Help - is my headgasket going....??

[nick]

Originally Posted by ngoma

Easy. Gasket is a large thin oval-shaped o-ring. Loosen the lower nut first when disassembling, tighten it first when assembling, to avoid breaking the lower boss. Take care to not let the actuator rod slide all the way out. If it does slide out, you must replace it in the same orientation.

I've pulled my vacuum pump numerous times in order to mess with the IP timing and injectors. I've never noticed anything that would lead me to believe orientation mattered. It seems that it rotates about its axis, since every time I pull it out it is in a different location about its axis. I realize that the push rod has a flat "side" to it, but I thought that was just for lubrication purposes. Would you mind sharing with me how the orientation of the push rod matters?