in-tank fuel pump

hello,

i've recently had a check-up done on my car and the mechanic told me the in-tank fuel pump was not working (though I can't tell that it's not working). i know how to get to see the top of the pump but i can't seem to get the pump out of the tank, no matter how hard I try. are there any tricks out there to getting a grip on the pump to be able to twist it out of the tank? Also, once the pump is out, how do I go about releasing gas pressure (is that even necessary)? Any words of wisdom before I try this? Thanks!

-Daniel

[Clifford Pope]

I'm not quite clear what stage you are at - you mean you are now looking at the metal plate locked into the top of the tank, or you have successfully removed that but can't jiggle the float and pump assembly clear through the hole?

I'd firstly make absolutely sure the pump is not working first. Have you cleaned the fuse and checked for electrical continuity back to the pump?
If you jump the two fuel fuses (usually 4 and 6) , that will run the pumps continuously. Then you can listen at the fuel filler for a buzz if it is working.

Thanks for the 4-6 tip! I will certainly try it to make sure I don't hear anything out of the tank before moving on. As for actually getting the pump out, right now, I'm looking at the metal plate on top of the tank and I can't seem to twist it out of its position. Any tips on getting that thing to budge without using a sledge hammer ? Thanks for any help you can offer!

[Clifford Pope]

There is needless to say a special tool. So ignoring that, I found the best way was to get some leverage with a very big screwdriver or a crow-bar. Some people recommend using a cold chisel and a hammer, adding the caution that there is petrol not far away so a mallet or something that doesn't spark would be better.
I'm sure it is worth going to a lot of trouble to avoid rust or dirt falling into the tank, so firstly I hoovered all round the access and nearby. Then scrape any loose rust away, and have a go at turning the locking ring. When you get it to move, hoover up any more rust, and finally again just before lifting the unit.

Be very careful of the metal pipes. They rust and become fragile, or get prone to pinhole corrosion. You need to get the rubber pipes off the ends of the metal ones, and that is when you risk twisting the steel pipes because the rubber will be probably be very tight. Squeezing with pliers first sometimes breaks the joint.
The float and pump assembly comes out as one unit. It seems impossible, and even more so to get it back in again, but there is a position you will find by trial and error by moving the float lever about.

[Erling]

Like Clifford says, take care not to create any sparks in this area. People have made tools like this:



The cut-out is 3.25" .The angle gives strength against warping.

[cbyard]

It's also worth checking that it's actually the pump that's failed. When I got mine out it turned out to be the "feedthrough" that carries the current through the metal plate that had failed, not the pump. Needless to say, I'd already bought a replacement pump :-(

If you're worried about sparks it's worth using a brass drift when you resort to brute force and a big hammer to shift the plate.

Best of luck

Chris

[Clifford Pope]

Agreed it's worth testing everything else before assuming it's the pump itself.
Having failed to shift mine by applying moderate leverage, I decided against brute force with a hammer as too likely to break something. I used a 3 foot crowbar levered against a block of wood wedged against the side of the circular access hole. That way I could apply overwhelming force a bit at a time, and stop and suck the loosened rust out before undoing it a bit more.

[Peter D]

It is a common fault that the corroding steel flange jacks up the nylon feed through and cracks the power feel to the pump. Test this by putting a meter in line with the connector inside the car the earth is via the screwed down tab and does not need to be disconnected. The pump should take 1.6 amps and you can here it. Bridge fuses 4 and 6 to power the pump continuosly. If you are not sure about the pump noise then disconnect the main bump connector under the rear N/S passenger seat. However no current then no pump, check you have 12v available at the connector and the current id zero. You can also here the pump via the filler cap.

To remove the pump can be very difficult and if you slip with the tool you shear off the pipes. As Cliff says, clean all around and lubricate. The insert is held in with a locking ring which has tapered long teeth which forces the insert down onto a large O ring. Use a long tough screw driver and locate it in the slot at about 3 o'clock and tap the locking ring anti clockwise, once it starts to move the tap the 9 o'clock slot and slowly rotate the ring until it is loose and carefully extract the whole assemble, very fiddly. Should you break the unit Volvo want in excess of £240 for a new one. If you do havve a broken feed through then with care and good engineering you can repair them but some choose just to add a wire through a new hole in the insert and alaldite around the wire on the top surface and feed the wire though to the power feed connector. Not my style. If you test the pump out ogf the tank beware it is full of petrol fumes and can go with a bang when ignited by the sparks from the brushes. ( DC Brush Motor ) Take care. As Cliff details the metal pipes are prone to seriuos corrosion and pin holes. Regards Peter