Fuel cooler - bad in the winter?

[Mark Rinker]

I was underneath one of my trucks last week, and spotted the fuel cooler. Beings it was about -5 that day, it was about as useful as the proverbial **** on a boar.

Could this cooler actually work against efficiency in the winter time? How about a 'duct tape winter front' for the cooler during temps under 0 degrees?

I was tempted to experiment, but decided to post this question before proceeding.

[jbplock]

Mark,
Interesting question … seems like the risk of fuel gelling would be highest when the truck had been sitting in a very cold environment for an extended period of time and fuel in the tank, lines, and cooler reach ambient temperature ... i.e. outside overnight. In this case the cooler would not come into play… If the fuel hasn’t gelled and the engine starts, one would think that the OEM fuel filter heater and heat from the head/injectors would begin heating the fuel and overcome the effects of the cooler… On the other hand the choke point for gelled fuel is the filters so if fuel is cloudy at start-up, maybe the cooler could push the fuel over the edge if it was untreated.. covering it might help? .. Another scenario might be someone running untreated fuel on a long trip and driving from a warm climate to a very cold one. ??


Personally, in 22 years of driving diesels in cold upstate NY winters I’ve never had the misfortune of dealing with gelled fuel.. might be interesting to experiment using a Predator (or similar tool) to monitor fuel temp under different conditions .. i.e. with the cooler covered/un-covered on cold days.

:)

[Mark Rinker]

My thought was over time on a cold day, the fuel will heat up slightly due to the fuel circulating back to the tank through the return lines. The cooler would offset this effect on cold days, when the extra heat could help to keep fuel from clouding or plugging fuel filters.

[DieselMonk]

I noticed that fuel cooler as well on my LBZ the other day. In my opinion the fuel cooler is good in the summer, when things are warm, but it won't do anything in the winter at all, as the fuel is already cold. Things like metal don't get a wind chill factor, so the fuel cooler won't cool diesel further down than the outside temperature. In other words, it doesn't matter what you do with it in the winter, there is no benefit. Now that little bit of heat that comes through the fuel return line will do nothing much to heat the tank as the tank is not insulated either to keep the heat and it would take a very long time. VW will actually "tiger loop" the fuel (short circuit the warm return line with the cold fuel supply line)at the filter when it is cold, to heat the filter and prevent waxing it up. The return isn't then used at all until it is getting warmer. I am not sure about the LBZ at this point, but I am sure GM heats that fuel filter up somehow. That fuel cooler is definitly not good for WVO drivers.