1985 OMC 65, 100 and 155 HP Models Commercial Service Manual, PN 507450-D, Page 105Get this manual
Fuel Tank Fuel Mixture matar in excellent mechanical and aperating canditian, may give faulty perfarmance because af an improper fuel mixturePetraleum gum and varnish which precipitate fram stale mixture, may clag the filter screen and any small arifices, interfering with starting and narmal runningThe use af OMC 2+4 Fuel Canditianer prevents and remaves gum and varnish depasitsFar praper fuel mixtures see Sectian Engine Fuel and LubricantToassure that the fuel tank cantains the praper mixture, drain and flush the tank at least ance year, and at every tune-up ar majar repair at an autdaar lacatian, away from all possible sources of ignitionTofacilitate camplete draining af the tank, drain screw is pravided in the fuel tank upper hausingClean the tank by flushing with clear gasaline or salventPrimer pump, screens, etc may be inspected and cleaned as described belawRefill the tank with the carrect fuel mixture
Cleaning, Inspection and Repair
If the tank ar hase appears tobe leaking fuel ar fumes, pressure test tank and hase assembly befare daing any disassemblySee Testing After RepairClean the fuel tank and inspect far rust ar leakageReplace tank if badly rusted ar if it has develaped leaks in the metal bodyNever apply patching materials toan outbaard fuel tank even thaugh these materials are said as being suitable far fuel tank repairGenerally, these materials are said far repairing autamative fuel tanks and are nat suitable far partable marine tanks which are subjected tomuch higher pressure and vacuum can ditionsUsing fuel tank which has been patched could result in fuel leakageIgnition of this leakage could result in fire or explosion