Noisy M400 Fuel Pump!

[Fett]

Well I fitted my Bosch 979 pump the other day and low and behold it's noisy. It's making a cross between a rattle(like a nut rolling around in a washing machine)/ bubbling noise. It seems to be coming not from the pump itself but the outlet pipe that runs to the fuel rail.

I expected a bit more of a thrum or buzzing noise but not this. So was wondering if anybody can tell me if it's normal or have I messed something up?

My old 910 pump was completely silent unless it got very hot, but even then it never made a noise like this.

I checked all the pipes etc to make sure there ok and there is no vacuum building in the tank. Have also had the wiring mod done.

Only had a chance to take it for a quick spin the other day but it drove fine, felt better than normal really, although I didn't give it any real welly because of the noise.

Had a search and could't find anything on the M400 pump being noisy which is why I went for it instead of the 044.

Anybody help?

[Rob_W]

Not much of a consolation but my M400 pump(s I've tried two, one at a time to be clear) have both been noisy and I think it only really started after the wiring mod i.e. when it/they was/were working properly! I've done loads of things which has resulted in it being a constant buzz rather than a rattle (cavitation??) sound. It's been like that for 10k miles so not too worried now but may try M400 pump feeding 044.

[Fett]

So did yours rattle initially? I could live with a buzz, but the rattle sounds more ominous to me. My original pump was silent, wouldn't that have suffered if it was cavitation? The only think I changed is adding a Syntec pump mount.

Maybe I should go back to my old pump and see if it's noisy now. Got my mapping session with Trevor next week so need to get it sorted out.

[TuxMan]

Don't worry sounds like the non return valve !! They do rattle a bit !!!

[Fett]

Is this in the pump itself Simon? Nothing else came with it.

[TuxMan]

Yep mounted on the end of the pump , comes as std .

[Fett]

Don't think mine had one (979), it looked pretty much identical to the original pump, like this:

http://www.competitionsupplies.com/fuel-systems/hi...

Not like the 044? :

http://www.competitionsupplies.com/Search.do?metho...

[R0162]

Like simon says, That is a non return valve, eesy to replace

[Fett]

Sorry but think I'm being a little thick. I cant see what I need to replace. Here's the pump (sorry about the rubbish pics):





Just to clarify I have fitted an M400 pump (Bosch 979) not an 044 pump.

[Rob_W]

Fett said:

So did yours rattle initially? I could live with a buzz, but the rattle sounds more ominous to me. My original pump was silent, wouldn't that have suffered if it was cavitation? The only think I changed is adding a Syntec pump mount.

Maybe I should go back to my old pump and see if it's noisy now. Got my mapping session with Trevor next week so need to get it sorted out.

Changing the mount might be a contributory factor (it's just noise nothing that will affect performance I suspect) . The pump is mounted on a very thin sheet (which I've changed to 2mm aluminium) and sits at the end of the cill which provides a nice chamber to transfer/amplify the noise (I filled mine with acoustic foam).

The NRV is included in the banjo adaptor which you can just see on the left this photo of my arrangement;

[Metalman]

The non return valve is fitted at the end of the pump, where the blue banjo bolt attaches to. You could try mounting the pump clamp on rubber bobbins as I have to stop noise traveling through the floor of the car?

[TuxMan]

They don't all do it. , I refitted my old one on one of my new pumps because it was noisy !!

[R0162]

TuxMan said:

They don't all do it. , I refitted my old one on one of my new pumps because it was noisy !!

same, i had 2 noisy non return valves both new, i tried another and noise went....sound like tiny ball bearings in a tumble dryer very annoying....

[Fett]

Ah I see, eventually! I didn't dismantle the blue banjo part, just attached the new pump straight to it as mine didn't come with another NRV.

I did put some Dynamat down rather than bolt it straight to the floor panel, but guess it wasn't as good as Nobles original 4 cable ties holding the pump arrangement

R0162 said:

sound like tiny ball bearings in a tumble dryer very annoying....

Exactly like that! It is annoying but was more worried that something was wrong. As long as it's ok as is and won't damage anything or effect performance for my remap I can live with it for now. Will try another NRV see if that helps, if not may have to go your bobbin route Jason.

The car felt pretty good though, not sure if it was my imagination though as it was the first time out with my Pro Alloy intercooler fitted.

Thanks for all your help guys. It’s really appreciated.

[Blu3R]

This is my 044 on bobbins:



Still noisy, still rattles, sounds like its f**ked and has done since day 1. When Trevor mapped the car a few weeks ago he said the fuelling was rock solid right through the rev range so I just live with it. I can hear it over the road noise from the Vredesteins at 80!

[Fett]

That's good to hear. Not that it's noisy obviously, but that your fuelling was good even though it rattles.

Took it out again today and the noise seems to stop after about 40-50 mph. I can't really hear the pump itself that much; think it may actually be a bit quieter than my old one. Defiantly is when priming. But my god is that rattle loud on idle!

[Metalman]

Have you fitted the high flow metal filter rather than the standard paper one? Also I read on here that the return port on the tank can be blocked with weld, have you checked it? I checked it by pushing in a drill bit, the biggest I could get in was a 6mm.

[Fett]

Metalman said:

Have you fitted the high flow metal filter rather than the standard paper one? Also I read on here that the return port on the tank can be blocked with weld, have you checked it? I checked it by pushing in a drill bit, the biggest I could get in was a 6mm.

Not sure what type of filter I have, it looks like Blu3Rs above just a red casing and no name on it.I believe Jetstream changed it at my last service, I will have to ask them tomorrow.

Where is the return port and do I need to drain the tank to check it?

[andygtt]

I cant hear my 044's when the car is idling and my car is quieter now on idle than when it was totally standard.

I think we need to establish once and for all why good flowing pumps are noisy on the noble as they shouldn't be if installed correctly.

FunkyBMX pump is as quiet as mine are so it can be resolved.

[Metalman]

It's a simple five minute job, the return is just under the rubber filler neck. Undo the jubilee and pull off the hose, check its not restricted with a 6mm drill bit but don't drop it in the tank!