BigBlue

I was reading on a chevy site that the Dmax has a fuel cooler on it and I got to thinking. The VP44 uses the fuel to cool and lubricate. And that pump heats the fuel up really quickly. Well, if we put a fuel cooler on the return line, wouldn't that help keep the fuel cool and keep the pump cooler as well? I'm just trying to think of ways to keep the injection pump happy (I've spent enough money on fuel systems as it is and I'm getting ready to spend another $100 in the next couple of weeks). What do yall think? Crazy, or smart? I was thinking of maybe using a small oil cooler from summit as the cooler for the fuel.

AlpineRAM

I'd put a small thermometer on the fuel line (Like the cheap int/ext car thermos) with heater pipe insulation tape wrapped around sensor and line to avoid exterior influence. Then you'd see what kind of fuel temps you get- then decide whether to build that stuff or not. On the Dmaxes I worked the return lines were very hot to touch after driving (you wouldn't want to touch them) and even the fuel tank got warm to the touch. On my dodge the tank isn't really that much warmer than ambient...

AlpineRAM

Redleg

I have thought about that also. Another benefit to that may be the fuel temperature in the tank won't fluctuate so much. It would be nice to maintain a quarter tank reading the next morning, like you had when you shut down.

infidel

I think an easier solution would be to keep the tank full as possible to act as a heat sink.
I've often thought that this was part of DC's reasoning behind having the gauge show empty when it has around 10 more gallons to go.

You would have to have a bypass around the cooler when the weather is cold.

Your reasoning is correct though, when fuel injection first came out on gassers transfer (lift) pump failures were common till they figured out putting the pump in the tank kept them cooler.

Redleg

I don't know about 2nd gen's, but when mine's pushing the E, you better find some fuel or get ready to dig out the wrench.

Crimedog

So that must be what's going on. I had all of these strange suspisions of "where is it leaking form, and who drove my truck last night" (although I would have heard them start it)

Does the fuel really expand that much with just the little bit of heat?

jaconst

mine 95 fuel gauga was awsome seemed real acurate would be a little past F when completely full and 1/4 tank would usually be over 400 miles now my 96 gauge says right on or a little less than F on fill up and 1/4 tank by 300- 350 or so. does anyone hear their sending unit when outside next to truck at idle??