fuel pump location

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jtparr
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fuel pump location

Post by jtparr »

hi

enclose a couple of pictures, just to prove I am doing something, albeit slowly.......:lol:

also shows a trolley I had made up whkch will allow it to travell to bodyshop, made of 50mm tubing and wheels from screwfix it was £230 of which £80 was the wheels, rated at 250kg each


grey paint is the POR 15, generally 2 coats which is being done on the car in sections, on the good bits of the body, prior to having the rusty metal replaced, at which time the rest gets POR 15 prior to stone chip and body colour (metal having been cleaned down to bare state first, treated with POR 15 metal ready prior to the grey paint finish)



my question is about the fuel pump, on the near side

has anyone ever relocated the fuel pump from the bracket welded onto the torsion tube. Its a fantastic place for rust to develop as it just traps muck, and makes cleaning around it difficult
I'm wondering why the bracket cannot be cut off and the pump located inside the engine bay

any thoughts welcomed

ps you'll also notice some of the bent tabs that hold the wiring loom missing from the offside seat pans and that the U shaped brackets for nearside wiring loom are unpainted as I am going to relocate these as well, as they are a similar bad design for trapping muck

thanks

Jp

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Nige
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Post by Nige »

I think you'll find that its located underneath the fuel tank because its designed to push the fuel to the back of the car rather suck it from front to back. Also if you locate it to the engine bay you are lifting it above the level of the tank and reducing any gravity fed effects as well.

But I'm sure you could by a new pump that is better designed for an engine bay installation.
1972_911t
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Post by 1972_911t »

What about relocating it the front of the car under the cover for the brake servo where they are on the post 74, cars, This wouldnt be too hard and would make the pump more efficient. I have just moved mine to the smuglers box as my car is a left hand drive there a bit more room in there than under the front pan. I also anglegrinded that bracket at the back off.

Steve
1972 911t RS Styled + G50 Converted
SAAB 9-3ss Aero
jtparr
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fuel pump location

Post by jtparr »

nige

yup think you have a point there, there is a unit under the tank I had forgotten about / overlooked...... :oops: so whats the one at the back I wonder...... :? .......help anyone !!


steve

like the sound of it, excuse me being a bit dense this morning but where is the "smugglers box", (mines a RHD 1975 year model, but has the pump at the back but it does not have the brake servo in the front trunk)

when you say you moved your pump, did you just move the original item or did you buy a new and different one ?

thanks a lot


Jonathan
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Post by 1972_911t »

The smuglers box is something they have on left hand drive cars it is located under the bonnet under another cover, its where the air conditioning unit or the auxilary heater was on the early 911's in front of the pasenger footwell. The right hand drive cars did not have a smuglers box.

My car does have a different pump as I have a 3.2 engine in my car this is the main reason I switched my pump to the front. however if you were intent on moving your pump moving it to the front would be the best idea. As porsche found out on later models the pump works more efficiently when located nerer to the fuel tank. All 911's 74 to 89 and maybe later have to fuel pump attached to the front cross member just below the fuel tank to the back where the servo is this would provide the best location if relocating the pump.

Steve
1972 911t RS Styled + G50 Converted
SAAB 9-3ss Aero
jtparr
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fuel pump location

Post by jtparr »

hi again

last night i checked the car and took the following pictures this morning

my car, though a 75 year model seems to be a bit between one design and another, it has the later type of pump (I think), but the earlier steel type of front suspension cross member, which then means the pump is still located at the back of the car...... :?



Image

so, first picture is of the pump in detail, the top pipe is the return feed to the fuel tank I think (smaller bore) and the lower one (larger bore) is the supply feed from the fuel tank, the middle pipe conects to the fuel filter

Image

second picture is the pump and filter with their connecting pipes (all lovely and rusty from 31 years of exposure..... :( )

my question now is, whether with this system can I simply relocate the pump to the front, because instead of the existing, longer plastic pipes being through the transmission tunnel, between the fuel tank and the pump, the longest length of pipe will now be between the pump and the the filter....... :shock:


anyone have any thoughts ?


thanks


Jp
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Post by Gary71 »

I would assume as long as the height relative to the tank is maintained then it should function equally well at the front of the car.

Don't hold me to that though! :)

P.S your pump looks identical to that fitted to my '72.
1972_911t
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Post by 1972_911t »

Yes it could be done easy, the biggest problem would be that the supply line that comes from the front of the car is bigger bore 5/8 I think this is to stop restriction of supply to the pump when its located at the rear. The outlet from the pump is 1/4 so you would need to step this pipe up after the outlet from the pump. The second outlet from the pump would then go to your T piece which you would relocate to the front, your t piece would then go to the tank return with the other one coming from the soild return from the back of the car. Keep your filter at the back then its just simple supply and return at the back of the car to the filter unit. Your pump will then work more efficiently as its not sucking fuel all the way from the front, pumps are designed to pump not suck!

Steve
1972 911t RS Styled + G50 Converted
SAAB 9-3ss Aero
jtparr
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fuel pump location

Post by jtparr »

steve

thanks a lot for that, sounds pretty straight forward which is great, can I just ask one clarification please, when you say


“your t piece would then go to the tank return with the other one coming from the soild return from the back of the car”

what do you mean by

“with the other one coming from the soild return from the back of the car”



thanks again

Jonathan
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Post by 1972_911t »

That T piece in your picture is the return T piece the system has 2 returns that are T ed into one. The first return is the second outlet from the pump joined to the T piece that is currently shown attached to your pump , in the original location one return would come from the pump and the other is returned from the fuel filter these both T together and the join to the solid line that returns them both to the fuel tank. So the only thing your doing different is taking the return from the fuel filter unit straight to the solid line through the car and T ing them together at the front instead of at the back then as before they both return into the tank.

Go to this link good diagram of fuel system makes it nice and clear

http://www.pelicanparts.com/techarticle ... er_MFI.jpg

Steve
1972 911t RS Styled + G50 Converted
SAAB 9-3ss Aero
jtparr
DDK 1st, 2nd and 3rd for me!
Posts: 2237
Joined: Mon May 24, 2004 10:54 pm
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fuel pump location

Post by jtparr »

steve

many thanks, very much appreciated, angle grinder will be seeing a bit of action then this wekend :lol:

Jp
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