{"nhtsa_id":600548,"type":"service_bulletin","type_name":"Service bulletin","date_added":"1998-05-20","date":"1998-03-24","document_id":"107","mfr_campaign":null,"replaces":null,"component":"ENGINE AND ENGINE COOLING:ENGINE","mfr_system":null,"summary":"IDENTIFYING ALL FIELD SERVICE UNITS USING THE 031-3305 PILOT OPERATED CHECK VALVE THAT HAS AN INCORRECT VALVE SPRING IN THE VALVE ASSEMBLY. *YC","document":null,"url":"https://open.wenmarpro.com/bulletins/600548","components":[{"id":"engine","name":"Engine","parent":null}],"codes":[],"topics":[],"vehicles":[{"make":"HEIL","model":"HEIL","year_from":null,"year_to":null,"match":null,"vehicle_ids":[]}],"as_of":"2026-10-19","note":"A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.","attribution":[]}