This allows clearance so that the fillets on the crank-pin don't interfere with the insert edges.

KS

 

cammerfe, what you say is true in most cases, BUT some good engines use a rolled fillet and has no interference to the bearings shell.

the point of area were one could have a smooth transition from journal surface to the crank side face is rolled by a hi-pressure wheel, that has proven quite resistance to torsional flexing that could lead to stress cracks.

it actually tightens up the grain strucure of the metal,right where flex may exsist.

GEE Whiz i feel as tho im back teaching engines again.