No power at fuel pump

[aparisi59]

took the boat out of storage. won't start no power at fuel pump. jumped the pump. it works. so where does the power come from. trying to fix this issue. there is a relay next to the pump. swapped with the other motor and had no luck. does the power come from the relay on the starter? volvo penta 3.4 gl

 

[aparisi59]

i did get the engine running but the pump stops pumping after i remove the jumper. i believe the alt takes over after she starts

 

[alldodge]

A bit hard to follow but the power to the relay comes from the battery thru a fuse. Check the fuse first and what GL model do you have it goes A thru E

 

[aparisi59]

unsure which model i have. it is a 2000

 

[alldodge]

Need a voltmeter to see were power is and what level.
When you lump the fuel pump are you going straight to the battery power? If so check the fuse

Here is a C-D model (V8 but V6 would be same) but unsure which is a 2000

 

[aparisi59]

mines the 4.3. i accidentally wrote 3.4

 

[aparisi59]

judging by this pic that you provided. power comes from the starter solenoid . goes to a 50 amp breaker, goes to a fusible link and then to the relay which does the rest. now i gotta find this pic for my boat. i can't remember engine code

 

[aparisi59]

4.3l GL PEFG so that means a G correct?

 

[alldodge]

Yes, I figured it was a 4.3
Where were you jumping the fuel pump to keep it running?
Did you check the fuse?

 

[Bt Doctur]

AD, main pump power comes from the alt thru a diode (green color). power for the pump during cranking comes from the diode in the start circuit. (yellow to orange)
Best option is to install a oil pressure switch and a dedicated power circuit.

 

[Bt Doctur]

30 connects to 87 for main pump power,pin 86 is energized with the key on "start" using a blocking diode and once started the alt provides the power to keep the relay closed using another blocking diode 30 to 87.
Leave it to Volvo to engineer such a complex setup ,lost the alt and lose your fuel pump and go dead in the water.

 

[Scott Danforth]

the volvo is already set up with an oil pressure switch, power from the diode, bypass circuit from the starter solenoid.

if its not running without being jumped, either the diode from the alternator is dead, or there is no oil pressure.

 

[alldodge]

BT I understand how it works, just starting from another angle try to figure it out

 

[aparisi59]

Ok so I'm at the boat now. The fuse was blown changed it it blew as soon as I turn it over. I see power at the fuse. But it gets weird at the relay. Jumped it from the battery directly with a speaker wire and the wire gets hot fast. Took pump out to see what happens on the bench. Runs fine on the bench.

 

[aparisi59]

Looks like I have 12v on the peach colored wires

 

[alldodge]

There is a possibility that the relay is shorted internally. To see if this is the case, reinstall pump and replace the fuse.

Remove the relay, then jump across contacts between the red/Purple (30) and Yellow/Red (87) contacts. If fuse blows, then your pump needs replaced, if it runs fine then need another relay

Also assuming your talking about the 7.5 amp fuel pump fuse

 

[aparisi59]

Trying to upload a pic. But I think my phones camera is to good

 

[aparisi59]

I wonder if it's a ground issue how come on the bench it's fine but in the boat the wires getting hot and blowing a fuse when I turn it over

 

[aparisi59]

My wife isn't green

 

[aparisi59]

I dont hear pump with key on either