Winnipesaukee Forum - View Single Post - Gas-Mechanical problem with boat engine

TomC · 05-30-2008, 08:35 AM

of this with his statement that the engines won't draw fuel.. Because of the balance shaft, which is necessary on the V6 even though it is basically a sawed-off V8, the fuel pump is not mechanically driven by the camshaft. Instead the V6 engines have an electric fuel pump which do fail from time to time. Unfortunately, this is an expensive part ($200).

there are some other twists to this too.. the power to the fuel pump is tied to the oil pressure switch to cut off fuel in the event of loss of oil pressure...

So you may ask: How does the engine ever start then (before oil pressure is developed)? Well, the fuel pump is energized by a separate circuit during engine start/crank..

So, Bigdog, besides all the other stuff that you are going to do/check - you might want to be sure that your fuel pump is properly powered and working.

I had a 1997 4.3L V6 that had a "soft" failure of the fuel pump - it wouldn't develop full pressure and it took awhile to fill the carburetor bowl.

05-30-2008, 08:35 AM	#18
TomC Senior Member Join Date: Apr 2004 Location: Lakes Region Posts: 819 Thanks: 42 Thanked 185 Times in 116 Posts	Dave reminded me.. of this with his statement that the engines won't draw fuel.. Because of the balance shaft, which is necessary on the V6 even though it is basically a sawed-off V8, the fuel pump is not mechanically driven by the camshaft. Instead the V6 engines have an electric fuel pump which do fail from time to time. Unfortunately, this is an expensive part ($200). there are some other twists to this too.. the power to the fuel pump is tied to the oil pressure switch to cut off fuel in the event of loss of oil pressure... So you may ask: How does the engine ever start then (before oil pressure is developed)? Well, the fuel pump is energized by a separate circuit during engine start/crank.. So, Bigdog, besides all the other stuff that you are going to do/check - you might want to be sure that your fuel pump is properly powered and working. I had a 1997 4.3L V6 that had a "soft" failure of the fuel pump - it wouldn't develop full pressure and it took awhile to fill the carburetor bowl. Last edited by TomC; 05-30-2008 at 05:09 PM.