The fuel pump noise, with convincing video

[ke70dave]

ok fellas im almost at my whits end with this.

the setup:600ml surge tank, mounted under car. faccet external lift pump. BRAND NEW bosch 044 external pump. standard fuel lines.

(ps i know the bosch 044 is complete overkill for a 4age, but i got it from a mate )

here it is

http://www.ae86drivingclub.com.au/dcimages/2/0/2/17818.jpg

ok the problem.

THE NOISE!!!!!!!!!!!ARRRRGGGGGGG i cant take it anymore. i literally get frustrated with this noise, to the point where i have to get out of the car! like nails on a chalkboard.

heres a vid.

http://www.youtube.com/watch?v=D-ck-OSfxg8

as you can see/hear in that video that annoying noise is driving me nuts. it doesnt do it all the time. at first startup its sometimes silent. and sometimes it stays silent for a long time. it tends to make that noise after a drive longer than ~15mins.

now i know that alot of you are saying "fuel pumps are noisy put up with it". but the whole idea of this surge tank setup is so to be quiet and not surge, since the pump should be supplied with good fuel 100% of the time. and the fact that it is silent sometimes means that it shoudl be possble. and also the fact that an almost exact setup is in my mates 86 and its silent.

ok so anyone got any ideas? or had this before?

[pen15]

just get a smaller quieter pump omg866's car sounds like a jack hammer ill just say put up with it lol

[fantapants]

sounds like you might have something caught in the pump impeller section?

might pay to pull it all apart and a real careful flush and clean out?

do you run pre pump filters befor the lift pump AND befor the 044?

[ke70dave]

sounds like you might have something caught in the pump impeller section?

might pay to pull it all apart and a real careful flush and clean out?

do you run pre pump filters befor the lift pump AND befor the 044?

the only filter i have is a filter just before the fuel rail.

admittedly i prolly should have a filter before the pumps. but i didnt think it was too necessary.

also ive been discussing with a mate, he tends to think it might be voltage drop and its not getting enough power down there. ive only got 1 wire powering both the pumps (fairly chunky 2.5mm^2) but might not be enough.

[reecegze]

I wouldnt of wired it that way in my opinion. You should run your main pump off the COR relay and run the lift pump from the battery to a relay, and use the main pump to switch power to the lift pump. That way you can fuse both pumps and check if they are drawing enough amps

[FAST EDDIE]

generaly they are noisy as fk man, extra carpet in the boot area to muffle noise?? oh i had one of those carby fuel pumps and replaced it with a new one which was alot noisier than the origional old one i had!!

[fantapants]

pumps are funky things man, and there is often a lot of crap floating around in tanks. allways assumed it was common to put pre pump filters in... :)

[DR86FT]

try thicker rubber for mounting it ... might make it a bit quieter

[Oly AE86]

I am not alone!!! it is THE most horrible noise. :s

I have the same noise SOMETIMES with both my old Bosch 070 and current Bosch 910. It will happen randomly, sometimes when I been driving with spirit and things are hot, but not always.

I believe it is a form of cavitation/starvation because I can feel it through the floor near the pedals, and feeling the pump it is not happy. I have a similar setup to you, I have a Goss lift pump with an inline filter before it, then a smallish surge tank then the main pump. I replaced the lifter pump once before, thinking it was the cause, but to no avail.

It is quiet at the moment and so I am content. I don't believe it is a low voltage problem, but next time I can I will check it out.

[ke70dave]

thanks for the replys guys.

and yes oly you arent allone. i drove to church tonight, and around a bit dropping some guys home.

it was really noisy at first, then it got worse....then the last 10mins it was silent.....

thinking about mounting the pump a bit lower than the tank, so there is more "Gravity" happening. or maybe even turning the pump on its end
so it cant possibly cavitate...

wonder how a bosch pump feels like pumping "up"....

[Jdm070]

as you can see/hear in that video that annoying noise is driving me nuts. it doesn't do it all the time.

Your setup sounds exactly like what mine did in my old ke70 sedan. And, it would be sometimes loud, sometimes quiet.. gave me the shits too!

I only ran an external bosch VL pump with one fuel filter near the rail. (no lift pump or surge tank)
Here's a pic: http://www.ae86drivingclub.com.au/dcimages/2/7/2/1/25414.jpg

I was thinking maybe it was the size of the fuel lines making the pump strain.. or maybe it needed a filter in front of the pump..? i cant remember if i swapped the 4mm factory return line and made it the tank breather or if i changed it to 6mm feed, 6mm return and 4mm vent/breather. was awhile ago now.

But Im about to do an efi 4A swap in my van and i don't want to make the mistake again! hopefully you can figure out what is causing your setup to be so loud so i don't have the problem too. :)

[Hen may possibly be a nut]

Might be one of those hard to track down problems, but a few things I'd try are:
- Put a filter between your tank and lift pump.
- Check voltage at the pumps while running, and if it is much below battery voltage, run bigger wires (all the way from the battery, and through your relays).
- Drop your EFI pump a bit, so it sits level with the surge tank outlet
- Rubber mount the pumps better. On a holley blue, I used two 10mm thick layers of rubber, and the thing is still annoyingly loud.

And if all that fails, just turn up the stereo.

Hen

[ke70dave]

Might be one of those hard to track down problems, but a few things I'd try are:
- Put a filter between your tank and lift pump.
- Check voltage at the pumps while running, and if it is much below battery voltage, run bigger wires (all the way from the battery, and through your relays).
- Drop your EFI pump a bit, so it sits level with the surge tank outlet
- Rubber mount the pumps better. On a holley blue, I used two 10mm thick layers of rubber, and the thing is still annoyingly loud.

And if all that fails, just turn up the stereo.

Hen

ah cheers for that, yer those things are on the list of things to do. ill check the voltage this arvo when i get home. i was thinking last night of extending the pipe from the surge tank to the efi pump, currently its only about 100mm long, which i thought would be good, but maybe its causing some turbulence or something..ive got a spare piece here ill chuck it in and see how it goes. then the "surge tank" is slightly higher volume as well, so might improve things.

you might be right about the stereo thing...i also don't want to destroy my pump.

[Hen may possibly be a nut]

The length of hose shouldn't be an issue. I ran a VL pump out of probably exactly the same surge tank, and used about 60mm of hose. It didn't give any problem.

Hen

[Juturna]

my 044 does that when its on an angle like up a really steep hill when i have low fuel level in the tank. id say its air in the pump, but yea definatly put a filter before each pump, if one spits an impellor you dont want 2 screwed pumps.