The fake shell H 51302 is a precision-machined auxiliary component used in the Sulzer ASL25 engine for assembly, alignment, or testing purposes within bearing or housing arrangements. Designed to replicate the geometry and fit of an operational shell without performing a load-bearing function, it allows accurate setup, measurement, and verification during maintenance or overhaul procedures. Manufactured to tight dimensional tolerances, this fake shell supports safe handling of critical components, reduces the risk of damage during installation, and contributes to efficient, repeatable service work on the engine.