The 658088 is an intake hydraulic lifter (tappet) used in Continental aircraft piston engines. It is part of the valve train system and is responsible for maintaining zero valve lash while transmitting camshaft motion to the intake valve mechanism.

Key features include:

OEM Continental hydraulic lifter (intake side)
Self-adjusting hydraulic mechanism to eliminate valve clearance
Precision-machined steel body with internal hydraulic plunger system
Maintains constant contact between camshaft and valve train
Designed for continuous-duty aircraft engine operation
Lubricated via engine oil pressure system
Reduces valve train noise and wear compared to solid lifters
Used in Continental IO/TSIO engine families (application-specific)
FAA-certified engine valve train component