Fuel smell from under bonnet

[TurboTony]

J-LLO is running better than ever apart from one problem. When driving with the roof off or roof up, window opened I get a strong smell of fuel coming from under the bonnet. It is not all the time, but particularly noticeable light throttle, regular speed driving. I will also get a smell after full throttle acceleration. Impossible to smell when the car is stationary of course. It is not the smell of rich mixture but that of neat fuel. There are no petrol leaks and I have even cleaned the engine to make sure that a weep is not hidden by some crud. The fuel pipe from the pressure regulator can be twisted and I did not know if the union is failing. Here is a photo, with the protective shroud removed:



I would try and replace the pressure regulator but I would probably have to order from the USA.

Any thought where there could be another escape of fumes would be welcome.

[GreenV8S]

Run the pump for a few minutes with the engine cold - you may get a drip you can trace back.

[Fefeu52]

Hard to find, It could be the seal between the regulator and the rail, but it could also be any seal between the rail and one of the 6 injectors. or between the regulator and the fuel return pipe.

Could you attach a child in the engine bay with a light while you go for a test drive

[TurboTony]

I have now tried having the ignition on without the engine running for some time and no weeps, no smell. Ran the engine up to temperature and still no signs. I will have another look tomorrow. I suspect that it is a seal somewhere, although I do not want to strip the plenum and fuel rail unless absolutely necessary. It is a cast rail BTW. I thought about trying a rolling road to see if something could be seen under load. Unless there is someone reasonably local who knows Colognes inside out.

[GreenV8S]

You need to actually run the pump to keep everything pressurised. Just leaving the ignition on won't do it.

[phillpot]

TurboTony said:

The fuel pipe from the pressure regulator can be twisted and I did not know if the union is failing.

That's a "John guest" fitting, only sealed by an O ring so will be free to turn..... but O ring could be old and hardenned? As could be the O ring that seals the regulator to the manifold?

If running the pump while you go for a cuppa and come back with a fag doesn't work how about wrapping some tissue around any suspect areas, go for a little drive (after you've finished your ciggy) and while any fuel leaking will probably have evaporated with all the heat it may have stained the tissue?

Fuel feed and return pipes definitely okay? Proper fuel pipe clips not horrible little "Jubilee" clips?

nice big picture of some pipe clips....................

[TurboTony]

Thanks for the advice everyone. Doh! I should have thought about bridging the relay to keep the pump running. I will have to look in the rats nest to find the relay! Or I could just run a live feed to the pump from the battery?

Mike. The pipe are the original plastic so no hose clips under the bonnet.

[TurboTony]

On reflection, probably not good to have a permanent live feed stuck on the battery when looking for a fuel leak!

[Penelope Stopit]

XXXXXXXXXXXXXXXXXXXXXXI've deleted my post about bridging out the fuel pump relayXXXXXXXXXXXXXXXXXXXXXXXXXXXX

You are not going to be able to safely power anything while there are petrol fumes around the car
The weight of petrol fumes keeps them low, if you were to create an electric spark those fumes will ignite

Don't even think about turning the ignition on or cranking the engine

[TurboTony]

Thanks. Was just about to do it. But how do I work out where the fumes are coming from?

[phillpot]

TurboTony said:

how do I work out where the fumes are coming from?

"Hello, is that David Geralds"? .................



Only you can decide what you feel is safe, or not. From your description there aren't exactly gallons of fuel sloshing around, just some intermittent smells?

From that I'd feel safe dropping a fly lead onto the fuel pump, miles away from the engine, and seeing if there's anything to see around the engine?

You've been driving it like it is for how long and it hasn't blown up!

...... But maybe park it well away from any other cars whilest testing, check house and contents insurance and have 999 on speed dial

[Penelope Stopit]

TurboTony said:

Thanks. Was just about to do it. But how do I work out where the fumes are coming from?

I'm so glad that you got my message before starting

You will need a blower or something to disperse the fumes
Don't go by other posters mentioning you should be ok, you won't be ok, it's a disaster waiting to happen and I have been witness to it happening....very frightening

Perhaps you should speak with a technician and ask what they suggest you do
I can very easily suggest things but won't sleep at night

[phillpot]

Penelope Stopit said:

You will need a blower or something to disperse the fumes

Switch on the cooling fans.


Have the Disaster & Emergency Response Team evacuated the Village yet?

[mk1fan]

Go round to Nigel's to do it

Samy developed a really strong smell of fuel when I was [luckily] driving to the garage for a check up. Turned out to be the vac hose from the distributor to the fuel pressure reg.

Is the carbon canister borked?

[Penelope Stopit]

phillpot said:

Penelope Stopit said:

You will need a blower or something to disperse the fumes

Switch on the cooling fans.


Have the Disaster & Emergency Response Team evacuated the Village yet?

Grow up, it's never too late
This is not a time for attempting to be funny, it's a very dangerous situation

[Penelope Stopit]

TonyTurbo

Have you an air compressor?
You could use a compressor to frequently blow away any petrol fumes

You could give the area a good blow off and then bridge out the relay, then at frequent intervals you could keep blowing it off while you look for a leak

It would be good to have someone at a distance holding a blanket just in case

[phillpot]

Penelope Stopit said:

Grow up, it's never too late

Think I'll leave it a bit longer then ...........................

Penelope Stopit said:

It would be good to have someone at a distance holding a blanket just in case

The last thing you'll be is cold if it goes up in flames?

Edited by phillpot on Thursday 9th May 11:33

[QBee]

Penelope is right.

Back in the day, when my parents were rallying their Cooper S, some bright spark decided to clean up the engine bay of his rally Escort using petrol as a solvent.

He died in the fire he caused.

[TurboTony]

mk1fan said:

Go round to Nigel's to do it

Samy developed a really strong smell of fuel when I was [luckily] driving to the garage for a check up. Turned out to be the vac hose from the distributor to the fuel pressure reg.

Is the carbon canister borked?

The vac hose goes from the reg to the plenum as it is a non cat car. So no carbon canister either. I am going out to get a replacement vacuum hose as this is a good idea. The existing one feels very soft and It may even be collapsing.

[mk1fan]

Samy's hose wasn't sealing on the nipples (calm down Nigel) so were replaced with tighter fitting item (easy) and zip tied.