| Home  Blogs Help Search Login Register  
« previous next »
Pages: [1] Print
Author Topic: Smell of petrol  (Read 16084 times)
Tricky Dicky
Jr. Member
**
Posts: 32


« on: July 24, 2007, 05:43:04 pm »

I have twin weber carbs fitted to the blue beast, whilst at the MOT station the tester and friends could smell petrol, however after a considerable amount of searching and sniffing could not find where the smell was coming from.
No leaks or sign of any leaks.
Any suggestions I have got used to the smell it has always been there for the last 3 years.
Logged
krede
YaBB God
*****
Posts: 1172



« Reply #1 on: July 24, 2007, 05:54:54 pm »

I run a similar set up twin Dellorto 40mms and my car smell A LOT! of "eu de gas-oline" (Much better then any other  cologne Ill tell you  Grin )
I speculate that some fuel in the carb bowls that gets heated up and evaporates after the car has stopped.. as there is no sigh of leaks anywhere.
« Last Edit: July 24, 2007, 05:56:44 pm by krede » Logged
Tricky Dicky
Jr. Member
**
Posts: 32


« Reply #2 on: July 24, 2007, 06:14:54 pm »

Thats the answer I was hoping for as it only ever seems to be at initial start up.
I prefer the smell of Napalm in the morning! a famous line from one of the best films I have ever seen well in my opinion but what was the film?
No prizes for guessing because of the rules governing competitions over here in the UK.
Richard
Logged
krede
YaBB God
*****
Posts: 1172



« Reply #3 on: July 24, 2007, 06:19:19 pm »

http://www.youtube.com/watch?v=pwqdBkaWsTA
Apocalypse now!!.... great film... but my god the directors cut is far out!
« Last Edit: July 24, 2007, 06:22:37 pm by krede » Logged
Anders Dinsen
Administrator
YaBB God
*****
Posts: 3186



WWW
« Reply #4 on: July 24, 2007, 07:53:09 pm »

I have twin weber carbs fitted to the blue beast, whilst at the MOT station the tester and friends could smell petrol, however after a considerable amount of searching and sniffing could not find where the smell was coming from.
No leaks or sign of any leaks.
Any suggestions I have got used to the smell it has always been there for the last 3 years.

The problem with petrol fumes is that they go away in seconds, so you won't have time to find where it comes from.

But fuel leaks are no joke, so I suggest you go through the system. First to check is the fuel pump on the right side of the engine, which has caused a few Murena engine fires since if it leaks it does so on the exhaust manifold.

But if you are running pancake type filters and not an airbox, you will probably never be able to get rid of the smell, after all the float chamber of the carburettors is ventilated throgh the inlet, I think.

- Anders
Logged

1982 Talbot Matra Murena 2.2 prep 142
2017 BMW i3 "Charged Professional" 94Ah

Used to own:
2001 Renault Matra Grand Espace "The Race" V6 24v
1997 Renault Matra Espace 2.0 8V
1987 Renault Matra Espace J11 2.2
krede
YaBB God
*****
Posts: 1172



« Reply #5 on: July 24, 2007, 08:32:41 pm »

-sniff-  ... -snif snif- .... and its the good stuff... 98 octane ... not the usual 95 unleaded...  Grin

But on the serious side... I run an electric pump situated in the left hand side of the engine compartment ... all the fuel lines are braided and in plain view.. any leak should be easy to spot..



.. and yes... Gasoline is a serious fire hazard.. .. but sadly its often treated much too carelessly... more then once I have had to ask people not to smoke while they were filling up their cars!!! ...its just unbelievable!! 
Logged
macaroni
YaBB God
*****
Posts: 533


Murena and Multipla - I like it 3 abreast!


« Reply #6 on: July 24, 2007, 08:47:53 pm »

2nd reference to Apocalypse Now in the Murena section - spooky!

I have twin Dellortos with Pancake air filters and always smell petrol. It is far more pleasant (for me, if not the environment) than the rotten egg smell from modern Catalytic converter equipped cars.

I love your engine bay Krede, I wish mine was as tidy.

From where do you take the power for the electric fuel pump?
Logged
krede
YaBB God
*****
Posts: 1172



« Reply #7 on: July 24, 2007, 09:26:19 pm »

The pump was already installed when I bought the car.
As far as i can tell from the service log , It was fitted some years back following an engine fire caused by..... yup.... a leaking standard fuel pump .

The pump is fed by a relay that takes its current from the b+ on the starter motor, and is activated as far as i can tell , along with the ignition (15).. a very straight forward set up, but not the safest in a crash.. as it will keep pumping fuel as long as the the ignition is on.
I believe Anders has written a page about wiring up electric fuel pumps?

Anyway. my engine bay will not look like this for much longer, as I have collected these parts during the last couple of months :



45mm throttle bodies and assorted goodies  Grin
At first my plan was to have an inlet manifold made by a "mate of a mate" but he took too long, and the intake "roar" would have been lost.. and i really love that sound.
So I ended up with buying these in stead ... .. It should improve the fuel consumption quite a bit (my car has AT NO POINT done more then 9km/l.. and usually does about 7-8).
I reckon the gasoline smell will disappear as well.. and as a final bonus, the TB's are shorter(8cm in total) then the carbs allowing for deeper ari filters, and even some (very short) air horns/trumpets.
I don't expect much with regards to power.. thought the more accurate mixture will probably yield a few hp, for as Roy has said.. very few have gotten the twin carbs to run perfectly on murenas .. and I know ,as does any body that has ever heard my car approaching (and that would be everybody in the general area) that my car is running.... slightly rich   Grin
In fact one could speculate , that if you took a really really modest car, like, say, a petrol Lupo, or Yaris, and drove it right behind the exhaust of my greedy eel , the small critter would be able to run on what my car breathes out.  Grin Grin Grin 

     
« Last Edit: July 24, 2007, 09:43:48 pm by krede » Logged
Anders Dinsen
Administrator
YaBB God
*****
Posts: 3186



WWW
« Reply #8 on: July 24, 2007, 11:11:37 pm »

I believe Anders has written a page about wiring up electric fuel pumps?

Indeed I have, it's here: http://dinsen.net/murena/electrics/fuelpump.

Electrical fuel pumps normally don't draw more than a few ampere, so it does not really need a relay. It is okay to run it off the ignition, which can be taken from the + side of the ignition coil. The simples cut-off solution involves an oil pressure switch, but one advantage of the electrical fuel pump is that it can prime the system and fill the float chamber before starting the car. If you want this feature, you can't rely on the pump running only when there is oil pressure in the engine.

In some cases (depending on the carburettor) priming can make cold starting easier.

So another electrically simple solution with this benefit preserved would be to power the pump through an inertia switch as found on cars from the 90's. Late 90's and post 2000 cars all has airbags as standard equipment, and then the manufacturers started fitting the collision cut off switch in the air bag module. The inertia switch is a very simple device that cuts a circuit if subjected to a large acceleration in the horisontal plane (in the area of 5-10 G, I think).

The switch can be reset by pressing it down.

I have to admit that I have still not implemented any safety cut off feature on my pump, but I'm working on it... Wink

But my pump has been working flawlessly for 6 months or so, and the pump I chose (Lennart, do you remember the very "scientific" criteria we used?) has the advantage that it doesn't need a fuel pressure regulator, but pumps up to a calibrated 0.25 bar Undecided.

- Anders
Logged

1982 Talbot Matra Murena 2.2 prep 142
2017 BMW i3 "Charged Professional" 94Ah

Used to own:
2001 Renault Matra Grand Espace "The Race" V6 24v
1997 Renault Matra Espace 2.0 8V
1987 Renault Matra Espace J11 2.2
Lennart Sorth
Administrator
YaBB God
*****
Posts: 831



WWW
« Reply #9 on: July 24, 2007, 11:31:20 pm »

petrol Lupo, or Yaris, and drove it right behind the exhaust of my greedy eel , the small critter would be able to run on what my car breathes out.  Grin Grin Grin 

LOL - I can see Krede's Murena followed by a hord of hungry Smarts (It would have to be Brabus's though)  :-)

/Lennart
Logged

Lennart.Sorth@matrasport.dk
Murena 1983 1.9i silver // Honda e '20 Charge Yellow  // VW Polo '22 1.0 tsi silver//
Lennart Sorth
Administrator
YaBB God
*****
Posts: 831



WWW
« Reply #10 on: July 24, 2007, 11:47:17 pm »

(Lennart, do you remember the very "scientific" criteria we used?)

indeed ahem, - but size matters, as Helene Mahieu said. :-)
(for those who don't know/remember - she was in the Renault Clio adds where the catch phrase was "Size Matters" )

But I'm frankly amazed that you got it working, as I remember being a bit concerned about pressure and fuel-return ?

/Lennart
Logged

Lennart.Sorth@matrasport.dk
Murena 1983 1.9i silver // Honda e '20 Charge Yellow  // VW Polo '22 1.0 tsi silver//
krede
YaBB God
*****
Posts: 1172



« Reply #11 on: July 25, 2007, 04:31:41 pm »

Quote
but size matters,

DAMN!!
Logged
roy4matra
YaBB God
*****
Posts: 1199



« Reply #12 on: July 25, 2007, 09:52:26 pm »

I have twin weber carbs fitted to the blue beast, whilst at the MOT station the tester and friends could smell petrol, however after a considerable amount of searching and sniffing could not find where the smell was coming from.
No leaks or sign of any leaks.
Any suggestions I have got used to the smell it has always been there for the last 3 years.

Well it might be normal vapour.  One consequence of all new cars being injection and having to meet emission regulations that also include fuel venting and vapour, is that most modern cars no longer have a petrol smell which was more common when carbs. ruled. :-)  Consequently many modern mechanics are simply unused to having any smell unless there is a fault.

However, since you state it has been there for the last three years, it could be normal for your car.  That is not to say it is correct though.  You may have too much vapour, but no leak.  Or you may have a very minor leak.  Although leaks can be dangerous, heavy vapour can be worse.  It is the vapour that tends to extremely flamable, whilst the liquid is too rich to ignite (although there will be vapour coming off the liquid so it is obviously dangerous too) so you need to make sure everything really is O.K.

If you religiously log all your fuel usage, then it has additional benefits.  1) you can work out your overall fuel consumption accurately over a period of time; 2) you get to be able to monitor the actual amount in the tank more accurately (I can usually tell to the litre just how much my tank will take to fill; or just how much I have left in the tank - useful when you need to know if it will reach the next fuel station!) and 3) if the fuel consumption suddenly increases it will alert you to something being wrong - possibly a leak.

Roy
Logged

Pages: [1] Print 
« previous next »
Jump to: