Heated nearside fuel Tank! 400/450SE

[The Colonel]

Got the wedge up on axle stands whilst de-rusting chassis and doing painting, so I have had a good look at all the underneath bits.

Noticed that the exhaust pipe that is under the tank - runs from 3 bolt flange thingy towards rear with only 5 mm clearance with tank at closest point.

Nowing how bl*ody hot the tail pipe gets methinks I will use heatwrap on the pipe locally.

Anyone else concerned about this on their wedge?

[stainless_steve]

It's been ok for 14 years so i think you will be ok
Heatwrap does sound a great idea though
Mine is not that near the petrol tank though.

[The Colonel]

I was trying to get to sleep the other night, - and what was going through my mind was the thought of the petrol bubbling up like water in a kettle and venting off into the atmosphere faster than the engine drinking the stuff !!

- no that's impossible isn't it?

[grahamw48]

Maybe it is possible.

You reminded me of an occasion years ago, when shortly after having bought a series 4 Lotus 7, I had to call the blinking fire brigade out to it!

Turned out the exhaust had been heating up the fuel tank to the point where it was venting out of the cap like a kettle !!!

At the time it was pretty scary !

[mikeb]

Ha!!! I was thinking exactly the same thing when I had a look underneath.

I reckon that it would be ok when driving as the heat gets washed away but sitting in traffic on a hot day

I was gonna get a steel plate made up and mount it over the exhaust to soak some of the heat away.

The next idea was to get some exhaust wrap and wrap that particular bit of the exhaust.

It's obviously been ok for alll these years but still dosen't make for a good nights sleep if you start pondering the issue.

Will probably go for the wrap should do the job nicely. My exhaust is stainless as well so shouldn't cause any corrosion issues.

I am also gonna replace all of the petrol pipe for braided stuff, Tim at ACT is looking into getting hold of some good stuff as we speak.

MikeB

[grahamw48]

Perhaps a wise move, as after all, burnt-out wrecks at the roadside are not that uncommon.

Oh, and I'm not talking about myself walking the dog.

[Trooper2]

The Colonel said:

I was trying to get to sleep the other night, - and what was going through my mind was the thought of the petrol bubbling up like water in a kettle and venting off into the atmosphere faster than the engine drinking the stuff !! - no that's impossible isn't it?

That's why cars have evaporative emissions systems on them, to keep the hydrocarbon vapors escaping to the atmosphere and burning them in the engine at the appropriate time.

[shpub]

There should be a heat shield and the pipe covered in heat shield material.

If not replace immediately.

[paul gotts]

During a summer holiday in France a few years ago, I filled the 350 tanks, and parked up not far away to check maps etc. Two minutes later, even though the engine was off, fuel started gushing from the overflow just behind the n/s rear wheel, caused by the heat soak. The only solution was for me to drive a couple of miles down the road, and do some laps of the public road portion of the circuit at Clermont Ferrand. All my friends could hear was this V8 howling away in the valley below them.Great way to use some fuel.

Since then, I have stuck some heat insulating/reflective material to the underside of the n/s tank on the 400 and not had a repeat of the problem.

[FrenchTVR]

paul gotts said:

During a summer holiday in France a few years ago, I filled the 350 tanks, and parked up not far away to check maps etc. Two minutes later, even though the engine was off, fuel started gushing from the overflow just behind the n/s rear wheel, caused by the heat soak.

This happens on my 350 quite a bit, may have to fit some reflective heat shielding while it's off the road.

[h2dca]

I noticed a similar thing with the large hose that joins the two tanks on my 400SE. The exhaust is rather close to this and the old hose did show signs of aging due to heat around that specific area, anyway I have replaced the hose with a wire-armed hose and wrapped the hose in reflective tape.

[boltontvr]

FrenchTVR said:

paul gotts said: During a summer holiday in France a few years ago, I filled the 350 tanks, and parked up not far away to check maps etc. Two minutes later, even though the engine was off, fuel started gushing from the overflow just behind the n/s rear wheel, caused by the heat soak. This happens on my 350 quite a bit, may have to fit some reflective heat shielding while it's off the road.

This happened to me once, on the day that I bought the car. I nearly messed my trousers when I saw all this petrol gushing out over the exhaust. It had taken me seventeen years to get the car, and I thought it was going to go up in flames after a few hours of ownership. Fortunately it hasn't happened since, but I also don't leave the car idling whilst parked on an incline either.

[dukeenfield]

The vent pipe at top of my n/s tank has been blocked off ,does this matter,is anybody else's car like this.

[SEvans]

Mine was like this but it is a Tasmin 200 so not sure if it's normal on a 350.