Pic. 6.21 a. Timing chain straightening is measured by checking the length of the chain section and 8 links (16 roller axes) but three or more places not the entire length of the chain
Pic. 6.21b. Wrap the chain around each of the sprockets and measure the diameter of the sprocket on the chain rollers. If the measurement is less than the minimum sprocket diameter, the chain and sprockets must be replaced
22. Check guides for excessive wear (pic. 6.22). Replace the chain guides if the wear exceeds the limits given in the Specifications at the beginning of this chapter. Keep in mind that some scratches on the timing chain guide are normal. If excessive wear is observed, the chain guide oil hole on the front of the cylinder block will also need to be inspected for blockage (rice. 14.5). The oil pump is driven by a second chain driven by a sprocket on the crankshaft. If the target timing mechanism needs to be replaced, replace the oil pump drive chain at the same time (see paragraph 14).
Pic. 6.22. Timing chain guide pump measured from the top of the chain contact surface to the bottom of the wear grooves