Write-up: Stock replacement fuel pumps

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mitch_f1
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Write-up: Stock replacement fuel pumps

Postby mitch_f1 » Sun May 10, 2015 10:26 pm

The title should read universal fitment fuel pumps, because that is essentially what they are, unless you spend 2 arms and a leg getting a genuine one.

I write this because I found precious little information on the topic, so here I go sharing my information so that others may learn.

Firstly, you really need to be super careful working with anything related to the fuel system. Please read your workshop manual carefully before attempting and wear non-synthetic clothing and have a fire extinguisher next to you.

Also, my car is a JDM NA6, so unsure how applicable this is to other makes, but my fuel pump assembly looks like this with the conical connector to the fuel pump rather than a small length of fuel hose:
Image

There are several pumps available off the shelf from the likes of Repco, Supercheap etc. The ones I have tried are the BOSCH and DENSO ones, but I was also told of a Fuelmiser one, but unsure about it.

The first one I got was the BOSCH pump because of its cheaper (than DENSO) price I couldn't go past it. When I was installing it I realised two things, first the kit does not contain a replacement o-ring. What you get is:
-fuel pump
-two different size filters (and lock washer)
-small section of rubber hose and two hose clamps (which you won't use anyway, at least on an NA)
-new wire clip with two bullet crimp connectors

When going to fit it the second thing I realised is that the filter was facing the wrong way which meant that it wouldn't fit into the tank.

After doing some more research I found that the DENSO pump came with the o-ring, and new grommet beneath the o-ring, but also that it might accommodate a filter which points the same direction as the stock one. However, the wire clip does not have the bullet crimp connectors, instead just had two exposed wires.

Side bar on electrical connections: Bullet connectors are okay in the fuel tank. Do not use heat shrink as it will melt in the fuel. Fuel resistant bullet connectors are the way to go. Otherwise, you could go about offsetting the wire connections to be extra safe. Also, on an installation note be extra careful to make sure that the wires do not impede the travel of the fuel float otherwise your gauge will show full when you run out of petrol.
Image

In fitting the DENSO pump i realised that I was mislead about the filter direction (it's so difficult when there is next to no photographs of the products on the internet). So at this point I realised that I needed to re-use the stock in tank filter after a bit of clean.
Image

Also, I also was tearing my hair out trying to remove the tiny screw which holds the fuel pump in, as it was bonded to its hole with some kind of inhuman strength. So it was replaced with a hex head bolt I had lying around. So just so long as you're aware you might have to fight it.
Image
Image



So cliff notes:
If you are attempting this job first make sure you have the following:
-BOSCH fuel pump (due to the superior connector and cheaper price)
-O-ring (B61P-13-ZE5) (this is like $20 on Amayama, so maybe try find a non-OEM one??)
-new in tank fuel filter (B61P-13-ZE1)

Hope that this has helped :)

Image

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Re: Write-up: Stock replacement fuel pumps

Postby manga_blue » Mon May 11, 2015 1:03 am

Thanks for the write-up. I used a Walbro 190lph with an NA8 Miata fitting kit from ebay US. Absolute direct swap with zero fiiting issues. http://www.ebay.com/itm/Walbro-Mazda-Mi ... 2a&vxp=mtr
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Re: Write-up: Stock replacement fuel pumps

Postby bartmanftw » Mon May 11, 2015 3:01 am

Nice write up. That screw is a real pain to remove and very easy to thread so I also replaced mine with a hex bolt.

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Re: Write-up: Stock replacement fuel pumps

Postby pezchops » Mon May 11, 2015 9:58 am

thanks for taking the time to take pictures as you did the job.
that is really usefull for first timers.
a sponsor here also sells generic pumps at a very good price,plug and play ,but reuse the old filter.
another tip is to remove the passenger seat first up to give easy access.

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Re: Write-up: Stock replacement fuel pumps

Postby Mr Morlock » Fri Jun 26, 2015 6:35 pm

I would think the Denso pump is OEM and maybe a quality pump. Sounds like a job one does not want to do again.

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Re: Write-up: Stock replacement fuel pumps

Postby Xaviien » Tue Jun 30, 2015 11:18 am

pezchops wrote:a sponsor here also sells generic pumps at a very good price,plug and play ,but reuse the old filter.

Would you happen to know which sponsor it is?
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Re: Write-up: Stock replacement fuel pumps

Postby hks_kansei » Tue Jun 30, 2015 2:01 pm

A friend purchased a direct fit pump from a sponsor last year sometime, and although it was priced about the same as the Bosch/Denso/Fuelmiser ones, it had the noticable disadvantage of burning itself out after 3 months.
Pretty sure it was just a chinese pump/kit.

Personally, I'd prefer use a better brand, more reliable pump, like the Bosch or Denso and just deal with the minor hassle of fitment (which you'll only need to do once anyway)



From memory when we helped change the pump for my friend we put in a better one (Bosch/Denso/Fuelmiser, cant remember which)
The new filter sock was fine, no need to reuse the old one. It did need to be bent into place however, but the stock pump was no different in that regard when it came out.
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Re: Write-up: Stock replacement fuel pumps

Postby TrackAttack » Thu Jul 02, 2015 1:32 pm

hks_kansei wrote:The new filter sock was fine, no need to reuse the old one. It did need to be bent into place however, but the stock pump was no different in that regard when it came out.


I think you'll find if the filter sock bent when fitting, it was the wrong way around. When looking at the filter, if its the correct orientation, the filter covers the little clip that holds it on, however if it is a generic strainer, the strainer faces away from the clip, fouling on the inside of the tank.

Correct:
Image
Incorrect, but most common:
Image

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Re: Write-up: Stock replacement fuel pumps

Postby Nevyn72 » Thu Jul 02, 2015 2:17 pm

hks_kansei wrote:A friend purchased a direct fit pump from a sponsor last year sometime, and although it was priced about the same as the Bosch/Denso/Fuelmiser ones, it had the noticable disadvantage of burning itself out after 3 months.
Pretty sure it was just a chinese pump/kit.

Personally, I'd prefer use a better brand, more reliable pump, like the Bosch or Denso and just deal with the minor hassle of fitment (which you'll only need to do once anyway)

I've read good things about the Deatschwerks pumps. (There's an MX5 specific kit avilable too)

Higher flow than factory but just as quiet as the OEM unit. The Walbro for example is renowned for being a little on the noisy side......

http://www.deatschwerks.com/products/fu ... 200-detail
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Re: Write-up: Stock replacement fuel pumps

Postby mx589 » Thu Aug 13, 2015 1:07 am

Magnablue how noisy is your walbro pump I've used them in some other cars and worried on a mx5 behind the seat maybe noisy as.

Do you remember the model number you used.

I've used the gss342 in a few other cars before and it's a great pump for the money

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Re: Write-up: Stock replacement fuel pumps

Postby manga_blue » Thu Aug 13, 2015 5:50 pm

No noise at all. It's the 190lph model from a genuine Walbro dealer. This one: http://www.ebay.com/itm/250383206698?it ... 60&vxp=mtr

There have been a lot of problems, including noise and bad performance, with the Walbro 250lph models. That may be because it's a popular mod for muscle cars and there are so many fakes for sale.
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Re: Write-up: Stock replacement fuel pumps

Postby hks_kansei » Thu Aug 13, 2015 5:59 pm

Had to do mine the other week, got a Denso.

To be honest, not sure i'd go another one (for NB anyway) as I had to modify and change a few bits.


First difference was the plug, no big issue, but the lack of any wiring connectors was a really annoying bit, since not having a running car meant going out to find fuelsafe connectors was out of the question.
ended up using some wurth click connectors and wrapped the positive one with some fuel hose so that if the connectors do dissolve in the fuel it wont short on the pump etc. (actually got my GF to do this part, since if I wired it it was a certainty to short)

The next issue was the filter, as said above. This was actually easy, just reused the OEM one.

The final problem was the rubber thingy on the bottom that locates the pump.
The Denso one wouldn't fit the mazda bracket, the mazda one wouldnt fit the denso pump (Mazda one had inner profiles, where the Denso was flat)
I had to sit down with the OEM rubber thing and very carefully carve out the OEM channels and make the inside flat (OEM pump uses the rubber to channel fuel etc to the little pinhole (presumably a bleed hole), where the Denso has a cast metal channel)

After all that it fits and works fine.

But yeah, there was a lot of farking around for what should have been an easy job.
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Re: Write-up: Stock replacement fuel pumps

Postby gslender » Thu Aug 13, 2015 10:46 pm

TrackAttack wrote:
hks_kansei wrote:The new filter sock was fine, no need to reuse the old one. It did need to be bent into place however, but the stock pump was no different in that regard when it came out.


I think you'll find if the filter sock bent when fitting, it was the wrong way around. When looking at the filter, if its the correct orientation, the filter covers the little clip that holds it on, however if it is a generic strainer, the strainer faces away from the clip, fouling on the inside of the tank.

Correct:
Image
Incorrect, but most common:
Image


This is worth knowing as I recently changed mine and had heaps of fuel surge/starvation issues on the track until I put the correct filter bag on and then it was fine with zero surge issues. So yep, fit the correct OEM filter.


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Re: Write-up: Stock replacement fuel pumps

Postby CrazyRacer » Sun Nov 15, 2015 12:52 am

Just replaced the one on my NB8A with a new bosch pump, part number 0 986 580 979.

I ordered it directly from the online Bosch shop at http://au.bosch-automotive-shop.com/ for $62 which is pretty cheap. They were slightly cheaper on eBay, but I figured that buying it direct from Bosch would ensure its genuine (not that I'm sure there are any Chinese rip offs of these).

Old one was still working, but had a lot of kms on it and I was fitting a BD rollbar which covers the access plate, so for $62 figured I'd do while it was easier.

Fits perfectly and works great with no noticeable noise from it.

The crimp connectors for wiring were supplied. As mentioned above I did have to re-use the sock filter as both supplied ones point the wrong way. I ended up also having to re-use the old bit of hose as the new one supplied was too small in diameter.

Job took a little over an hour to complete with me figuring it out as I went (but this guide was helpful) and was pretty easy, but messy.

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Re: Write-up: Stock replacement fuel pumps

Postby Magpie » Mon Nov 16, 2015 8:14 am

Been posted on here before but



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