more wc overhaul questions.

the new pistons do not have the offset built in by different length pin bosses. they both are equal length. the space between to piston bosses is wider also, so i do not have anything to gauge where i am at on centering the rod on the wrist pin for the offset, and still making sure the pin is centered in the piston.

just how much offset is there, and how do i do this to get it right?

TIA

The IT Shop Manual states on page 19, Paragraph 93: "Connecting rods in B, C, CA, and RC are offset with respect to big end bearing; rods in WC, WD, WD45 and WF are straight." Futher states: "Iron pistons for WC, WD, and WF have pin bosses of unequal length; on aluminum pistons, bosses are of equal length." The connecting rod is NOT centered in the piston or between the bosses in the aluminum pistons in a WC engine. The iron pistons have the connecting rods centered in the offset piston pin bosses resulting in the connecting rod NOT centered in the piston. If the connecting rods ARE centered in the pistons in a WC engine it will result in binding of the piston pin against the cylinder bore. If you get the engine together and to run this way it will be damaged "big time" (self destruct).

Correct, accurate, detailed procedures for assembling the connecting rods to aluminum pistons in a WC engine are given in the IT Shop Manual, page 19, paragraph 93, and shown in detail in figure AC 37 on the same page. Also note that connecting rods and pistons 1 and 3 for a WC engine are assembled one way (off center) and that connecting rods and pistons 2 and 4 for a WC engine are assembled differently (off center the opposite way).

My experience with WC and WD engines since 1973 supports and verifies the accuracy of the IT Shop Manual instructions.

Please be sure that you understand and follow the correct procedures before you assemble your WC engine.

Good luck and have fun with your WC Allis.

You could try to measure the distance on each rod down inside the piston but it is not necessary. The way I do it is to place the rod in a vice, I place the pin thru the piston and the rod, I take one hand and hold the ends of the pin so that it has as close to the same distance in from both sides of the piston. Still holding the pin in place I put a socket on the lock stud and eyeball the rod to the center of the pin and tighten the stud. That will be close enough. If you look at the rod on the left in the picture below you will see that the rod in manufactured with the proper offset.

You can click on the link and look thru the pictures if it will help.

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