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Pistons on the left (passenger side) are 1-2-3-4.

You need to install them in the correct order.


I'm putting my W back together. Put the crank on and turned just fine. Aren't the pistons/rods supposed to fit in the left/passenger side as 1-3-5-7, with the right/driver side as 2-4-6-8?

Everything was going just fine with pistons/rods 1-4, all pointing towards the front of the engine. I get to piston/rod 5, and all of a sudden the number on the cod/cap was no longer showing on the passenger side of the rod, as was the case with rods 1-4. Did the machine shop screw up, or me?

With piston/rod 6, I couldn't seat the rod on the crank - oh the pain... Nothing I tried made it fit.

I also noticed that one side of the rod/cap was flat, whereas the other side had an angle grind. Aren't the flat sides supposed to be toward the other rod/cap, with the angle grind toward the crank side? I'll also post a few pics later, after I self-diffuse.

Frustrated as hell in Slinger. Eric.
 

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Your thinking is correct, the notched side goes against the crank. Did the machine shop press a few pistons on backwards?
 

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Passenger side front to rear 1234 drivers side front to rear 5678. Sometimes the pistons have notches to that are supposed to face the front of the block.
 

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Discussion Starter #5
After heading to the local gas station for some brainwave improving beverages, imbibing a few, and finding my large block engine book, realized the left was supposed to be 1-2-3-4. Never would have thought there would have been a difference, but certainly 3-7 combo worked, whereas 5-6 rods on the third crank journal were too wide. I'll be ordering that small block engine book...
 
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