Fuel Cooler

[eagle6]

Can anyone tell me what the fuel cooler does - apart from cool fuel - is it a critical part of the system?
I've been told the fins on mine are damaged and it should be replaced.

How much, where is it and is it an easy job to do?
Any tips to make the job easier?

Cheers

 

[cheshire cat]

if it's not leaking and you're not going to thrash it 'round Spain I wouldn't bother,,more important not to flog it down the motorway on a hot day with the tank empty

 

[Andrewcupra TDI]

spose depends on car ,

i believe mine sits underneath the drivers footwell (underneath the car )

so in simple terms look under drivers sill and you will see alittle radiator style cooler

as for changing or not , i wouldnt know , check scrappies or parts finer on the web

 

[devonmikeyboy]

Sits under the car and just cooler the fuel as it returns to the diesel tank. As it`s placed under the car i doubt anyone one this site has a car that doesn`t has some damage on the cooler from stones,speed bumps,pedestrians . Anyway unless it`s leaking or going to leak i wouldn`t bother, if it`s going to leak nothing stopping you brazing over the damaged area etc if you wanted to as your not going to set diesel on fire with a flame.

 

[Toledo_130]

just noticed on saturday the fins on my cooler are all bent..looks like the previous owner was rash and caught them, would it be advisable to try and straighten them or will they be fine??

 

[devonmikeyboy]

Leave the fins alone, it`s not hurting. Your do more damage trying to bend them back.

 

[sssstew]

The purpose of this is to cool the fuel on its return to the tank, it gets to a high temperature because its highly compressed and the excess fuel is fed back to the tank, now with the petrol tanks being made of plastic now very hot fuel could cause some damage so hence its cooled on its way back.

 

[Viking]

Hey Emily, how can an led light be used to cool fuel?

 

[Viking]

Oh, I know enough about led lights to know that they run cooler than normal bulbs, but what the hell does that have to do with cooling diesel fuel as it's returned to the fuel tank?

I sense a bit of spammage here.

 

[warren_cox]

Oh, I know enough about led lights to know that they run cooler than normal bulbs, but what the hell does that have to do with cooling diesel fuel as it's returned to the fuel tank?

I sense a bit of spammage here.

Me love you long time is coming to mind for some reason.

 

[Viking]

Oh, and my name is not "Mr Sig".

 

[warren_cox]

Oh, and my name is not "Mr Sig".

No, it's

My Sig.

 

[DPJ]

I am so sorry

If you're sorry, why the ?

 

[DPJ]

I am not the professional , and only a surfer of internet . But i hope can help you . Just now I sent some quotes to you was deleted. In the quote i send the website for you, but I am sorry to fail to send the website, so about the website's detail you can't know

You are being paid to promote a Chinese website that sells led bulbs online. Doing so here is spamming and is most unwelcome.

 

[fenwick458]

the fuel cooler (as already stated) is in the return lne back to the tank, it's purpose is to stop the fuel in the tank getting too hot which could damage the level sender/pump/tank.

this cooler was only fitted on the PD engined cars.

adding additional fuel cooling methods to the PD engine is not going to make a difference, the fuel is pumped through the filter and up to the tandem pump where it is then fed through a tube running inside the cylinder head that feeds the individual injectors. this "distributor tube" is cross drilled and hot return fuel is mixed with the incoming fuel so as to even out the fuel temperature accross all 4 cylinders. and also, the cylinder head is hot, and this tube is going to be just a hot (~90) so basically, the fuel is going to get heated up in this tube before it gets to the injectors no matter how cold it is before you put it in the head.

also in the PD fuel system cold fuel can lead to injector failure and poor spray pattern.

on a rotary engined TDI this may be different and fuel cooling may be a necessity but i wouldn't know about that!

 

[jabbasport]

Fuel cooling isn't just to protect the tank..

Diesel is thicker at lower temperatures, optimum temperature for Diesel fuel is most efficient around 70 degrees c, providing a better combustion. The cooler's there to try maintain a constant diesel temp too

Kev

 

[devonmikeyboy]

Fuel cooling isn't just to protect the tank..

Diesel is thicker at lower temperatures, optimum temperature for Diesel fuel is most efficient around 70 degrees c, providing a better combustion. The cooler's there to try maintain a constant diesel temp too

Kev

I would have thought most people would know diesel is thicker when cold. The fuel cooler hasn`t got a thermostat to control it so cools the diesel no matter if it`s hot or cold. After a few minutes driving the fuel temp will be constant anyway as it`s circulating and mixing in the tank.

 

[Muttley]

devonmikeyboy wrote

I would have thought most people would know diesel is thicker when cold. The fuel cooler hasn`t got a thermostat to control it so cools the diesel no matter if it`s hot or cold.

BUT the valve in the top of the fuel filter is thermostatic, and diverts warm fuel from the return line straight back into the filter when the temperature difference is significant. If the returned fuel is hot (i.e. the engine's warmed up) and the flow from the tank is cold (i.e. it's a cold day) then hot fuel is mixed in to the feed line. The filter is before the cooler in the return line, of course.

After a few minutes driving the fuel temp will be constant anyway as it`s circulating and mixing in the tank.

The valve in the fuel filter makes sure that fuel sent to the engine gets warmer as soon as possible.

 

[fenwick458]

devonmikeyboy wrote

I would have thought most people would know diesel is thicker when cold. The fuel cooler hasn`t got a thermostat to control it so cools the diesel no matter if it`s hot or cold.

BUT the valve in the top of the fuel filter is thermostatic, and diverts warm fuel from the return line straight back into the filter when the temperature difference is significant. If the returned fuel is hot (i.e. the engine's warmed up) and the flow from the tank is cold (i.e. it's a cold day) then hot fuel is mixed in to the feed line. The filter is before the cooler in the return line, of course.

After a few minutes driving the fuel temp will be constant anyway as it`s circulating and mixing in the tank.

The valve in the fuel filter makes sure that fuel sent to the engine gets warmer as soon as possible.

ever tested the thermostatic tee before?i have and mine was broken, contantly used to dump fuel in the filter so on prolonged WOT runs the temperature would creep up to 75 as hot fuel out of the head was pre warming the filter and incoming fuel even more.
what i have done with mine is smashed out the ball and spring, tapped the inside of the tee and screwed a 8mm bolt and cut the head off in there so it's now blocked off and always diverts fuel straight back to the tank. it takes about an extra 5 mins driving for the fuel to reach 65 now but it stays more constant thay way and only ever climbs 1-2 degrees.

 

[trebormint]

What is the ideal fuel temp then?

What would be too cool and too hot?