Fuel Pumps

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Rearwheel_nick
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Post Tue May 24, 2005 3:41 pm

Do some models have the fuel pumps in the lil access hatched under the rear bench?

i have a soap bar shaped access point on the drivers rear side....and a round shaped one on the passenger rear side... in haynes manual its showing a kidney shaped access panel......so am i right in thinking my fuel pump is under the tank somewhere and i have to access it underneath...i cant really get my head under there to look at the moment.

cheers in advance again guys
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bennyp
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Post Tue May 24, 2005 3:47 pm

under the rear seat my 325 has two hatches also.

the pump on mine is under the hatch behind the drivers seat ( oval hole ). think the other one covers the petrol gauge sender or summit like that(?) :?
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Rearwheel_nick
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Post Tue May 24, 2005 4:08 pm

if its any help mines an E reg 320 but with 2.5 engine in it.

see i pulled something out of the hatch behing the drivers seat, and it was like a white semi-cylindrical sort of thing... didnt look very pump like....unless theres something else i have to pull out.
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bennyp
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Post Tue May 24, 2005 4:13 pm

my pump is a sort of khaki colour and has an funny shaped filter on the bottom,

apart from that im no help at all......... sorry :oops:
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Brianmoooore
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Post Tue May 24, 2005 9:35 pm

E reg is right on the changeover. Early cars had a transfer pump in the tank, under the hatch behind the drivers seat + a high pressure pump underneath the car just in front of the rear left wheel arch.
Later cars have a high pressure pump in the tank, under the driver's side hatch only.
If you have the early type, you should be able to hear the pump easily from outside the car when the engine is running.
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Rearwheel_nick
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Post Tue May 24, 2005 9:54 pm

cheers dudes... i must have early car then from the sounds of it...

out of curiosity is the later style interchangeable with the early sort.. i have come across a 325 tank and pumps ..which according to you are the later kind.... could i fit that to mine.. or is it just too much effort.
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Brianmoooore
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Post Tue May 24, 2005 10:04 pm

Yes, easy to change over. You will need to remove the pump from under the wheel arch and replace it by a piece of high pressure fuel hose, and do something with the electrical connector to the pump.Also check that the outlet from the later pump is connected by high pressure hose as well.
Can't remember if the electrical plug to the old transfer pump will fit the new pump or no.
Note, you have to unscrew the four small nuts on top of the pump mounting plate, and withdraw the fuel level sender first, before you can remove the pump from the tank.
Do the changeover with a nearly empty fuel tank, have all the doors open while you do, and beware of sparks. (door light switches are a possibility).
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Brianmoooore
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Post Tue May 24, 2005 10:10 pm

P.S. There are two versions of the in tank pump assembly. Some have a connection for the return pipe from the fuel pressure regulator, and on some cars it enters the tank by a different route.
IIRC the 320 pump only has an outlet, while the 325 has an inlet and outlet. No problem, but you need to blank off the unused inlet, if your new pump has one.