Mercury Mariner 200, 225 Optimax Outboards Service Manual, 90-855348, Page 134Get this manual
3With retainer installed in pump body, break retainer rod from retainer by bending sideways 5Place boost spring into pump body and place cap onto boost spring"23601
aRodRetainer Cap
4Reinstall rod into retainer cap and, use small hammer or hammer and punch to tap rod down into retainer until flush with top of retainer
aBoost SpringPump BodyCap