Hi guys.
A bit of advice please. On my way back from a car show today I noticed I could hear my fuel pump running. Not particularly loud but noticeable and I haven’t heard it before while driving the car. No issues with the actual running of the car it was perfect and even returned a tad over 20mpg according to the fuel computer. When I got home I also noticed I could hear the returned fuel running into the tank. When I first got my car I cleaned out the small tank adding a new pick up filter. It was very clean so no worries there. I also replaced the main fuel filter at the same time. All this was done probably around 1500 - 2000 miles ago. I tried a bite later after things had cooled down and the pump sounded normal but I could still hear the returned fuel running back into the tank. Any ideas?

Rob.

 

Fuel Pressure Regulator? Pull the vacuum hose off of it. If it's wet, or smells of fuel....its time.

Actually, thats six cylinder advice. I'm not familiar with the v12.

 

A fuel pump becoming louder than normal probably isn't a good thing. It might be showing some age. Or...perhaps struggling against a partially clogged filter.

Not sure why you'd begin hearing the fuel return when you've never heard it before. Odd. I'm a bit surprised you can hear it at all.

Cheers
DD

 

Agree with Doug.

Age is against that pump now, just like those sensors.

NOT unique to Jaguar, BM, Merc, Ford, GM, etc all used that thing.

Restricted filter, YES, and age again can be the gremlin. About 5 years is the average down here.

Return fuel, NAH, you drank to much at the BBQ mate..
With the cap off, hearing aids at full volume, maybe????, via the filler spout, but that maybe is a BIG maybe.

 

Cheers guys.
Grant no beer I’m afraid just tea. Pick up filter in the sump tank should be fine as replaced when the tank was cleaned out. Main filter was replaced at the same time. I didn’t hear the pump on the way to the show yesterday but noticed on the way home. At first I thought it was the secondary fan running but it didn’t switch off then when I got home I noticed it was coming from the rear. Definitely heard some sort of fuel noise. I noticed it when the ignition is turned on and the pump runs to prime the system there was some sort of gurgling noise from the tank. This was hot and just switched off from the run home. Looks like a new pump them. Any suggestions as there are loads out there £25 up to over £100.

Rob.

 

Rob,

TEA?????? there be the problem, unless it was "added to" behind the scenes, hahaha.

GE034 Goss is one brand I have used. Last one $125.

0 580 464 070 is the Bosch I prefer. One needed 4 years ago, $119.

The "cheapies" are just that, sadly, and I will leave it at that.

?bay is good., SNG, Manners (Jack Masters) to name a few.

Other sponsors of this site will also work, but, as I said, NOT unique to Jag in any way.

 

Rob,

Forgot, unlaced tea does that.

When its noisier, remove the filler cap, LISTEN, if it quietens down to "acceptable", I reckon you have a tank breathing, or lack of, issue.
These umps are NOT suckers, they rely on gravity feed, and if that flow is lacking, they will be noisy.

We drill a 1/64" hole in the cap, BUT, you got MOT, Bugga, so you are screwed for the Aussie fix.
BUT
One cap for MOT, another (Aussie style) for the rest of the time, works for me.

 

Hi Grant.
I actually have a very small hole drilled in my cap after reading a post by Greg I think and it passed its mot just fine so no probs there. I will chuck a new pump in there as it’s no doubt the original so 32 years old isn’t bad really.

Rob.

 

Robbo
A proper good make for the pump. Bosch or Walbro. Orangeblossom buys el cheapo ones and they have been fine, but I think he was born under a lucky star!

 

Morning Greg.
I think I will go for the Bosch pump. I have always liked Bosch stuff we have a kitchen full of it ha ha. Still not sure of the petrol noise though. Will go and have another listen in a bit. It’s a Bank Holiday here so off work for the day. Just got to take the hound out for a walk then in the garage to clean the car up ready for the next outing.

Rob.

 

Hi Robbo

'El Cheapo' always works for me! £25! and I always carry a Spare one just in Case

I've also moved the Pump over, so its easy to get to if I had to change it by the Side of the road

Your problem is possibly a Blocked Fuel Filter, so I would change that first and see if that makes any difference

Advice from a Fellow Tea Drinker!

 

Hi OB.
All filters are only 1500- 2000 miles old changed when I checked and cleaned out the sump tank which was vey clean anyway. I can afford a Bosch pump now as I just found a £20 note laying in the hedge on my dog walk this morning. I live in the country side so don’t know where it came from.

Rob.

 

Hi guys.
An update. Now had the spare wheel out and removed the battery covers. Pump sounds normal during priming and at first start then after about 2 or 3 minutes is louder definitely louder. If I put my hand on the filter I can feel as well as hear what I think is air bubbles moving through the filter. That actual car runs fine smooth as silk but I’m not sure about what feels like air. Maybe that’s how they are I don’t know.

Rob.

 

I should have added that the only other thing is I’m running a Lucas injector cleaner in with this tank of fuel.

Rob.

 

That is interesting.

Pump aeration is not uncommon, BUT, usually there is a fuel leak when not running. Especially these gravity feed systems.

IF, and there is no reliable way to look inside, that sump tank is NOT filling from the Main Tank, then the pump will be getting aerated fuel supply.
There is a Vent hose on that small tank to allow proper filling, worth looking etc, and see what you find.

Its obviously OK when first started, and then as fuel is used, the sump tank is dropping, and the pick up is not fully covered by fuel. A partially blocked breather pipe will do that, preventing gravity fuel from the Main to flow to the Sump.

 

Hi Grant.
You have confirmed what I was thinking but surely this would affect the running of the car. I can confirm that she runs beautifully. I have now noticed something else which might be related. When the pump first runs I can hear fuel going through the system in the engine bay. Now it might have always made this noise and I have never noticed. Just had a suck on the LH FPR and it holds vacuum but I can taste petrol slightly.

Rob.

 

Rob,

It only takes a SMALL amount of air to give the pump a head ache. The amount of fuel being supplied to teh front is HUGE, and under normal driving conditions 2/3 is returned to teh tank.

Proper V12 driving, AKA Greg style, about 1/3 goes back, ROUGHLY.

That engine is fine, and when the aeration is sorted, will be better.

The fuel flow noise is normal. Thinsg bleed off overnight, and in most, after a few hours.

Fuel taste at the FPR vac is a sign of age related failure creeping up again. I would source one, and replace it, as failure can flood the engine, NOT good. Average life, with todays lousy fuel is 10 years TOPS.

 

Cheers Grant.
Age related I know the feeling🤣 Again both look original so ready for a change. I know I can do away with the RH A bank but I like the car to look original. My plan of action with the pump and air is to check out the feed pipe from the main tank to the swirl tank. I wouldn’t mind fitting a tap in there so I can isolate the main tank in the future but will have to see if I can get something suitable. While sorting this I will also check out the sock filter in the swirl tank and remove but fit an inline filter before the pump one of those see through plastic things should do the job? That way I can see what’s going on. Plan good or not???

Rob.

 

Rob
First make sure you can source 1/2 inch feed pipe, this is not that easy to find. The thing I have done is to use a 1/2 inch inlet/outlet WIX 33248 inline fuel filter between the tank and the sump tank. Then you can do away with the sump tank filter. I do not recommend a smaller filter as they will not flow enough.
A tap in this 1/2 inch feed seems a good plan, but I have nevr been able to find a tap that will not leak. Pic here of my system, which clearly shows the filter:


Rockauto details
https://www.rockauto.com/en/moreinfo...&pt=8600&jsn=1

Amazon

 

Hi Greg.
I would really like a clear filter if possible but having looked online I have only managed to find 1 with the 12mm hose tails and can’t seem to find a decent tap/valve. There a some on eBay but look like they belong in an airing cupboard 🤣 definitely not to be trusted with petrol. I will ask some of our agricultural suppliers tomorrow when I’m at work and see what they come up with. I will of course let you know how I get on.

Rob.