Hi I have a fuel smell but it’s only when the windows are open both or either. No smell from heater vents, air con not really working but in this weather having to have the windows shut like being in a greenhouse. Where should I start looking, all fuel pipes under bonnet have been changed with new clips, new fuel cap as well.

 

Still got your carbon canister? Checked fuel tank filler pipe and hoses connecting to fuel tank?

27 minutes ago, AndrewG said:

Still got your carbon canister? Checked fuel tank filler pipe and hoses connecting to fuel tank?

Yes still have carbon canister, will check fuel filler pipe. It is a vapour smell as you get filling from the petrol pump.

I’d be working through the fuel pipes one by one Tony, your nose is your best tool here, getting sniffing around! Don’t forget the short one at the front of the rail.

Double check all those fuel pipes under the bonnet including to the fuel pressure regulator, had to fix them multiple times.

Then follow the fuel pipes.

6 hours ago, Joely P said:

I’d be working through the fuel pipes one by one Tony, your nose is your best tool here, getting sniffing around! Don’t forget the short one at the front of the rail.

 

1 hour ago, Dazsw said:

Double check all those fuel pipes under the bonnet including to the fuel pressure regulator, had to fix them multiple times.

Then follow the fuel pipes.

We had a good sniff under bonnet, had the car on ramps at the back, no luck looked at top of fuel pump rubber looks old so will change them. The only detectable smell was from the exhaust, they are black inside but do smell of petrol. 

1 hour ago, Bones28 said:

The only detectable smell was from the exhaust, they are black inside but do smell of petrol. 

You might want to check your fuel damper:

http://www.twinturbo.net/nissan/300zx/forums/general/view/2610744/Here-is-how-it-works.html

Edited June 15, 20205 yr by AndrewG

I’ve just had this issue for the last week and kept thinking I need to check it out. Good thing I came across this thread as it prompted me to check. After the car had been left to sit overnight, upon cold start this morning I opened the bonnet to check for leaks, and noticed fuel was very slightly leaking out the hose connecting to the fuel filter input side (pic below). Might replace the hose anyway as it has a couple chips at the end.

I went for a short drive and when I got home I opened the bonnet and all the fuel leakage had evaporated, because of the engine heat obviously. If I had looked at the engine after it was hot only and not before when it was cold, then I wouldn’t have known where it was coming from, as the leakage stains are so faint, I had my face right up close to be able to see the streaks.

So what I’m getting at is, turn engine on when it’s cold and leave for a couple minutes whilst monitoring engine. You might see the fuel seeping out of the offending area.

I read up on a random zed thread about fuel system leaks and that the screw clamps can get loose when going through the winter summer temp changes so they need tightening every now and then. Just tightened it up, started car and revved it for a while and now bone dry.


Sent from my iPhone using Tapatalk

Glad it helped, I recently had the engine out and replaced all fuel pipes with later type spring clips.

New Nissan fuel regulator and dampener but still could be faulty, will check.

For those using old style screw clamps for their fuel lines - Nissan fixed the fuel clamp problem later in the Z32 production

cycle with spring clips (part # 16439-16E0A) which allow for the contraction of the pipes with age.

Edited June 16, 20205 yr by AndrewG

43 minutes ago, naz27 said:

I’ve just had this issue for the last week and kept thinking I need to check it out. Good thing I came across this thread as it prompted me to check. After the car had been left to sit overnight, upon cold start this morning I opened the bonnet to check for leaks, and noticed fuel was very slightly leaking out the hose connecting to the fuel filter input side (pic below). Might replace the hose anyway as it has a couple chips at the end.

I went for a short drive and when I got home I opened the bonnet and all the fuel leakage had evaporated, because of the engine heat obviously. If I had looked at the engine after it was hot only and not before when it was cold, then I wouldn’t have known where it was coming from, as the leakage stains are so faint, I had my face right up close to be able to see the streaks.

So what I’m getting at is, turn engine on when it’s cold and leave for a couple minutes whilst monitoring engine. You might see the fuel seeping out of the offending area.

I read up on a random zed thread about fuel system leaks and that the screw clamps can get loose when going through the winter summer temp changes so they need tightening every now and then. Just tightened it up, started car and revved it for a while and now bone dry.


Sent from my iPhone using Tapatalk

Had to tighten the clips once a year ?

For those using old style screw clamps for their fuel lines - Nissan fixed the fuel clamp problem later in the Z32 production
cycle with spring clips (part # 16439-16E0A) which allow for the contraction of the pipes with age.

Great thanks for this. Will add to my next CZP order.


Sent from my iPhone using Tapatalk

Had to tighten the clips once a year [emoji846]

Yeah makes sense now after reading that thread. Will go around all of them and tighten.


Sent from my iPhone using Tapatalk

18 hours ago, naz27 said:

Yeah makes sense now after reading that thread. Will go around all of them and tighten.


Sent from my iPhone using Tapatalk

I was looking at getting the newer style ones as mentioned above, but then got the Skyline and it was sold instead, they are cheap so worth getting and changing for sure.

If you do replace the old style clamps with the new spring clamps it is sensible to replace the hoses at the

same time. You can buy a 2.2m (7ft) Nissan fuel hose and cut to the individual lengths required.

https://conceptzperformance.com/nissan-infiniti-nissan-oem-high-pressure-fuel-hose-kit-7ft-516-8mm-a6d40-n7686-universal_p_716.php

 

46 minutes ago, AndrewG said:

If you do replace the old style clamps with the new spring clamps it is sensible to replace the hoses at the

same time. You can buy a 2.2m (7ft) Nissan fuel hose and cut to the individual lengths required.

https://conceptzperformance.com/nissan-infiniti-nissan-oem-high-pressure-fuel-hose-kit-7ft-516-8mm-a6d40-n7686-universal_p_716.php

 

That’s what I did

I was looking at getting the newer style ones as mentioned above, but then got the Skyline and it was sold instead, they are cheap so worth getting and changing for sure.

Yeah these cars are always ongoing to do lists hey. Good thing you told me they need checking every year cos about half the screws weren’t tight. Instantly noticed when we went for a long drive last night that the fuel smell had gone so happy days [emoji1417]


Sent from my iPhone using Tapatalk

If you do replace the old style clamps with the new spring clamps it is sensible to replace the hoses at the
same time. You can buy a 2.2m (7ft) Nissan fuel hose and cut to the individual lengths required.
https://conceptzperformance.com/nissan-infiniti-nissan-oem-high-pressure-fuel-hose-kit-7ft-516-8mm-a6d40-n7686-universal_p_716.php
 

Thanks for the advice Andrew, it’s appreciated [emoji1417] I’ve got in mind to do this, change the filter and repaint the slightly rusty filter clamp whilst I’m at it.


Sent from my iPhone using Tapatalk

Or you can buy Gates Barricade for a 3rd of the price and get some Mikalor 14mm Spring clamp Clips from Ebay like i do.

Or you can buy Gates Barricade for a 3rd of the price and get some Mikalor 14mm Spring clamp Clips from Ebay like i do.

If it’s good enough for you, it’s good enough for me! Thanks a lot for the info [emoji1417]


Sent from my iPhone using Tapatalk

I replaced the hoses when I had the plenum off, some years ago. New clamps. No problems. Do it once, do it right, it’s fuel. 
Before this is used to leak in the cold, I’d tighten and it would be ok, then I’d need to retighten a while later. 

Does anyone know how much rubber pipe is used between the fuel tank and the hard lines under the car and why it is not mentioned with fuel line replacement. 
Thanks ? 

 

 

7 minutes ago, Bones28 said:

Does anyone know how much rubber pipe is used between the fuel tank and the hard lines under the car and why it is not mentioned with fuel line replacement.

Can't answer the first part but I would suggest that they are not subjected to the hot heat cycles of the engine bay which harden rubber pipes

over time. Along with plastic connectors and engine harnesses.

Edited June 18, 20205 yr by AndrewG

6 minutes ago, AndrewG said:

Can't answer the first part but I would suggest that they are not subjected to the hot heat cycles of the engine bay which harden rubber pipes

over time. Along with plastic connectors and engine harnesses.

Very true how long do you think rubber can last, supposed it depends on how a car was stored, used and what part of the world for imports.

Hi today with the help of my brother we managed to take the fuel vapour vent line check valve out, it was hidden above the rear Hicas lines, black round Unit, bit rusty up there but that will be done another time.

 

We tested it and air passed through it both ways very easily, so we cut the end off and expanded the spring inside, glued it back together 

Tested it again and it worked would only pass air one way, fitted it back and started the car, revs went to 500 then back to 850 but a bit rough also stalled when I stopped reversing, tomorrow will take it for a drive then plug the Conzult in.

Being a NLA part I will have to find a different one from another car.