Fuel Cooler

[WisconsinHick1]

How important is the fuel cooler?

I am thinking of removing mine when I install my FASS. I understand it helps cool the fuel that is returning off the motor and of course cooler fuel is better for performance. However neither Ford or Dodge have one.

Am I missing something?

 

[Mike L.]

Ford now has one maybe two on their new truck. I think they are important.

 

[BHoward6.6]

I have seen my fuel temp hit 195*.

 

[DMAXchris]

I want to add another one somewhere.

 

[WisconsinHick1]

Wow 195˚ but you are also in a hotter climate then me.

Still kind of interesting that there is that much fuel being pushed back into the tank.

 

[BHoward6.6]

In all fairness the 195* fuel temp was typically seen at low OAT's (50*80*). Mostly because I was pulling my 5th wheel from sea level to 4000'.
IIRC fuel temp's are around 140* while emty at highway speeds.
I would leave the fuel cooler.

 

[super diesel]

When it's really COLD out side (sub zero), as I'm sure you see as well, I put a cover over mine to help the fuel warm up in the tank.

 

[hondarider552]

I have a big tank blocking my fuel cooler, im sure I dont want to see my fuel temps in the 115* summers

 

[quentomania]

Should be a more efficient burn with cool fuel. Big trucks used to have warm returns and they pulled a little better when you just fueled up imo. These new 550 cummins have fuel coolers too.

 

[Mike L.]

I have seen my fuel temp hit 195*.

You are losing power at those temps. 75F is the optimum fuel temp according to Cummins. The problem is, it is difficult to to even get it to ambient temps in the summer or under a pulling a big load. Dual fuelers will also raise temps past 175F. When the temps get close to 200F and above, the ECM pulls power back.

There was a thread a few years ago at DP where the dealer installed a big tank and didn't have enough room for the cooler so they left it off. He was towed back a few days later with a fuel boiling issue under load. The dealer reinstalled cooler and solved the problem.

 

[05_LLY]

I have seen trucks with fuel temps in the 230s, running a truck low on fuel seems to increas temps especially when towing in warm weather!

 

[JD Dave]

Most of the pulling trucks don't have a fuel cooler. Do you think it would be worth while running my return through my ice/water box then. I only have a 5 gallon fuel cell so I'm guessing yes.

 

[Mike L.]

I have seen trucks with fuel temps in the 230s, running a truck low on fuel seems to increas temps especially when towing in warm weather!

The fuel in our trucks is mainly cooled by the fuel in the tank and not the cooler. The lower the fuel level in the tank, the hotter the fuel gets. I found this out with a infra red camera.
My old buddy LosLobos in Oregon tested this with his camera and follewd the fuel back to the tank. The camera showed Red ( hot ) to the cooler and Red out of the cooler and Gray ( cool ) when the return fuel hit the tank.
We then installed my fuel cooler and the fuel showed Red to the cooler and Gray when it left the cooler.
It was a very interesting study.

 

[WisconsinHick1]

The fuel in our trucks is mainly cooled by the fuel in the tank and not the cooler. The lower the fuel level in the tank, the hotter the fuel gets. I found this out with a infra red camera.
My old buddy LosLobos in Oregon tested this with his camera and follewd the fuel back to the tank. The camera showed Red ( hot ) to the cooler and Red out of the cooler and Gray ( cool ) when the return fuel hit the tank.
We then installed my fuel cooler and the fuel showed Red to the cooler and Gray when it left the cooler.
It was a very interesting study.

So you found that the stock cooler does nothing. However your cooler does the job.

One of the reasons I bring this up is my truck gets drove maybe 5000 miles a year and will be more on the lines of 3000 miles after I finish my motor build. I just looked at the FASS instructions and saw I needed to remove it to hook everything up so I figured maybe I'll just delete it.

 

[Texas Chevy]

You are losing power at those temps. 75F is the optimum fuel temp according to Cummins. The problem is, it is difficult to to even get it to ambient temps in the summer or under a pulling a big load. Dual fuelers will also raise temps past 175F. When the temps get close to 200F and above, the ECM pulls power back.

since fuel temps effects power does it also effect mileage?

 

[Mike L.]

since fuel temps effects power does it also effect mileage?

Absolutely.

 

[Mike L.]

So you found that the stock cooler does nothing. However your cooler does the job.
.

I didn't say the factory cooler did nothing, just didn't help much under adverse conditions. The cooler I used to sell made a big difference.

 

[GeneralTJI]

I wonder if a fan would help.. since the cooler is in kind of a weird place... thoughts?

 

[taylorbok]

mine is totally blocked by titan tank, could prob use a fan

 

[Chevy1925]

I wonder if a fan would help.. since the cooler is in kind of a weird place... thoughts?

maybe in cooler climates. doubt it would help much out here