Just recently I have noticed diesel has leaked out of the filler cap/overflow after I have filled my 2009 VRS 2.0 CR. Estate. I always fill to the second click of the pump nozzle.

This can only happen when cornering as It must be what is left in the filler neck, has anyone else noticed this happening?

I know it cleans up easily enough but as I ride a motorbike as well I usually curse all other road users that spill fuel on the road its bloody dangerous I now from experience :'( .

Is this just a trait of the estate car or do they all do it? think I will just fill to one click in future.

It has only started happening recently as I always fill the car up and have not noticed this before.

Tony.

Just recently I have noticed diesel has leaked out of the filler cap/overflow after I have filled my 2009 VRS 2.0 CR. Estate. I always fill to the second click of the pump nozzle.

This can only happen when cornering as It must be what is left in the filler neck, has anyone else noticed this happening?

I know it cleans up easily enough but as I ride a motorbike as well I usually curse all other road users that spill fuel on the road its bloody dangerous I now from experience :'( .

Is this just a trait of the estate car or do they all do it? think I will just fill to one click in future.

It has only started happening recently as I always fill the car up and have not noticed this before.

Tony.

I have noticed my Octy is very sensitive to overfilling. When first purchased I was keen to check mpg by brimming the tank but soon learnt to stop filling when the pump clicked off. I would suggest the second click could be click too far.

Velocette

Have to say I've filled the car until I can see the fuel in the filler opening and not had it leak out.

Your diesel fuel tank has a build-in heater (for colder days, but actually always working), so if you overfill after the first click, the diesel might overflow since it will be expanding due to being heated (in combination with taking sharp corners and/or bumps in the road).

Your diesel fuel tank has a build-in heater (for colder days, but actually always working), so if you overfill after the first click, the diesel might overflow since it will be expanding due to being heated (in combination with taking sharp corners and/or bumps in the road).

Where did you hear that?

There is a cooler under the car so that hot fuel coming back is cooled before it hits the plastic fuel tank and I was under the impression that any heating of the fuel only happens due to warm fuel going back into the tank after non injection into the engine.

Never had this problem and often brim it, also, hot fuel comes back into the tank from where? sounds very dodgy to me.

Have to say I've filled the car until I can see the fuel in the filler opening and not had it leak out.

Same with mine...

Where did you hear that?

There is a cooler under the car so that hot fuel coming back is cooled before it hits the plastic fuel tank and I was under the impression that any heating of the fuel only happens due to warm fuel going back into the tank after non injection into the engine.

User manual of my previous car (VW Golf III TDi) contains a specific warning that the diesel tank contains a buildin heater (for colder days) and overflow will likely happen after topping up. In the same manuel it is stated that it is not good to run empty on your tank since the heater will get exposed and damaged.

I assume that the heater is present on all VAG cars with an diesel tank.

I do not know how the heater exactly works, but the overflow will happen due to fuel expanding with raising temperature. Out of the pump fuel is about 7 C degrees, inside the fuel tank it might raise to about 25 C degrees (as I remember from the manual, but I sold my car incl the manual).

Never had this problem and often brim it, also, hot fuel comes back into the tank from where? sounds very dodgy to me.

The car injects fuel and fuel left in the rail/lines that doesn't get injected is returned and can end up back in the tank.

YOu can see the return line on the diagram below.

User manual of my previous car (VW Golf III TDi) contains a specific warning that the diesel tank contains a buildin heater (for colder days) and overflow will likely happen after topping up. In the same manuel it is stated that it is not good to run empty on your tank since the heater will get exposed and damaged.

I assume that the heater is present on all VAG cars with an diesel tank.

I do not know how the heater exactly works, but the overflow will happen due to fuel expanding with raising temperature. Out of the pump fuel is about 7 C degrees, inside the fuel tank it might raise to about 25 C degrees (as I remember from the manual, but I sold my car incl the manual).

Ahh I wonder if you have mis-remembered that?

The Golf III might have had a fuel heater, but I suspect that it would be an (optional in the UK) aux diesel heater that burns derv on a cold day to heat the cabin air before the engine warms up enough to heat it.

I can't say I've ever seen a fuel tank heater even on older dervs where waxing could be an issue. I have seen a heater pre fuel filter, but it's been under the bonnet not in the tank.

I've had a google and a look through some workshop manuals and can't find any reference to it, but then I might be missing it.

Well you learn something new every day, thanks.

Ahh I wonder if you have mis-remembered that?

I dont think so, but maybe my assumption that the build-in heater is still present on all VAG diesel cars might be wrong. I had a luxery version of the Golf III (GT TDi 110 pk), so maybe I had more accessories than other models. Anyway, I am pretty sure that the warning about filling to the max was very clearly described as stop filling after the first click since the fuel might expand or bump out. And my manual stated that damage might occur if the level of fuel in the tank become below the minimum of 7 liters.

I dont think so, but maybe my assumption that the build-in heater is still present on all VAG diesel cars might be wrong. I had a luxery version of the Golf III (GT TDi 110 pk), so maybe I had more accessories than other models. Anyway, I am pretty sure that the warning about filling to the max was very clearly described as stop filling after the first click since the fuel might expand or bump out. And my manual stated that damage might occur if the level of fuel in the tank become below the minimum of 7 liters.

Fair enough, I certainly didn't have that on the MK I Octy TDI 110, but as you say the Golf did have a lot of toys.

Either way, the fuel will heat up due to returning fuel anyway, so it's wise not to overfill it.

If you're going straight out onto a motorway or something then I think it wouldn't be an issue to brim as you'll be burning it off quicker than you're heating it up mind.