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Clacking Fuel Pump
dellyend1 - 8/7/19 at 06:19 PM

Hi, Apologies if I have posted in the wrong section, but new to the forum.

I've recently bought a fury and the fuel pump makes an intermittent clacking like it does when priming but does it when running on and off. The previous owner thought it may be the connection from the outlet of the tank to the fuel pipe feeding the pump. I've changed all of that and it seems maybe a tad worse than better.

Any pointers would be appreciated , could it be the pump itself ? I've assumed it would not be any of the connections on the outlet side of the fuel pump as this is pushing fuel through rather than sucking fuel (and air) in. I've got about 10 - 12 litres of fuel in the tank so wondering if it needs to be filled up a bit to stop the noise.

Rather new to all this

Best Wishes

Jeremy

scudderfish - 8/7/19 at 08:31 PM

Hello!

Carbs or fuel injection?

dellyend1 - 8/7/19 at 08:56 PM

Hi, sorry, fuel injection

Many Thanks

scudderfish - 9/7/19 at 10:01 AM

I run fuel injection, but I have two pumps. The old low pressure pump that used to feed the carbs now feeds a swirl pot that feeds a high pressure pump. The LP pump is a noisy thing but the HP is generally quiet. If you only have a HP pump it needs to be mounted below the level of the tank so that it is gravity fed and should never be dry, they don't self prime and use the fuel to lubricate and cool the mechanism. Any photos/video? Where in the world are you? There might be someone local who can take a look.

Excellent choice of car BTW

Regards,
David

nick205 - 9/7/19 at 01:14 PM

Don't most tin tops have a low pressure (lift) pump to move fuel from the tank to the engine and then a high pressure (injection) pump to step up the pressure for the injectors?

Different fuel I appreciate, but that's certainly the way the diesel VAG cars I've had are setup. The low pressure pump is often in the fuel tank itself and you can hear it come on when you turn the ignition on before actually starting the engine.

scudderfish - 9/7/19 at 02:55 PM

A lot of tintops just have the HP pump in the tank. However a kit car made by someone else and all bets are off

jeffw - 10/7/19 at 07:48 AM

quote:
Originally posted by nick205
Don't most tin tops have a low pressure (lift) pump to move fuel from the tank to the engine and then a high pressure (injection) pump to step up the pressure for the injectors?

Different fuel I appreciate, but that's certainly the way the diesel VAG cars I've had are setup. The low pressure pump is often in the fuel tank itself and you can hear it come on when you turn the ignition on before actually starting the engine.


Actually most tintops only have an HP pump in the tank itself.

nick205 - 10/7/19 at 02:34 PM

Happy to be corrected on LP and HP pumps and their locations.

Guess I was thinking in terms of diesel fueled cars I've had and the subject here is petrol fueled.

dellyend1 - 10/7/19 at 03:42 PM

quote:
Originally posted by dellyend1
Hi, Apologies if I have posted in the wrong section, but new to the forum.

I've recently bought a fury and the fuel pump makes an intermittent clacking like it does when priming but does it when running on and off. The previous owner thought it may be the connection from the outlet of the tank to the fuel pipe feeding the pump. I've changed all of that and it seems maybe a tad worse than better.

Any pointers would be appreciated , could it be the pump itself ? I've assumed it would not be any of the connections on the outlet side of the fuel pump as this is pushing fuel through rather than sucking fuel (and air) in. I've got about 10 - 12 litres of fuel in the tank so wondering if it needs to be filled up a bit to stop the noise.

Rather new to all this

Best Wishes

Jeremy


Hi, just to close out the original query (in case anyone ever searches the problem), it was air getting in to the system above the fuel pump with the union and olive that fit onto the tank being the culprit. Having worked out that my Fury has a MG midget tank, I ordered a new union and olive that fits the 1/4' pipe and all is now nice and quiet !. Thanks for all the help. Jeremy

scudderfish - 11/7/19 at 11:43 AM

Glad you got it solved

motivforz - 11/7/19 at 05:42 PM

Hi Jeremy, glad you got it resolved! I was starting to worry that it was the pump on the way out, but air getting in would certainly cause the noise too. Happy motoring!