Fuel pump whining/engine power loss problem not solved with new two stage Volvo pump

[dennismo]

The engine would lose power intermitently (and still work at low speeds but not 2000 rpm and above) and at the same time as power loss, the two stage fuel pump got very noisey. When the pump noise went away, the power returned. The same is happening with the new pump I installed. I checked the salt water cooling of the pump through the small hoses by blowing in each of the hoses, and I could blow which I think means they are clear.

Would anyone have any suggestions?

Very gratefully yours,

Dennis

 

[dypcdiver]

Sounds as if something is restricting the flow of fuel. Things to check, tank pick up might just have a clogged filter, there might be a pinch in the supply hose or piping. fuel filter might be clogged or have too much water in it.
It would be a good idea to get the fuel pressures checked too.
You don't say what engine you are talking about, might just be helpful if you let us know.

 

[dennismo]

Thanks for your reply. It is a 4.3 GXI.
I have not checked the fuel pressures but will as the next step. I think it is obvious they will be down!

 

[NoExcuses]

Check the screen on your fuel pressure regulator.

 

[dennismo]

Thanks. Is it the device that controls the flow back to the pump after the fuel arrives at the rail??

 

[tkrfxr]

Also check the electrical connectors to the fuel pumps....I had a similar experience and found the electrical connector to the high pressure fuel pump had come loose from the vibrating hoses next to it... whenever I tried to get the boat on plane, it would fail to hold rpms and would not go above 2000....


good luck.

 

[Dave-R]

I think it sounds like the suction is partially plugged on either on of the pumps. Quite a few people here have disassembled their pumps and cleaned the screens.
First and easiest would be like dypcdiver said and check the tank mounted anti syphon check vale first. Dave-R

 

[Daleg70]

As someone previously -- check those electrical connections at the pump --- it you can jiggle them and hear a change you might have found that answer.

 

[NoExcuses]

Thanks. Is it the device that controls the flow back to the pump after the fuel arrives at the rail??

I don't know the exacting routing of fuel throught the fuel rail. The fuel pressure regulator is item 23 in the link.

http://www.volvopentastore.com/Fuel...on_id.396492410--store_id.366--view_id.775644

 

[NoExcuses]

There is also a service bulletin that says to replace the screen with an e-clip. I can't seem to paste the link here but you Google Volvo Penta Bulletin P-23-7 it be the first hit.