Ok folks I have researched this to death with the knowledge I have and what I can comprehend. I have a 2001 larson LXI 190 with a Volvo Penta 4.3 GL PEFS, the Gray Engine block models. It is equipped with a low pressure fuel pump from what I have read. Couple of weeks ago I was on the lake. Boat ran great for a couple of hours and we beached on an island for about another two hours. Started fine and backed out then forward out into deeper water. As I accelerated the boat just died. No other symptoms indicating something obvious. While I was out there floating around I checked to see if fuel was getting into the carb when I pumped the throttle. I beleive I did see it when I had my wife do that for me, but now Im not sure because it would not start since. Towed back to campground and I started checking things. Boat would turn over fine. While in the campground with the boat on the muffs I checked to see if the carb was getting fuel. It was not. Pulled fuel filter. Seemed to only be 3/4 full. dumped it put it back on. did not fill it back up. turned it over again. No start so I pulled filter but no fuel getting into the filter. Starter fluid sprayed into the carb I was bale to get it to fire a little. Checked several plugs grounding on the block to see if I had spark. All good. plugs looked decent. I assumed it was just the pump. Started researching and now I am very concerned and confused. I just pulled the pump and tested straight off the battery. When energized it works, or at least kicks on as if it is pumping. Didnt do that for long as the pump is empty and dry. I found the schematic from another post of the wiring and there was mention of two diodes. Seemed this has been hashed out before but not sure if it is whatmy problem is. Iv'e seen some report of fixes with same symptoms but it be something different. I have started taking the insulation tape off the harness to find these diodes. Have not found them yet. Checked 7.5 amp fuse. continuity check shows its good. the really looks different to me. Its essentially a relay block that is not labeled though the schematic is labeled so i see what wire does what. the schematic shows the wires from the alternator but the one that should be green is not green which is supposed to have a diode in line to the pump or the relay. It doesn't look as if it has been altered from factory though. Also this relay block just has the wire hooked to the connectors but there is no normal looking relay plugged into this block. Is there supposed to be one? I've never had one on there and the boat always started fine and ran great.
So I am at a loss at the moment trying to trouble shoot before I take it to a mechanic. I'd like to go in somewhat educated and be able to tell everything I have trouble shooted so they can focus on the problem and not chase supposed gremlins. From what I have read from the forums and what I can find, this set up uses the starter when cranking to energize the pump. Once started and key goes back to on position the alternator takes over energizing the pump from the green wire with a diode in line. There is another diode somewhere on one of the wires also coming from the relay block, from what the schematic shows. these diodes are in place so that power does not backflow through the wire somehow. If that is all correct in layman's terms are these diodes a problem? have any of you dealt with this, replace them, test them, and how far down the line in the harness are they?
I know this is a long story but wanted to get as much info to you all that I suspect would have been asked of me. I am going to pull the floor panel and check the fuel hose from the tank. I guess there is a fuel pick-up and screen i need to check? is there another pump in the tank? I assume yes or does the electric pump I mention suck the fuel all the way from the tank.
Thanks if you can shed some light on this.
Conrad
So I am at a loss at the moment trying to trouble shoot before I take it to a mechanic. I'd like to go in somewhat educated and be able to tell everything I have trouble shooted so they can focus on the problem and not chase supposed gremlins. From what I have read from the forums and what I can find, this set up uses the starter when cranking to energize the pump. Once started and key goes back to on position the alternator takes over energizing the pump from the green wire with a diode in line. There is another diode somewhere on one of the wires also coming from the relay block, from what the schematic shows. these diodes are in place so that power does not backflow through the wire somehow. If that is all correct in layman's terms are these diodes a problem? have any of you dealt with this, replace them, test them, and how far down the line in the harness are they?
I know this is a long story but wanted to get as much info to you all that I suspect would have been asked of me. I am going to pull the floor panel and check the fuel hose from the tank. I guess there is a fuel pick-up and screen i need to check? is there another pump in the tank? I assume yes or does the electric pump I mention suck the fuel all the way from the tank.
Thanks if you can shed some light on this.
Conrad
