240 General: wurring noise coming and going. PLEASE HELLLLLPPPP !

[Andrew (UK)]

OK what happens is this:
The in tank pump is a low pressure pump whose job is solely to keep feeding the main pump with fuel. When the in tank pump fails or stops due to bad electricals then the main pump not only has to push the fuel out but it is now pulling the fuel in as well. This can lead to cavitation on the impeller which is the formation and collapse of small bubbles due to vacuum and hence noise. Cavitation will lead to premature failure of the main pump as it also causes vibration which will ruin the bearings. You may not get cavitation and it may be just that main pump bearings are wearing out anyway. When the main pump fails your car will stop. If you have a suitable ammeter or multimeter then measuring the current through each fuse is a much surer way to check the operation of each pump. The in tank pump is about 1-2 amps, iirc, and the main about 7-8 amps.
There is only one type of in tank pump but there are two types of main pump depending upon the type of electrical connector fitted. If you don't fix the in tank pump soon enough the noise may continue after you replace it due to the main pump's bearings being damaged. But don't think that replacing the in tank pump was a waste of time or not needed, it's good insurance to protect the new main pump you will now be saving up for. I would always fit new as I hate working on the fuel system and will do everything possible to not have to do it again shortly after. Consider getting the complete unit from eBay though as well as a new pump, assuming it is right for your year as they do differ, your present one may be so fragile so as to break while you are removing the old one.

Hi Ive Got Same Prob Not Had Chance To Do Anything About It Yetdue To Slipped Disc.but If You Have Any Tips To Pass On When You Have Done It Please Let Me Know Cheers.mark

[Peter D]

Yes they are the same.. List the carpet under the rear passenger seat and disconnect the main fuel pump power feed, now link the fuses 4 and 6, now listen for the intank pump via the filler. If it is silent then here is the problem. Now remove the wire link. The big problem is removing the corroded in tank unit. Ofter the pump is actually OK it is corrosion of the steel top plate that has expanded and cracked the power lead thru into to the tank. If you decide to disconnect the pipes and remove the tank unit be gentle with the pipes and inspect metal pipes for pin holes and excess corrosion. Regard Peter

[Peter D]

I forget to mention. It is false economy to leave a duff pump in the tank. The noise form the main pump is cavitation and can cause huge turbulanece insife the pump and break blades off the turbine, over £200 for a replacement. Regards Peter

[Clifford Pope]

As might have been said, it's worth thoroughly checking the wiring before finally condemning the pump.
The steel pipes that go through the plate on the top of the tank are very prone to rusting. It is easy to break them while trying to get the rubber pipes off. I'd suggest pouring hot water to soften the rubber, then pinching the sides of the rubber to break the weld to the steel nozzle. Scrape and hoover very thoroughly before moving the locking ring, and then again before lifting the plate. You don't want lots of dirt and rust falling into the tank.
Getting the combined pump and sender unit out is an apparently impossible puzzle, but is actually possible. From memory I think the trick was get the moving arm and float in exactly the right position.

[minesa240x3]

SNAP!! i have a 240se "J"reg B200F,and have exactly the same symptoms,after reading the comments here i now feel confident to try the various remedies,what a wonderful lot you are,TAKE A BOW you deserve it(and you dont charge £50 an hour iether)cheers guys i will let you know if i have any success,good luck minty.

[minty]

Well thats the new fuel pump fitted. Got to say as a very amature mechanic (my ability normally stretches to emptying the ashtray) the job itself i found particuarlly straight forward.
I visited the local scrappers for the intank pump and unit, i chose this option not only because of budget(cost £10) but by removing one it would hopefully give me a few tips on how to fit it.The only problem i did find was the float detaching itself from the main unit and sinking to the depths of the tank where it still lies today. I will have to use the tripometer from now on.
If i can offer any advice it would be as follows.
1, Loosen the locking ring on the top of the unit "THEN" hoover the rust.
2, Remove unit at an angle so the bottom of the unit comes out first and the float last.
3, Test the new pump carefully before fitting in to the tank.
4, Ensure that the sender unit and float are firmly attached to the main body.
5, Remove rust build up and any debris from the locking ring and the top of the unit where the ring fits.
6, """""""KEEP YER FAGS INDOORS""""
Thanks everyone for the help they have given me with this, hope this helps others, Thanks Minty

[Peter D]

Yes the float can get knock off as there is not much room to get it all back in. However you said it sank, it should have floated. Why did you not catch it and refit it to the level arm. Great caution has to be used when testing the pump. If it has been in fuel then running the motor exposes the brushes and commutator sparks to the vapour in the motor and it can go bang. Regards Peter

[asp380]

Originally Posted by minty

Hi, I am now a proud owner of a 240 glt estate (added to my collection of a 740 slaoon and a 480 es).
Can anyone shed any light on to the 240`s very annoying wurring noise that the car emits. I have an idea what it may be.
The noise is really hard to trace, it appears to come from the passenger footwell one minute then the drivers side rear the next.
Must add that the noise at its worst when low on Petrol (just above the red). I would appreciate any advice you have with this "NIGGLE".
Apart from that little issue i am more than impressed with the 240 and find its larger 2.3 engine far more economical than the 740 saloon and probably on a par with the 480`s consumption also.

Hope you can help, Minty

Hi! I'm new here!

I'm abt to buy a 244 GL Sedan Volvo car.

I'm so afraid, because the owner prepared racing cars some years ago, and when I ask him abt the noise he looks "confused" and no words come from him.

In few words: when the engine gains temperature, you accelerate and hear a Singer sewing machine like tick tick in the upper sector.

My question is: would be a connecting rod punch? Or simply valve noise? Maybe she would lost oil pressure, or not. I don't know.

Thank you in advance for any directions, suggestions or advice!

Albert (from Argentina! Yeah!)
http://bmwasp.blogspot.com
http://racingasp.blogspot.com

[loki_the_glt]

Originally Posted by minty

6, """""""KEEP YER FAGS INDOORS""""

I replaced a leaking fuel tank on my brother-in-law's F$%d Esc&*t and when I looked over to ask him to pass me the ratchet handle I noticed him casually smoking a cig while I was wrestling with a tank containing 3 gallons of 4-star plus fumes. Needless to say he got a verbal roasting - and would have got a literal one if the lot had gone up.