The chain and front output shaft with sprocket go into the case together. Some slight adjustment of the output shafts and a careful fitting of the chain makes installation possible. Without the rear case half installed, there is slack in the chain. This is normal. (If you suspect chain wear, compare chain length with a new one.) Fit the front output shaft into its bearing. Do not force these parts together. Installing the yoke will seat the shaft against the bearing collar. Aligning the outer end of the output shaft will remove chain slack.