Dead in the water.... Fuel?

[Knot Waiting]

My friends boat died on the river last weekend leaving me with the arduous task of towing him home, any advice to help me get his boat back under its own power would be greatly appreciated... boating alone just isnt as fun.

Its a 2003 Crown Line 18' Open with a Mercruiser 4.3MPI, Alpha 1 Gen II.

The engine suddenly died while backing down the throttle after planing out. No sputter, or stumble, just died as if someone hit the key. Would not restart. Checked the fuel, no pressure in the line therefore nothing reaching the engine. Pulled the pump and tested it on 12v seperately and it ran and pumped fine. All other systems work and the engine cranks as normal. Seems like something is interrupting power to the pump (fuses are good). Any ideas? Thanks to anyone in advance.

 

[Knot Waiting]

Re: Dead in the water.... Fuel?

Messed around with it a little bit today but still got nothing, cranks, pump runs out of the boat, but together... nadda. Anyones guess is as good as mine, so.... anyone have a guess?

 

[ghcoe]

Re: Dead in the water.... Fuel?

Pump does not run when in the boat? Check to make sure pump is getting 12 volts when hooked up to the boat wiring. If the pump is running in the boat you will need to see if it is pumping enough pressure to the injectors. Good idea to put a pressure gage in line from the pump to the injectors to see what the PSI is. I picked up a pressure gage at Harbor Freight for a few dollars similar to this one http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=95447
. Just make sure that it is rated for fuel. I got one that read from 0-120 psi. Not sure what your fuel system is rated to run for PSI, but you should be able to find out through Mercruiser. I would say you would need at least 40 PSI though. If the pump is running and you are not seeing much pressure I would check the fuel pressure regulator. Just because you have no pressure does not mean that you have no fuel flow. Hope this helps. George.

 

[searay3]

Re: Dead in the water.... Fuel?

Checked the fuel, no pressure in the line therefore nothing reaching the engine.

Check for power at the pump in the boat. There is an electrical diagram of a fuel system thanks again to DonS. Do a search. There are components such as an oil pressure switch that keeps the fuel pump running.

 

[conk3416]

Re: Dead in the water.... Fuel?

If it just suddenly died i would say its a spark issue. I would check to make sure your coil is good.