View Single Post
  #20   IP: 68.111.11.84
Old 03-02-2015, 01:45 AM
JOHN COOKSON JOHN COOKSON is offline
Afourian MVP, Professor Emeritus
 
Join Date: Nov 2008
Posts: 3,500
Thanks: 54
Thanked 855 Times in 629 Posts
Rod
The electric fuel pump should not operate unless the key is in the on position and the engine is running and the oil pressure is up. This is accomplished by a pressure sensitive switch that closes when the oil pressure is up. This switch is referred to as the "oil pressure safety switch" or OPSS. On your boat is there a lead that goes from the electric fuel pump to a terminal on the OPSS? The typical wiring sceme is coil + to the OPSS then from the OPSS to the fuel pump. Is your OPSS missing, shorted across, or bypassed? My guess is that someone wired from the key directly to the fuel pump and bypassed the OPSS. The OPSS is required by Coast Guard regs.

TRUE GRIT
Reply With Quote