Strong Smell Of Petrol When Driving

[kehoeautomotive]

I have spent over a year trying to eradicate a fuel smell. The problem is pressing as the car lives in an integral garage next to the kitchen and food is beginning to taste of petrol ! We replaced the right side fuel rail last week to no avail ( The service port was leaking so the job was worth doing, but the smell remains. We replaced the balance pipe between the tanks ( two rubber bits and a steel tube) But again, no luck. The fuel system holds pressure well and the car has been fitted with an EGR valve.

There is no doubt at all that the smell is " loudest" in the viscinity of the metal part of the lower balance pipe with the smell then travelling up the front of the engine and also to the left rear wheelarch. Bizarrely, it appears in the front wheelarches as well ! This supports the idea that the smell starts somewhere just in front of the crankshaft and then convects up the front of the engine and along the inside of the backbone. The valley between the cylinders (It's a V8) has no smell at all and nor do the injector rails or service port. There is no smell behind the trim panels which sit above the tanks.

Question is: If the smell is comming (or seeming to be coming) from the central pipe of the balancing hose and pipe, but this has been replaced in its entirety with new jubilee clips etc. and no sign of any petrol stains: Where on Earth is the leak !!??

Thanks for any ideas. Meanwhile, I will investigate the upper balance pipe. Where exactly does it lie, height-wise ??

Thanks again

 

 

I would suggest a evaporative system smoke test. The mechanics at my work (I'm not a mechanic, I just own a tire store) use a smoke machine to fill the fuel system with smoke. Then they close the purge valve (Lotus does not have one but you could pinch off lines with a pair of needle nose pliers) and then you should be able to SEE the leak, not just smell it. I was planning to do this on my car soon actually.

[jonwat]

The valley between the cylinders (It's a V8) has no smell at all and nor do the injector rails or service port. There is no smell behind the trim panels which sit above the tanks.

 

In that case, you'd probably get a better response if you post the question in the V8 model forum. 

[top-plumber]

It's not a balance pipe it's a vent pipe. It allows any pressure build up in the tanks to vent to atmosphere via a charcoal canister that removes the smells and also collects small amounts of fuel and purges it's self back into the system. If the vent pipe is perished( highly likely) then it needs replacing. It runs above the rear window in the track above the glass and down each side to the filler neck of each filler cap.

Wayne

[Vanya]

In that case, you'd probably get a better response if you post the question in the V8 model forum. 

Hahahha that place is dead man. 4-pot forums is where it's at.

[Yellow Peril]

I was worried the tank might be leaking but when I removed the side panel I found this:

http://www.thelotusforums.com/forums/gallery/image/4130-breather1/

 

So, 3 hours later, breather pipe was replaced and the smell has gone - yippee!

 

One point though - I used the LEW guide and bought 10mm internal diameter pipe. It was a b*tch to get onto the fuel pipes so I retained the elbow and short bit of hose because they were fine and that went back on easily. I think a 12mm pipe would have been better.

[plumdeplakmuis]

Same bad smell on my 1998 GT3, I can't find the hose around the rear window as in the LEW guide though.

Can it be the routing was changed for the 1998 model?

[Sparky]

It's there, but a much thicker black hose. On top of the right tank, in the forward outer corner, there's a t-junction that commonly fails - try that.

[plumdeplakmuis]

Check, located it.

yes the t-junction has failed, yellow hose broke of the black hose piece.

And looking further, same issue on both sides of roll over valve.

 

I think I will go for a single piece hose from the T-junction to roll over valve.

And from roll over valve to charcoal canister, 

[set]

I replaced the balance pipe some years ago (with enormous help from Steve Smith) but the smell of fuel has returned so I had another look today and found two loose pieces of the old pipe behind the trim on the driver's side.  There is a very short section of pipe (about 3 inches) attached to the second flange on the fuel filler pipe, but it seems to have been cut at an angle and matches the end of one of the loose pieces.  What should that second pipe be attached too? I assume it should be connected to something - any guidance appreciated.

I've looked at the LEW guide to the breather pipe replacement, but it isn't clear where that pipe goes.

[Escape]

It sounds like that's the pipe from the fuel tank to the charcoal canister (via the roll over valve that's tucked away in the rear pillar).

[set]

Thanks Filip - I did wonder, but couldn't see the rollover valve either (perhaps it is missing?). I'll try and post a photo next time I open it up again.  It still seems to run OK at the moment and wasn't too smelly on a short run this morning.

[fjmuurling]

Just become a FFM (full forum member) and ten you can download the parts manual, which has excellent drawings of the fuel system (and much more). The biggest advantage is that it will also support TLF.