Mercury Mariner V-250 V-275 Outboard Service Shop Manual 1990, Page 324Get this manual
Oil Injection Components (See Page for Location) (D Remote 011 Tank Holds gallons of oilThe tank is pressured by air rom crankcase pressure thus forci ng oil up he outlet hose to he oi reservoir engine
CD PSI Check Valve
At id le he pum will meter the oil at approximately 80 to gaso line to oil ratio and at W.O.T 50 to ra tio
0 011 Pick Up Tube 011 Reservlor
If oil low to reservoi is obstructed and injection pump continues to pump oitthe PS valve will open to allow air to enter reservoir to prevent vacuum Check Valve