As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKE-OFF INITIAL CLIMB GEAR HANDLE GEAR WOULD NOT RETRACT. TROUBLESHOT & FOUND NOSE STRUT NOT PROPERLY EXTENDED DUE TO LEAKING LOWER NOSE STRUT SERVICE VALVE. REPLACED LOWER NOSE STRUT SERVICE VALVE WITH A NEW VALVE & SERVICED NOSE STRUT PER MM 12-10-78. VERIFIED PROPER OPERATION OF LANDING HEAR HANDLE IN AIR MODEL PER MM 32-30-00.