Thread: Deleting fuel cooler.

Originally Posted by admiralranga

Less relevant here but I do suspect the coolant ones do a decent job of warming the fuel up when it's very cold.

No, IMO it's not the case cos the fuel returning from the head can't be colder than the coolant returning from the radiator whatsoever(these are passing through the fuel cooler), when it's cold it's like the cooler is not there... hence the cooler's thermostat(which the newer square type coolers dont even have):

Fuel cooler
The fuel cooler is located on the right hand side of the engine and is attached to the inlet manifold. The cooler is
cylindrical in design and has a coolant feed connection at its forward end. A 'T' connection at the rear of the cooler
provides a connection for the coolant return from the heater matrix and coolant return from the fuel cooler.
The 'T' connection houses a thermostat which opens at approximately 82°C. This prevents the cooler operating in
cold climates.
Two quick release couplings on the cooler allow for the connection of the fuel feed from the pressure regulator and
return to the fuel tank. A counter flow system is used within the cooler.
Fuel flows around a coolant jacket within the cooler and flows from the back to the front of the cooler. As the hot fuel
cools travelling slowly forwards it meets progressively colder coolant travelling in the opposite direction maintaining a
differential cooling effect.

I just picked up a late 2A rectangle style cooler, the size difference between it and the older cylindrical unit is amazing.

I'm sus on it, we're talking an order of magnitude smaller? re; surface area.

Originally Posted by FNQLR

I just picked up a late 2A rectangle style cooler, the size difference between it and the older cylindrical unit is amazing.

I'm sus on it, we're talking an order of magnitude smaller? re; surface area.

No reason for suspicion, they work well enough, the size is not so important cos it's a different, more efficient technology... those for the TDV6 are not much bigger

can someone put a diagram of how to plumb the D2A fuel cooler to a D2 this would be great thanks.

Originally Posted by laney

can someone put a diagram of how to plumb the D2A fuel cooler to a D2 this would be great thanks.

You'll need a tee piece to replace the old one of the cylindrical cooler, and a heap of new hoses as the early ones don't fit.

I've decided to just fit an air cooler to mine for this reason - it's just too ugly a setup with diy hoses.
Will be running the fuel through an old tranny cooler, and have blanked off both lower spigots on the radiator, and also the oil cooler.

It does neaten up the engine bay considerably, I can now see into the chasm of chafe that is the inlet side of the engine. Can even reach the starter top nut from the guard

Originally Posted by sierrafery

Even if it doesnt explode IMO deleting the fuel cooler is a VERY bad ideea on a Td5 ... it will become powerless once the FT gets above 75*C and without the cooler it will definitely go above... the ECU reduces the injected quantity based on FT input too also your fuel pump will fail more often getting too hot fuel on the return, especially if the level in the tank is low

I spoke to my local indie about this very thing, and he said the same thing. Don't do it, he said.

Very interested in the idea of using one out of a D2A or D3 though. That's just plumbing.

Originally Posted by FNQLR

I just picked up a late 2A rectangle style cooler, the size difference between it and the older cylindrical unit is amazing.

I'm sus on it, we're talking an order of magnitude smaller? re; surface area.

I'm not a 2/2A person, but from what I've read the 2 cooler is a shell and tube and the 2A is a flat plate. If that is the case, you probably underestimating an "order of magnitude". The efficiency difference between the two would be *significant* and the heat exchange surface area would be at least an order of magnitude increase and the turbulence with a flat plate is significant increasing the heat exchange efficiency considerably. I am a D3 driver, and the fuel temp increase on the high pressure side of the fuel system is significant. If you don't cool it, "bad things" will happen. Not just the de-rating, but loss of viscosity affecting the lubrication of the pump and injectors.

Manufacturers don't put parts in "just because". Every part incurs a $$ penalty. It wouldn't be there if it didn't impact driveability or reliability.

Just did an 80k trip sans cooler to see / baseline

coolant temp of 82 deg
ambient temp of 14 deg (melbourne )

1/3 tank of fuel

city and hwy driving

Maximum fuel temp of 66, average around 62
Running cooler than with the fuel cooler fitted.


I can image that with an outside temp of 40 degrees this would be an issue, could be looking at high 90's ?