Two fuel pumps or one?

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Candycj1
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Two fuel pumps or one?

Post by Candycj1 »

Hi all - i've heard that some euro cars only have one pump, no pre-supply. Is there an easy way to tell if my car has one or two without opening up the tank? Car is a late 87 highline with B35 engine.

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plip1953
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Re: Two fuel pumps or one?

Post by plip1953 »

My Highline is a very late '87 build and I believe it has two pumps. Have you tried plugging your chassis no in on Real OEM and see what it lists for your car?
Phil
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bpoliakoff
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Re: Two fuel pumps or one?

Post by bpoliakoff »

Later cars have 2
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Ralph in Socal
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Re: Two fuel pumps or one?

Post by Ralph in Socal »

Remove the round inspection plate on the trunk floor to expose the tank port. If you see nuts and bolts securing the assembly, you have an in-tank pump setup. It may have been modified to remove the in-tank pump but that’s a key visual to determine your setup. This will have 2 sets of wires as well. One set of 3 wires for the level sender and a set of 2 wires for the in-tank pump.

The euro single pump system utilizes a push-in bayonet style level sender with inlet and return plumbing. This will have only the 3 wires going into the tank level sender and no securing hardware as nuts and bolts. Spring-action push-in bayonet style securing of the assembly to the tank.

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Candycj1
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Re: Two fuel pumps or one?

Post by Candycj1 »

Thanks for the replies guys, will take a look under the panel this week when i get a chance to get to the garage. I did look at realoem but it was a bit confusing as it lists options for the main pump with or without the pre-supply.

Cheers
James
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sansouci
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Re: Two fuel pumps or one?

Post by sansouci »

I could be confusing my BMWs, but I think TRE makes a good aftermarket pump.
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plip1953
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Re: Two fuel pumps or one?

Post by plip1953 »

Candycj1 wrote: Tue Dec 29, 2020 10:56 am Thanks for the replies guys, will take a look under the panel this week when i get a chance to get to the garage. I did look at realoem but it was a bit confusing as it lists options for the main pump with or without the pre-supply.

Cheers
James
Did you use your specific chassis number when searching on OEM? Many years ago my external pump was replaced (it was particularly noisy), but there was no mention at the time of a second pump. Furthermore, some years later I had the tank replaced and don't recall any mention of in-tank items that needed to be swapped over. Of course that doesn't mean my car doesn't have two pumps, but it was certainly my strong impression right through until very recently when reading in a thread that related to this particular point.
Phil
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Candycj1
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Re: Two fuel pumps or one?

Post by Candycj1 »

plip1953 wrote: Thu Dec 31, 2020 10:11 am
Candycj1 wrote: Tue Dec 29, 2020 10:56 am Thanks for the replies guys, will take a look under the panel this week when i get a chance to get to the garage. I did look at realoem but it was a bit confusing as it lists options for the main pump with or without the pre-supply.

Cheers
James
Did you use your specific chassis number when searching on OEM? Many years ago my external pump was replaced (it was particularly noisy), but there was no mention at the time of a second pump. Furthermore, some years later I had the tank replaced and don't recall any mention of in-tank items that needed to be swapped over. Of course that doesn't mean my car doesn't have two pumps, but it was certainly my strong impression right through until very recently when reading in a thread that related to this particular point.
Hi Phil - yep, always use the last 7 of the VIN to make sure i get the right parts, even then it had various options for the MAIN pump - country variants (i know i'm not in Saudi or Oz so that's not an issue :D ) as well as both a 'fuel pump' (p/n 16141178751) and a 'fuel pump only with pre-supply' (16141179232) and no obvious clue as to which i need. Of course what i should have done :roll: was look at the page with the pre-supply pump as that seems to clearly state the pre-supply (p/n 16141179424) *is* a fit for my car. Either way, had a quick look under the plastic cover in the boot today and i see 2 connectors so confirm i do have the pre-supply pump so that clears it up. As i'm overhauling the supply i had intended to change it along with the filter, main pump and lines but having seen the price i may reconsider - anyone have any tips on testing it?
Cheers
James
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