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Bille
08-06-2014, 11:31 AM
2003 moomba mobius lsv v-drive, 5.7 indmar engine, throttlebody injection. am looking for a wiring diagram and or any help with diagnosis. boat would turn over but not start, found no voltage at the fuel pump. this engine does not have an oil pressure relay like most have talked about under the distributor. can not find a dedicated fuse or circuit breaker either. contacted skiers choice, they say they dont have electrical diagram of engine. contacted indmar, they said to take it to a dealer to be diagnosed with their computer system.......no help there either....any other suggestions???

sivs1
08-06-2014, 11:36 AM
Do you have power every where else? When you first turn the key the fuel pumps kicks on and then the engine starts with fuel flowing. It may be an issue at the ignition by not sending power to the pump. I do not have a wiring diagram.

jstenger
08-06-2014, 11:43 AM
Check your safety lanyard. I think it is needed for the fuel pump. I had a boat that would turn over and not start without the lanyard attached.

Bille
08-06-2014, 11:54 AM
everything else works, gauges, horn, radio, engine turns over but no 12v to fuel pump. first click on the ignition key the pump will normally prime, then the beep is heard. still hear the beep but no fuel pump voltage. this boat does not have a safety lanyard either.....

jzelt
08-06-2014, 01:56 PM
This is what I have for 2004.
When our fuel pump went, it wouldn't work even directly wired to a battery.
Replaced with new pump and still no power. Replaced relays, then took it to a dealer (before wire diagram).
There is apparently a 20A fuse (marked FUEL) in line (by v-drive under the relays) that they replaced.

20628

rsinger
08-06-2014, 03:52 PM
Had the same problem on my outback a couple of years ago. Yes there is a fuse for the fuel pump, at least on mine. I don't see that it would be any different than yours. Mine was throttle body injection too.

The fuse was located at the back of the engine. There were 3 wire connectors there, one of which actually housed 3 fuses in it. If memory serves it was a mini blue fuse. If you find you have the same issue buy a few of them.

My problem was a short circuit in the low pressure fuel pump. There was also a high pressure fuel pump wired in parallel with it.

There are also relays involved, but my money's on the fuse.

Bille
08-06-2014, 06:02 PM
thanks for all the input, rsinger was on the nose, I finally found the fuse holder, looks like a test port but when you open it it had those three 15 amp fuses, one of which was blown. changed out the fuse and everything fires up!! what a difference a little 12 volts will do.......was hidden in plain site or I was just looking too hard. had my hand on that cover two or three times while tracing wires.
FYI: my setup has a metal bracket on the back of the engine which the ECM, three relays, a test port for computer diagnosis, and this fuse holder are mounted....

rsinger
08-06-2014, 09:44 PM
thanks for all the input, rsinger was on the nose, I finally found the fuse holder, looks like a test port but when you open it it had those three 15 amp fuses, one of which was blown. changed out the fuse and everything fires up!! what a difference a little 12 volts will do.......was hidden in plain site or I was just looking too hard. had my hand on that cover two or three times while tracing wires.
FYI: my setup has a metal bracket on the back of the engine which the ECM, three relays, a test port for computer diagnosis, and this fuse holder are mounted....

Forgot to mention, not to be the bearer of bad news. The first time the fuse blew, in the middle of summer, I replaced it and everything worked just fine. It blew again that fall when I was winterizing it, which is when I determined that the fuel pump had shorted out. Maybe the first time the short disappeared because I was tinkering in that area. Just something to keep an eye on.

glad I could help out.

Bille
08-06-2014, 11:19 PM
I recently did other work on the fuel system, pulled out the floor to gain access to the tank, replaced old fuel line set, blew out all the vent lines, and cleaned the anti-siphon valve which was sticking. also pulled the pump and filter assembly cleaning them and changing the filter. The boat ran fine for three or four outings then a couple of days ago dropped the boat in the water and would not start. Hopefully this takes care of it, will definitely keep some spare fuses in the glovebox.....