1994 V6 Johnson 150 HP 60 degree...Have had idling, low rpm backfire (lean), woes since purchasing this "re-built" engine. Have rebuilt all carbs, new spaghettis on both throttle bodies, compression good, inspected pulse limiter (blue type)
engine idles like sh*&^*&, but when up to about 1800 rpm or so, kicks in and runs like it should..no high end rpm woes....except very poor fuel economy..may be the nature of the beast...
Have also rebuilt air-motor and fuel diaphragm (and assoc. washers etc.) on the VRO. VRO is capped and disconnected, pre-mix fuel supply. I also swapped a capped VRO pump off an older 140 and same symptoms below repeat.
Further trouble shooting, today, put clear 5/16 hose at: a) barb on fuel supply line at in-line filter...b) both sides of carb intake tubes.
here's what is going on:
fuel in appears to be bubble free..ie. no air-leak from the tank to the in-line filter barb...
while idling (w/ flusher), w/ tight bulb, pump clicks about every 10 sec or so as expected; however, as fuel continues to flow 30-60 sec or so, pump begins to click more and more rapidly, as well as erratically, when I pump primer bulb tight, it calms back down....now, also noticed that as pump begins erratic click, AIR very obvious in both lines between carb intake tubes and VRO assy. outputs.
I believe that the air-motor shaft seal in the intermediate housing must be bad and allowing crank gases to pass to the fuel diaphragm side....although visual inspection doesn't reveal any obvious defects....
the in-line filter doesn't appear to be leaking, and the o-ring seals at the fuel out let on the bottom of the vapor separator and the o-ring seals at the fuel pump outlet appear to be OK...
Any knowledgeable OMC guru's out there that have seen this symptom??? PLEASE HELP ME>>>...I'm ready to go fishin and quit wrenchin...
engine idles like sh*&^*&, but when up to about 1800 rpm or so, kicks in and runs like it should..no high end rpm woes....except very poor fuel economy..may be the nature of the beast...
Have also rebuilt air-motor and fuel diaphragm (and assoc. washers etc.) on the VRO. VRO is capped and disconnected, pre-mix fuel supply. I also swapped a capped VRO pump off an older 140 and same symptoms below repeat.
Further trouble shooting, today, put clear 5/16 hose at: a) barb on fuel supply line at in-line filter...b) both sides of carb intake tubes.
here's what is going on:
fuel in appears to be bubble free..ie. no air-leak from the tank to the in-line filter barb...
while idling (w/ flusher), w/ tight bulb, pump clicks about every 10 sec or so as expected; however, as fuel continues to flow 30-60 sec or so, pump begins to click more and more rapidly, as well as erratically, when I pump primer bulb tight, it calms back down....now, also noticed that as pump begins erratic click, AIR very obvious in both lines between carb intake tubes and VRO assy. outputs.
I believe that the air-motor shaft seal in the intermediate housing must be bad and allowing crank gases to pass to the fuel diaphragm side....although visual inspection doesn't reveal any obvious defects....
the in-line filter doesn't appear to be leaking, and the o-ring seals at the fuel out let on the bottom of the vapor separator and the o-ring seals at the fuel pump outlet appear to be OK...
Any knowledgeable OMC guru's out there that have seen this symptom??? PLEASE HELP ME>>>...I'm ready to go fishin and quit wrenchin...