Installing the fuel sender O ring in R34 GTT

[DraftySquash]

Another weekend and another project I have questions about....

I bought a fuel tank sender O ring to install on the car because I'm quite sus on what I've got now. 
1. No "whooosh" sound when opening fuel cap
2. If I fill up full tank, there will be a small leak under the car and it comes from the top of the fuel tank, dripping along the side. Stops after a short while
3. Hot days = 50/50 chance to get high as a kite inside the cabin if the car was in the sun for too long

This is what I bought: https://www.amayama.com/en/part/nissan/1734279900



My plan was to just replace the O ring but I've got some questions:
1. Does the whole fuel pump assembly need to come out for me to replace the O ring?
        Or, could I unplug all the connectors and fuel lines at the top, take off the twisty part (17343) and put in the O ring from the top? 

2. Is it a very common thing for everyone to just change the pump whenever doing this?
       I see the Walbro 255 gets thrown in a lot but I've got no issues with my pump so far. When I did the tune, I asked the guy to check my fuel pressure and he said there were no issues too. But is it just a good idea to change to the 255 anyway as the old unit may have been in there for so long? The 255 seems to be a direct fit for GTT (I got no soldering iron)
 

[Duncan]

1. No, as you say you can remove the connectors and fuel lines. Before you do make sure you remove fuel pump fuse and crank the starter a few times to release pressure, and also loosen the fuel cap (just in case the tank is slightly pressurised) as it will pump out the lines otherwise

2. Not necessary but you are right, if it is the factory pump it is at risk of failing after 25 years....Changing it is not hard but potentially not trivial as you have to make sure you have the right pickup/sock for the pump to suit the tank, need to make wiring connections (crimped butt connectors would be fine) and have to mount/adapt the new pump in the right place in the cradle. Not impossible but don't start the job if you aren't confident.

Also, the plastic nut that holds that seal in place can be really hard to remove. If you don't have a fuel nut removal tool it generally requires a big screwdriver or similar to bash the ring around a few times before you can get it by hand. Also the fuel lines can be very sticky on the tank lid fittings, hose removal pliers can help or if not twist the hose on the fitting (eg with linesperson's pliers) to break the seal before you try and remove it. Finally, mark the feed and return hoses so you don't put them on backwards and seal them with an m8 bolt to stop crap getting into the lines while working.

Add a little grease in the threads of the plastic lid when you go to do it back up as a gift to your future self, and make sure you put it on evenly/not cross threaded. 

Having said all that, most likely the lid just needs to be either tightened or removed and put back on without being cross threaded...the seal itself is usually pretty good.

[GTSBoy]

Also, the cause of fuel spills and smells from the top of the tank is almost always the rubber hoses that are up there, not the tank seal.

[DraftySquash]

On 19/03/2025 at 11:14 AM, Duncan said:

1. No, as you say you can remove the connectors and fuel lines. Before you do make sure you remove fuel pump fuse and crank the starter a few times to release pressure, and also loosen the fuel cap (just in case the tank is slightly pressurised) as it will pump out the lines otherwise

Awesome!! Yes, I watched a few videos and a few would crank the engine while the pump was unplugged to remove most of the fuel on the lines

 

 

On 19/03/2025 at 11:14 AM, Duncan said:

Also, the plastic nut that holds that seal in place can be really hard to remove

lol.. yeah I have seen/heard that. I do plan to use a trusty screwdriver.

 

On 19/03/2025 at 11:14 AM, Duncan said:

Also the fuel lines can be very sticky on the tank lid fittings

I was going to get this: https://www.supercheapauto.com.au/p/toledo-toledo-fuel-vacuum-hose-disconnect-pliers-301173/670955.html?srsltid=AfmBOopMfURCj-DXVF1BK9Gp08j2KMhHTHXKiNT7axnN94ucNvianAy7

I watched one video where the guy broke the plastic nipple when trying to remove the hose. My luck would highly suggest that will happen to me without a proper tool 🤣

[Murray_Calavera]

29 minutes ago, DraftySquash said:

lol.. yeah I have seen/heard that. I do plan to use a trusty screwdriver.

I would strongly suggest using the correct tool. They are not expensive and make the job much easier and don't damage the lock ring. Google "fuel tank lock ring removal tool" to see what I'm talking about. 

[GTSBoy]

Takes a few minutes to malke one. Wood, or steel, or a wrap strap with some strategically placed solids to provide teh drive onto the ribs.

[Duncan]

1 hour ago, DraftySquash said:

...I was going to get this: https://www.supercheapauto.com.au/p/toledo-toledo-fuel-vacuum-hose-disconnect-pliers-301173/670955.html?srsltid=AfmBOopMfURCj-DXVF1BK9Gp08j2KMhHTHXKiNT7axnN94ucNvianAy7
...

good choice....I have a set of those and use them all the time including on this job. Plus, no-one wants a damaged nipple

[GTSBoy]

2 hours ago, Duncan said:

Plus, no-one wants a damaged nipple

I can direct you to a couple of videos on line where there is evidence to the contrary.

[Kinkstaah]

Supercheap auto sell this:

https://www.supercheapauto.com.au/p/pat-plusquip-fuel-tank-lock-ring-tool---universal-kit/SPO3564082.html

I own this and if you HAVE PATIENCE you can remove it without snapping lines and generally being incredibly angry, then said at doing this job. Sadly I've removed the pump about 75,000 times over the years.

I don't know if you're a large lad or a smaller lad but my advice to you as someone who is 185cm is if you are my height or smaller, is to sit in the boot and take your time.

Yes you can put the seal on. The seal goes over the white thing/lid (you will see how it 'slots' in) then the whole assembly presses into the tank. then you screw the lock ring on. I spent so much time doing things the wrong way by trying to mount the seal into the tank first, then putting the white fuel hat on in the space provided. Put it together first then it'll all go in.

But seriously be careful about removing the hoses AND where the removal tool is moving relative to the plastic pipes coming out of the lid when you've removed it.

IT
IS
BRITTLE

So brittle in fact I have two spare lids, and would recommend buying a spare and having it handy before attempting to do this.

May as well throw https://justjap.com/products/deatschwerks-dw300-fuel-pump-nissan-s13-silvia-r32-r33-r34-skyline-c34-stagea?currency=AUD in the tank as well, as this uses all stock plugs and such. You may need to/strongly recommend you re-use your OEM fuel sock or use the one supplied with a length of hose so it sits at the stock height.

[Milkmun]

Shit job but not hard. I'd use a piece of wood to knock the plastic lid open to avoid damaging it, use a vacuum to clean up the fuel sender lid also so crap doesn't fall in.

I'd probably do pump and filter at the same time since you're already in there, I reused my OEM sock after a quick clean since the one provided wasn't long enough. Could also hardwire your pump if you feel inclined.

[tylink720]

10 hours ago, Kinkstaah said:

So brittle in fact I have two spare lids, and would recommend buying a spare and having it handy before attempting to do this.
 

Wish I had this advice when I did my pump. It went in and out 3 or 4 times, and on the last time it snapped.

[DraftySquash]

On 19/03/2025 at 9:12 PM, Kinkstaah said:

I don't know if you're a large lad

Short and chunky mate! 🤣 Yeah I should be able to sit in the boot without much issue
 

On 19/03/2025 at 9:12 PM, Kinkstaah said:

May as well throw https://justjap.com/products/deatschwerks-dw300-fuel-pump-nissan-s13-silvia-r32-r33-r34-skyline-c34-stagea?currency=AUD in the tank as well, as this uses all stock plugs and such. You may need to/strongly recommend you re-use your OEM fuel sock or use the one supplied with a length of hose so it sits at the stock height.

Thanks @Kinkstaah yeah I'd be really keen to get this as well and do it all the weekend after! I prefer one that won't need me soldering or crimping new plugs 😅

... and I might just look for a spare GTT fuel lid lol

[DraftySquash]

Lol.... Google ads are already on it! 

[GTSBoy]

Ads? Who sees ads?

[DraftySquash]

On 20/03/2025 at 9:47 AM, GTSBoy said:

Ads? Who sees ads?

Really? I see ads for all the JDM parts on the bottom of threads  

[DraftySquash]

New DW300 Fuel pump, new fuel tank lid, new plastic lock all on the way!!!

I'll be on ramen noodles for a week but at least my car will have a fresh fuel pump in over 20 years! Thank you everyone for your input ❤️ 

[GTSBoy]

16 minutes ago, DraftySquash said:

Really? I see ads for all the JDM parts on the bottom of threads  

I have ad blockers and automation breakers (like NoScript) installed on all my browsers on all my devices. I have a PiHole at home and use other forms of DNS blocking to prevent the advertisers, and more importantly, the trackers from google, meta and all those other kunnts from watching what I do.

They learn NOTHING! Or at least, as close to nothing as I can make it. I don't care if google knows that I'm searching for things. But they can get f**ked tracking my every move.

Plus, when surfing donkey porn, the automation breakers help to prevent driveby trojan installers.

[Murray_Calavera]

1 hour ago, DraftySquash said:

I prefer one that won't need me soldering or crimping new plugs

There will be wiring, preferably crimping. The whole "skyline specific fuel pump" marketing that DW uses is a lie. It's just an ordinary fuel pump with all the ordinary bits that come with it. You still need to do all the wiring that you would have had to do otherwise if you bought something like a generic Walbro 525 pump. 

Other things to consider (based on my horrible experience using DW pumps)

* How is the fuel pump sock attached? On my old DW pump there was no locking mechanism, it was an interference fit and after a couple of years of driving, the sock came off. I now have a random fuel sock floating around in my tank =/

* Does the fuel pump have an internal check valve? My old DW pump didn't. Not having one is a pain. Just another thing to buy and faff about installing into your fuel line. I wish it was stated on the product box/online description 'no check valve'. The product description gave no indication if it had or didn't have one. I wouldn't have bought it had I known it didn't have an internal check valve. 

* Consider the depth the factory fuel pump sock reaches in the tank. If you install the DW pump in the stock location and use the baby sized sock supplied, you will find yourself running out of fuel with like 15 litres of fuel still in the tank. +

* Do you have any plans to use e85 in the future? Now is the time to install submergible e85 fuel lines in the tank.  

[GTSBoy]

I thought DW was one of those things that people thought was the bomb ~10 years ago and since learnt not to use their stuff? Because it's not any better than a bunch of other options, and definitely worse than a number of other options.

[Kinkstaah]

The kit from Just Japanese requires no wiring.

The plug on the DW300 will work with an OEM hanger, plug and sock. I have tested this recently within the last couple of months.

Sure, it won't do 500kw+ on E85 on a single pump.. but that's not the use case here, and it wasn't for mine either given I have 0 boost and thus it can flow very happily.

But mainly stock wiring, fuel hat, amp draw concerns being 0 is a major factor.