Fuel Pump Mod Completed - Pump now noisy

[Rob_W]

As per the title I completed the wiring mod at the weekend and the pump is now very noisy. IS it the shock of seeing 12v for the first time? Is it likely to die? If so what to replace it with Noble part or Bosch 044?

[BobE]

Did you remove the pump to do the wiring upgrade and if so was it replaced with the same foam etc to prevent noise transmission in the body panels?

[Rob_W]

No, only had to remove a couple of the cable ties and replaced them afterwards.

[Jim O.]

Check the feed line to make sure there aren't any kinks. Also check the return line for the same thing. Also, if the UK version is anything like the US version, the fuel pump is mounted on a segment of tubing that's bolted down to the middle of the aluminum panel under the car. Problem is, the ends of the bolts stick up inside of the segment of tubing, eventually cutting through any foam insulation wrapped around the fuel pump. Once the bolts cut through the insulation, they dig into the side of the pump, transmitting all the pump noise directly to the aluminum panel, which acts like a big sounding board. What we usually do is remove the segment of tubing, remove the bolts, and weld the bolts to the outside of the segment of tubing, so that the inside (where the fuel pump sits) is smooth. Replace the foam, maybe add some more sound/vibration damping material. Make sure the aluminum panel under the car is securely fastened, maybe add some sound/vibration damping material (like DynaMat) to this panel, etc.

Or, your fuel pump may be on its last legs...

[Rob_W]

Hi Jim

Thanks for the latest therapy session.

Fiddling around may have affected the mounting (which is as you describe)but I doubt it. Will do so form of mod as you describe (when I get the car back from getting the aircon fixed!).

Is it also worth cleaning/replacing the filter?

Dumb question; To do the filter or pump do you clamp off the feed from the tank or does that damage the feed pipe?

Thanks again

Rob

[jamescmr2]

The pump could be noisy if it were sucking in air from a loose fitting, damaged pipe etc?? worth checking everything.

James

[Rob_W]

Thanks James. My thinking is that if the pump is working better it is now picking up a pre-existing issue. Will check through. Can you advise on the question re. Clamping the fuel pipe as I don't want to make things worse by weakening the pipe; haven't dabbled with fuel systems until now.
TIA
Rob

[Jim O.]

Rob_W said:

Is it also worth cleaning/replacing the filter?

Dumb question; To do the filter or pump do you clamp off the feed from the tank or does that damage the feed pipe?

Yup, it's definitely worth cleaning the filter. I usually just empty the tank before removing the filter. It's pretty easy, now that you have your relay in place. I disconnect the hose from the fuel rail, stick a rubber hose onto the fuel rail connector, put the other end of the hose in a gas can, then jump the relay to turn on the fuel pump.

[andrewr]

Check that when you re tiewrapped the pump that it didn't slip backwards as the end of the pump can easily touch the inside of the removal panel trasferring noise to the cars frame.

[andygtt]

Check you dont have the same issue as me as when I was reassembling mine Im absolutelly positive a couple of bees crawled into the pump and they often get very angry

[jamie g]

Daddysumo had a problem woth the return line being restrictive. He recommended to pull off the return pipe from the tank and see if the noise changes. If the pump goes quiet the tank may need reworking. Obviously you'll have to feed the fuel pipe into a suitable container.

[Rob_W]

Thanks for all the input and will check it all out but I drove home from the garage at lunchtime with a noisy pump but as soon as I waved a spanner this evening everything purring like a kitten. I'm sure they know when you're going to do something! No doubt it will come back. Moved on to my other job, see other thread.

[Rob_W]

Jim O. said:

[ I disconnect the hose from the fuel rail

How? Build manual says it's a push fit but it doesn't seem to want to come apart, is there some trick to it?

[daddysumo]

Rob_W said:

Jim O. said:

[ I disconnect the hose from the fuel rail

How? Build manual says it's a push fit but it doesn't seem to want to come apart, is there some trick to it?

You really need a special tool to release it.

[Rob_W]

daddysumo said:

Rob_W said:

Jim O. said:

[ I disconnect the hose from the fuel rail

How? Build manual says it's a push fit but it doesn't seem to want to come apart, is there some trick to it?

You really need a special tool to release it.

Ah thanks Dad, good job I didn't persist with the brute force route.

Anybody got any alternatives? disconnect at pump and shove a piece of tube onto that?

[Jim O.]

Rob_W said:

Jim O. said:

[ I disconnect the hose from the fuel rail

How? Build manual says it's a push fit but it doesn't seem to want to come apart, is there some trick to it?

Yup, there's a special tool that releases the fitting - it slides in from the rail side, and moves a spring out of the way so that the connector can come off. Tool is pretty cheap - you can get a plastic one for a few bucks. Or, you can get a little piece of metal tubing (something that fits around the tube coming off the fuel rail, around .063" wall thickness), split it in half lengthwise, put it around the tube coming off the fuel rail, and push it into the connector, then pull off the connector. Or, use something like a thin, flexible piece of plastic, like a piece of a juice container, beverage bottle, or oil container. Cut a piece, wrap it around the tube, and slide it into the fitting until it bottoms out, then pull the fitting off the rail. I've even heard of people using a piece of a beer can, but I haven't had beer out of a can in ages, so haven't tried this one out...

[Jim O.]

Rob_W said:

Anybody got any alternatives? disconnect at pump and shove a piece of tube onto that?

You can also disconnect the fuel return line and use that to carry fuel into your jug. Or disconnect the fuel pressure regulator from the Tee in the line, and hook your hose up to the Tee. I like to use a point fairly high in the car - that way, when I disconnect it, not so much fuel comes out. You can go right off the pump, but more fuel will leak out.

If you want to, you can even disconnect the line feeding the pump, either before or after the fuel filter, and cram that into your jug and let gravity do its thing. However, if you have more fuel in the tank than fits in your jug, there's no good way to stop the flow - if you use your fuel pump to empty the tank, when your jug fills up, all you have to do is turn off the pump...

[daddysumo]

The easiest way to stop the flow, which works for me is to bung up the breather pipe which exits under the car near the fuel pump, with a bolt or some such thing,make sure your filler cap has a good seal and locked down, then pull the pipe from the pump or where ever, you might get around half a litre or so , then that's it,as the vacuum caused above the fuel in the tank stops any more from escaping.

THT

Steve

[Rob_W]

Steve, Jim

Many thanks again, will get back onto it tomorrow night.

Rob

[qmusmar]

Hello
I am new to the forum and have a few questions about the fuel pump mod. I own a 2006 noble m400 and just love the car. Any help would be greatly appreciated
What type of relay is used?
what gauge wire is used to wire the relay?
does any one have a wiring diagram?