Guideplate wear, what causes this?

[Samckitt]

[Scott Parkhurst]

They're supposed to wear a little bit. It's their job.

However, when installed, they should be checked for centering. Don't snug up the fasteners until it's been centered nicely. If they're off, you can alter them (either through opening up the fastener holes or the guide openings) to get adequate clearance. Still- there will always be some amount of wear on the guide and the pushrod. If the opening is too large, the pushrod could potentially fall out from being given too much wiggle room.

[XLexusTech]

two things bad geometry, incompatible parts...

Sometimes a bad lifter will auce the push rod to **** off center as well