Volvo Power Problems... Bad Fuel Pump?

dvallish1

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I have twin (2008) 8.1Ltr Volvo Penta Engines that were recently serviced with new plugs, fuel water separators etc. On my second full tank of gas I experienced low power with WOT on port side, and the starboard side would rev up to 3KRPMs and then idle back down to idle rpms I changed the fuel filters, and was able to squeeze out a bit more rpms on port but not starboard. What could cause the rpms to go up and then down? What could be the problem a bad and weakening fuel pump?
 

Bondo

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Re: Volvo Power Problems... Bad Fuel Pump?

I have twin (2008) 8.1Ltr Volvo Penta Engines that were recently serviced with new plugs, fuel water separators etc. On my second full tank of gas I experienced low power with WOT on port side, and the starboard side would rev up to 3KRPMs and then idle back down to idle rpms I changed the fuel filters, and was able to squeeze out a bit more rpms on port but not starboard. What could cause the rpms to go up and then down? What could be the problem a bad and weakening fuel pump?

Ayuh,..... Welcome Aboard,.... Is anybody inspectin' the Contents of the take-off filters to see what's in 'em,..??

That's a rather Important diagnostic tool,...

Is this an Efi/ Mpi motor,..??
 

jerryjerry05

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Re: Volvo Power Problems... Bad Fuel Pump?

pump1.jpg


Need the model #s and any info on the motors?
The BB's have a high pressure pump.
There is a schrader valve on the injector rail.
Test the fuel pump pressure.

Like Bondo said crud in the filter can stop you.
Look in there?
The pic might look like your setup.
The tube on the right(#8) is the HP pump.
 

dvallish1

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Re: Volvo Power Problems... Bad Fuel Pump?

Ayuh,..... Welcome Aboard,.... Is anybody inspectin' the Contents of the take-off filters to see what's in 'em,..??

That's a rather Important diagnostic tool,...

Is this an Efi/ Mpi motor,..??

Yes Ef motor.. what is a "Take-off Filters"?
 

Fun Times

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Re: Volvo Power Problems... Bad Fuel Pump?

what is a "Take-off Filters"?
That is New York talk:D for when you removed the old fuel filters, did you dump the old remaining fuel into a clear container to check for things such as water or debris.

So essentially both engines are down on power while under load? One thing to take into account would be if both engines share the same fuel port fitting (anti siphon valve) coming out of the fuel tank or does each engine utilize their own fuel port fitting.

Since your engine model is an MPI, while it's down on power, is there any warning horns associated with the lack the of power?

A fuel pressure check is going to be essential.
 
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