Fuel Problems. what am i looking at?
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Symtoms: Starbord motor reaches 4000 rpm and won't climb anymore. It runs great and performs exactly as is always did and is equal to port motor untill it gets to 4000 rpm. Port motor continues as always up to 5000.
So far I have checked all plug wire connections, and also pulled all plugs to see if I could see anything wrong. Also did a compression test on all 8 and they rage from 130 to 150. Is that spread ok?
next is going to be fuel filter. I hope that will be the end, however I'm looking down the raod to my next step and thinking its probably going to be a fuel pump, then I found this and took a pic in hope to get some more input.
The motor has a mechanical fuel pump, and have always noticed two fuel pump swithces on the dash, but have always assumed they serve no purpose.
This pic you are looking at is the fuel filter on the left and no idea what is on the right. what ever it is there are wires going to it (not sure if they are live, i didn't have a meter with me) As you can see the fuel line goes out from the filter into this and from this thing into the mechanical fuel pump on the motor. If I don't know that I have a mechanical pump I would guess this is a electric pump.
So far I have checked all plug wire connections, and also pulled all plugs to see if I could see anything wrong. Also did a compression test on all 8 and they rage from 130 to 150. Is that spread ok?
next is going to be fuel filter. I hope that will be the end, however I'm looking down the raod to my next step and thinking its probably going to be a fuel pump, then I found this and took a pic in hope to get some more input.
The motor has a mechanical fuel pump, and have always noticed two fuel pump swithces on the dash, but have always assumed they serve no purpose.
This pic you are looking at is the fuel filter on the left and no idea what is on the right. what ever it is there are wires going to it (not sure if they are live, i didn't have a meter with me) As you can see the fuel line goes out from the filter into this and from this thing into the mechanical fuel pump on the motor. If I don't know that I have a mechanical pump I would guess this is a electric pump.
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The pump to the right looks to be a lift pump. I have two similar pumps on my boat.
Check your fuel flow to the carb, or your losing volume. My MPIs are doing the same thing as my volume falls off the motor loses rpm. I had pluged pick up in the tank.
Check your fuel flow to the carb, or your losing volume. My MPIs are doing the same thing as my volume falls off the motor loses rpm. I had pluged pick up in the tank.