Connecting rod direction


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By 55 GLASS TOP - 9 Years Ago
Hello, I know that when the piston is installed there is indicator or notch facing front. Is there a right and wrong direction for the connecting rod when assembling the parts for installation . I hope I am being clear thanks in advance.
By 57RancheroJim - 9 Years Ago
Yes, the locking slots in the rod and cap for the bearings has to go to the outside of the engine. #1-4 and #5-8 will assemble on the pistons opposite when the piston notch is facing forward.
By 55 GLASS TOP - 9 Years Ago
Thanks I knew there was some kind of direction
By Ted - 9 Years Ago
Jim is correct.  I will add the following just for additional information.
 
For the stock Ford Y connecting rods, putting the tang side of the rod so it points to the outside of the engine or away from the camshaft would be correct.  This is not true for all engines though as some engine families install the rods so that the tang faces the camshaft.  To insure that the connecting rod is being installed in the correct direction on the journal, look at the bearing which will be offset within the rod bore.  The rod will be installed on the journal so that the bearing is moved away from the journal’s edge or crankshaft fillet.  This will essentially have both connecting rods on a journal with the two bearings moved towards each other.  On occasion I do find rods that are numbered either on the wrong side or both sides at which point you must look at the bearing placement in which to correctly install the rod.  I have on more than one occasion also come across connecting rods with tangs on both sides which is just something else to watch for.  Inadequate rod side play and/or excessive wear of the bearing against the journal filet will occur if V8 connecting rods are installed backwards.  I trust all that made sense.
By 57RancheroJim - 9 Years Ago
Good point Ted, I should have mentioned the bearing offset also.
By 314 - 9 Years Ago
ted i have a question i always wondered what would happen with a rod in backwards.these rods have a squirt hole to oil the cylinder wall.with a rod backwards it wouldnt get oil what happens to the rings and walls.
By 57RancheroJim - 9 Years Ago
Considering many engines don't have oil squirt holes I'm not sure if they are really over kill. You can't put the rods on backwards, the edge of the bearing will ride against the fillet radius on the crank throw forcing the rod toward the center and against the other rod and things will bind up.
By Ted - 9 Years Ago
314 (1/6/2016)

Ted.  I have a question. I always wondered what would happen with a rod in backwards. These rods have a squirt hole to oil the cylinder wall.  With a rod backwards it wouldnt get oil. What happens to the rings and walls.

Jim is correct in that the connecting rod installed backwards on the journal will have the bearing riding on the journal filet.  If the backwards installed connecting rod does manage to rotate on the journal (which it might if only one rod is installed backwards), then the rod bearing will be wearing heavily at its outside edge.  As far as the oil squirt hole goes, it will still be spraying upwards but if installed backwards, it will be spraying towards the other connecting rod instead of the cylinder wall.  As has also been brought up, many engines do not have a direct provision for providing oil to the cylinder wall but instead simply rely on any residuals coming from the sides of the rods.