Fuel pump and battery

[bigg_vin]

Hey peoples,

i have 2 problems which may be related hence the one thread.....

firstly, my holley blue fuel pump sometime is really loud and sometime is not..... most of the time, it is.
By loud, i mean it can be heard over my ehaust system, inside and outside the car. as far as i have noticed, it goes from loud to soft when ever it feels like it, and not when i touch anything specific in the car.

secondly, my battery, or alternator, i think, if wrecked....
i need to push start my car cos the battery is always so dead..... even if i have had the car running for a while, then switch it off, and try start it straight away, it is completely dead. the voltage at the abttery reads 11V when nothing is on, 7V when trying to crank, and 13V when charging.....

if anyone can help my two problems, i would be very apreciative!

cheers

 

[SL/ENUT]

Thats the problem with Holley blue fuel pumps, they all do it!. Perhaps put some rubber around it and it might make it quiet.
The battery problem, i reckon its the alternator, these can take all the power out of a battery if its stuffed. The problem could be worn brushes, or diode inside cactus.

 

[vk3800]

I'd say battery, as its giving a higher reading when charging. That is if by charging you mean the car is running and not on a battery charger.

 

[craigvk]

The fuel pump sounds like it's breaking down. Maybe get a rebuild kit for it. I know you can for standard Holden fuel pumps.

As for the battery/alternator problem. Speaking from experience... Disconnect the lead from the alternator to the battery at the battery. Run the car and check the voltage at the alternator lead. It must measure 14-14.4 volts. Anything up to say about 15 volt is ok. Anything less than 13.5 volts there is something wrong with your alternator. The brushes would likely need replacing. The battery electrolite should be checked to make sure the fluid is full. If it isn't, top it up and put it on an automatic charger. Might take almost a day to charge, but the battery sounds a bit crap i.e. dead.

Check all the leads in the engine bay. Earth, starter and alternator plus your existing positive loom. If any look dodgy like having electrical tape wound on them or frayed wiring, GET RID OF IT! Replace it with new wiring. Use good battery lugs, solder and heatshrink. Avoid electrical tape.

 

[bigg_vin]

thanks for the help people.

ive done a little more investigating, and have found that when im in accessories/start, the battery voltage is fine, still at 11.3V, but as soon as i try and crank, the voltage drops to 3V......

ive checked the wiring, and it seems fine.....

does anyone know what could cause this?
cheers

 

[Goon]

What accessorys do u have added on?

What brand of battery? heavy duty? etc..

I've heard batterys like century only last 6 months...

 

[bigg_vin]

its literally a brand new battery, a heavy duty, 550CCA, exide brand battery...

is it possible it is the starter motor? ive heard in some cases that when the started sh$ts itself, it draws a way too high current when cranking?

cheers

 

[Goon]

The alternator is what charges your battery.

Do u have any additonal 12v items that turn on while u start her? they could be draining power..

To test the starter motor, take her outand grab another battery, connect the postive to the right place eg.. where the postive lead normaly go's .. then rub the negative on the side of the starter motor and see how it spins.

Are your battery leads new? i replaced my 20+yr old Negative battery lead with a new one and got a way better connection.

sometimes u can be surprised and find that the battery was faulty to begin with.. even though its new

 

[mercury2006a]

ok your battery voltage when charging (easiest way to tell is get a multi meter from dick smiths for like $14 and put it on the battery but so you can see it when you crank and start the car rev it to about 1500 ish and hold it there then see what the voltage is.
per all of the electrical stuff in my VK ive done the VN alt conversion on mine i can supply some pics and info if ya want so anyway i now run an 85amp alt

so yeah the output voltage when charging (checking with a multi meter at the battery) should be close to 14.4v if its not then i would be surprised if your alt isnt on its way out.

 

[bigg_vin]

ive checked the voltage when charging, its 13.6V.....

which is low, but would still be charging the battery....

cheers