Chimaera Fuel smell

[keeling54]

So I've had my Chim for around a month now and it has a niggly fuel smell in the cabin. Strange thing is it's only noticeable with the roof off or the windows down when I'm driving along, it doesn't smell when stationary and idling.

I've had it on the ramps and checked the pipework from tank to engine and back again and their are no leaks. The smell is strongest in the boot after a run.

I suspect I don't have a leak but their are fumes escaping from some where. Any suggestions where to start looking before I pull the tank and start there.

I've ordered up a fuel cap and sender gasket, I'll do those first because they are easy.

[jojackson4]

Roll over valve

[bobfather]

Have you checked the boot for petrol smell? There are plenty of passageways for vapour to be drawn from the boot into the cabin area. Also, the flexible fuel hoses to the drivers side and behind the plenum are renowned for leaking

[keeling54]

Yes, the smell is definitely coming from the boot and getting into the cabin, no smell at all under the bonnet.

I've pulled all of the carpets and none of them are wet, no patches of fuel either in the boot, while it was on the ramps I check the short length of flexi pipe from the tank and it appeared fine.

I can't see down the back of the tank so may need to pull it put to see if there is anything happening behind it.

Edited by keeling54 on Saturday 14th May 21:04

[keeling54]

jojackson4 said:

Roll over valve

Is that the small plastic thing sitting behind the tank just below the filler pipe.?

[bobfather]

keeling54 said:

Is that the small plastic thing sitting behind the tank just below the filler pipe.?

Yes

[bobfather]

You need to access the rear of the tank, any movement of the tank will put stress on the bottom hose which is very short. My method of doing this is to release the large filler flexi and syphon out the fuel, there's a low point at that end of the tank so syphoning gets almost everything out. Once empty, disconnect the bottom hose close to the tank so that moving the tank won't stress the bottom hose. Unbolt the two top strap nuts and lean the tank so that you can view the rear. This will give you access to several hidden hoses including the return hose connected behind the sender. The original hoses are not ethanol resistant so I would suggest that you take the opportunity to swap out all the flexi hoses for R9 or better, they may look okay but you'll find that they will be getting rigid and may be starting to become porous

[kris450]

I had this and the hose at the bottom of the tank had split slightly. Made the boot stink. Trouble is once it was replaced the boot still stank and continues to do so. And thats about 6 years on... Once fuel is in the carpet its a pain to get out. Tried fabreeze etc, nothings touched it. Not the end of the world.

Or as you have perhaps sussed, try replacing the fuel filler cap. Might be leaking fumes maybe.

[Belle427]

May be worth replacing the hoses including the fuel return which gets overlooked because it’s behind the tank.
Not a big job to pull the tank forward, a lot easier if it’s fairly empty but this is easy to achieve in a V8 !

[bobfather]

I've just completed this job on ramps in a very narrow garage, not difficult but access to the fuel filter is a bit of a fiddle, best to leave a day for this task.

See here for hose sizes and supplier

https://www.pistonheads.com/gassing/topic.asp?h=0&...

Use only stainless steel hose clips preferably something better than Jubilee clips

This was my reason, fuel smell ended up being a pinhole in the tank which I patched

https://www.pistonheads.com/gassing/topic.asp?h=0&...

Mine is unusual as it has a steel tank with bottom hose accessible from a grommet in the boot floor, most tanks have bottom hose access from the wheelarch

[keeling54]

Thanks for all of the replies.

Looking through the old receipts I got with the car it appears that the hose were all replaced a year or so ago by Taylor TVR, I messaged the previous owner and she said it had started to smell of fuel in the boot straight after the hoses were replaced, they took it back and Taylors sorted it. I may give them a call on Monday to see if they remember the car and ask them what they did.

I've pulled all of the carpet and the carpet doesn't smell and the smell disappears when the car is parked up and the boot left open.

As I bought the car as a mini project and I left myself some budget for odds and sods, I'll pull the tanks a described above and give everything the once over.

[keeling54]

I've solved the fuel smell, I took the tank out and found a bodged repair in one of the indentations on the back of the tank, it appears the tank has at some point rubbed up against one of the body securing bolts and worn through, the bodger has then applied a load of black mastic over top and put the tank back.

The previous owner had the car looked after but a so called 'TVR specialist', looking through the bunch of receipts I got with the car, all of the hoses were replaced with R9 last year, I can't believe they replaced the hoses and then bodged or worse ignored a badly repaired tank and just refitted it.

[url]


|https://thumbsnap.com/WhMof1NR[/url]

[bobfather]

You can get patch plates for alloy tanks. Mine had a very similar leak but my tank is steel so I was able to sweat a plate over it with boiler makers solder

[keeling54]

bobfather said:

You can get patch plates for alloy tanks. Mine had a very similar leak but my tank is steel so I was able to sweat a plate over it with boiler makers solder

That's my next dilemma, how do I patch it.

[bobfather]

keeling54 said:

That's my next dilemma, how do I patch it.

JB Weld, it's a resin sealant. People often use it to bond an alloy patch on. Your problem will be proximity to whatever caused the damage. Perhaps you could glue a rubber backing on the tank to protect it. You'd loose some boot depth but I doubt it would be too noticeable

[Belle427]

If it were me I'd look to get it repaired properly or sadly get another tank.
Finding someone to repair is the hardest part.

[sixor8]

I used something called 'QuikSteel' on my old Triumph Toledo; I mention this because it is a metal tank, and OE replacements are not available. All the second hand ones are usually rusty and bespoke replacements are £500 ish. It is also actually inside the car (in the boot) but the base had been allowed to sit in water that had leaked in.

It had some rusty leaking areas and small holes but sealed it up. I also put a POR-15 liquid tank liner inside and it's been fine for over 6 months so far, cross fingers. By the look of that leak, is it possible to only buy half a tank full or so at a time, even after any repair? It may reduce the chance of a leak. 2 part epoxy resin may be sufficient too but I'm unsure if all such products are fuel resistant.

Edited by sixor8 on Sunday 12th June 09:11

[lancepar]

The bolts for the body to chassis behind the tank should have a dome head, are yours?

[Steve_D]

That PU sealant may not be what you think.
From the factory the upper two chassis bolts were dome head and had a mound of sealant applied over the top.
What you have found may well be that.

If the previous garage had replaced hoses there would be no need for them to remove the tank.

The tank can simply be ali welded but would need to be done with the tank full of water for safety reasons.
After the repair glue a ring of firm rubber araound the fix so the bot does not rub again.

Steve

[keeling54]

lancepar said:

The bolts for the body to chassis behind the tank should have a dome head, are yours?

Yes, both are domed. The one near the hole a piece of rubber stuck over it.