When heating aluminum timing gears prior to press fitting on camshafts, caution should be exercised that the gears are not heated above 200 degrees F.
When timing gears are subjected to extreme temperatures, the aluminum gears do not return to their original dimensions after cooling. The result is a loose fit between the gears and camshaft. Under no circumstances should aluminum gears be heated with a torch.
Casting numbers in the skirt or body of the piston may not represent the actual part number of which the casting has been machined.
Depending on the manufacturer, one piston casting could be used for more than one final part number.
Example: 1073565 casting being machined into a 1073565 (piston with one valve relief) or into a 1654262 (piston with two valve reliefs)
Examples of another manufacturer’s casting numbers recorded that are also active part numbers are:
• 7E7600 (3400 series)
• 1073565 (3300 series)
Piston part numbers MUST be taken from the crown of the piston where the part number is usually stamped, etched or inked and NOT from the skirt or bottom of the piston body where it may be cast in.