440 Piston vs. Rod Orientation?

[PurpleBeeper]

I'm piecing together a "street motor" from a pile of misc. parts. What direction do the pistons go on the rods (say vs. the number on the rods or ?)

I know the notch (if it has one) on the pistons goes towards the front of the motor, but I bought some loose rods & want to help the machine shop installing pistons. "Somebody" mentioned that the rods should be oriented (say vs. the number) in a particular direction. "Somebody else" bought a motor only to find out after pulling the heads that the pistons were installed backwards. I'd like to avoid any problems.

THANKS FOR THE HELP!

 

[threewood]

Ok, I give. What is say? And bump for more knowledge.

 

[wagonman]

Yes to the notch pointing to the front of the block. The rods should have a chamfer that goes to the crank fillet. Might need some rod bearings installed to see the chamfer better. If the rods are installed backwards the crank probablly wont turn over.

 

[Bill Monk]

If you look at the rods on the crank end, there will be a small hole on one end of the rod. This is the oil squirter hole and must be installed toward the cam shaft. If you screw it up and install it backwards, all you will be oiling is the oil pan!

 

[Bill Monk]

Yes to the notch pointing to the front of the block. The rods should have a chamfer that goes to the crank fillet. Might need some rod bearings installed to see the chamfer better. If the rods are installed backwards the crank probablly wont turn over.

yep

 

[PurpleBeeper]

Yes to the notch pointing to the front of the block. The rods should have a chamfer that goes to the crank fillet. Might need some rod bearings installed to see the chamfer better. If the rods are installed backwards the crank probablly wont turn over.

Thanks, can you clue me in about what a "rod chamfer" is and also what a "crank fillet" is???

 

[PurpleBeeper]

yep

View attachment 558159

Thanks Bill, so the caps are on the rods I just bought, so I will check that the cap has is lined up "bearing tabs" on the same side of the rod (next to each other, but not on top of each other), but I'm still confused as to how these orient in the block? How do I make sure the pistons go on the rods the right way? I'm sure one bank vs. the other bank is backwards vs. each other (that's what I'm thinking anyway)

 

[Richard Cranium]

Thanks, can you clue me in about what a "rod chamfer" is and also what a "crank fillet" is???

If you bite it, a crank fillet will be a lot tougher than filet mignon.

 

[Bill Monk]

Thanks Bill, so the caps are on the rods I just bought, so I will check that the cap has is lined up "bearing tabs" on the same side of the rod (next to each other, but not on top of each other), but I'm still confused as to how these orient in the block? How do I make sure the pistons go on the rods the right way? I'm sure one bank vs. the other bank is backwards vs. each other (that's what I'm thinking anyway)

Correct, if you were looking at the block from the front, the notches on the pistons should all be facing you and the rod squirt hole should be facing toward the cam.

 

[Bill Monk]

one other thing, since you are planning to use these rods, I would strongly suggest you have a shop check them out. If the caps have been mixed up on the rods, you could have issues. Too much time and money to take a chance.

 

[Bill Monk]

Thanks, can you clue me in about what a "rod chamfer" is and also what a "crank fillet" is???

Thanks, can you clue me in about what a "rod chamfer" is and also what a "crank fillet" is???

 

[moparnation74]

Any experienced machine shop knows these basics....

 

[wagonman]

On the pic Bill posted you can see the chamfer on the bearing tab side. It is kind of like an angle that is ground into the rod,the other side is flatter and butts up against the other rod. A fillet is where the crank pin is cut. The older Mopar cranks had less of a pronounced fillet as compared to a Brand X. They say the Brand X cranks are stronger because of it but I have never broken a crank. You can check you rod side clearance when assembled to verify if the crank has been damaged in that area or if the rods are worn. My bet is that You will be fine. Google Crank Fillet.

 

[wagonman]

Excellent.

 

[69Bee]

Any rod can go anywhere when it is only a rod. These are the rules:

1) Piston notch, arrow, or a letter "F" fact towards the front of the motor
2) The rod bearing tangs ALWAYS face out on a Mopar
3) Driver bank is 1-3-5-7, Pass bank is 2-4-6-8

I will mark rods (on the tang side) 1 - 8. Then split them up odd/even with the proper ends facing up for front. Then I put a "F" on it with a sharpie. I put the pistons (well lubed pins) with the front mark out, then heat the pin end of the rod with a torch. Before you guys whine, a Sunnen rod heater does the same thing, and cheaper propane copies do too. Only heat the rod enough to install, meaning the first stage is blue, then a shiny straw (yellowish) color to a very dull red. Install with the "F" marks forward, and let cool. Do NOT keep heating until the pin end is cherry red, as you will buy new rods. It does take experience, and not too hard to get the hang of it. It is better to err on the too cool side, and not get the pin all of the way in. Then just use a press to finish it. I do not have the Sunnen piston fixtures (expensive and obsolete), so I do not press pistons on. If it is cocked, you will gouge the piston with the pin and end up with a rod/piston assy that will take out the rod bearing as it is too tight. On a last note, rod tangs out will ensure the large chamfer goes to the crank fillet. If you assemble two rods on a throw, and the crank locks up, you have a rod backwards. The fillet is running into the bearing locking it up. Hope this helps...

 

[383man]

All good info. As said the rods will have a chamfer on one side that goes to the crank fillet. One other way to look at the oil squirt holes is they squirt oil on the other bank cylinders and some at the cam. So the squirt holes as said have to face to the cam or I like to say to face them to the opposite side of the block so they will squirt oil on the opposite bank cylinders also. Ron

 

[Garys1969RR]

If the engine is assembled properly. the numbers on the rods (2-4-6-8) will both be visible, when the crankshaft throw is at the bottom of the motor, and centered between the pan rails. There is a # on each rod and rod cap, for that corresponding rod. 2 is next to 2, etc.

 

[69Bee]

The oil squirt hole is moot anymore as no bearing manufacturer supplies any bearings that have the notch. The next time you assemble a motor, you will see what I mean. The hole is blocked and is not used anymore. The only caveat to that is the early hemi bearings from Hemi Hot Heads made by King bearings (custom built for HHH, and not sold by King to the public), I noticed they had the notch.

Not all motors are numbered from the factory. Sometimes, all you get are symbols. For this reason, I number them when I disassemble the motor.

 

[Bill Monk]

The oil squirt hole is moot anymore as no bearing manufacturer supplies any bearings that have the notch. The next time you assemble a motor, you will see what I mean. The hole is blocked and is not used anymore. The only caveat to that is the early hemi bearings from Hemi Hot Heads made by King bearings (custom built for HHH, and not sold by King to the public), I noticed they had the notch.

Not all motors are numbered from the factory. Sometimes, all you get are symbols. For this reason, I number them when I disassemble the motor.

interesting. It's been a while, so not used anymore huh?

 

[miller]

interesting. It's been a while, so not used anymore huh?

Story I got on that was, the oiling holes weren't needed anymore, because of improved engine design. BS.
I added my own reliefs in my bearing set. Pretty much the only way the cylinder walls get oil!

Engine section in the SM shows how pistons/rods go into place, if that helps any.