Boiling Fuel Issue

[mbarryracing]

My issue is a little different, I definitely am NOT boiling the fuel in the rail. I know this because my tunnel under the gas tank looks like it was used as a charcoal grill and you can watch the fuel rolling boil right around the in-tank filter when you look down inside the tank.
I tried using an Ebay special Racing Oil Cooler and plumbed it in the return line after the rail (low pressure), mounted in the nose where I mount my Motec ECU.
Mid season last year it cracked at the end tanks and started spraying fuel in the nose. Great!
So the concept was good, taking the heat out of the fuel before going back into the tank to prevent constant rising in-tank fuel temps... but I failed at the implementation

 

[Northernboy]

Vmax4, I am sure what Hurricane would supply is a fitting the would go on the end of the stock rail to allow flow through. Ideally fuel should go into the stock rail then out of the other end. Then it would go into the MCX rail and out of the MCX rail then to your regulator. Problem is the MCX is closed at the one end. I am looking at drilling and tapping my MCX rail to do this. Just wondering if anyone has done this yet?

 

[Vmax4]

That is what I am saying....... no exit on the tail end of the fuel rail......

 

[Northernboy]

I run flow through on the stock rail with the fitting then into the MCX with the regulator connect in between with a tee. Not Ideal but it works until I can find away to get flow through on the MCX rail.

 

[TURBLUE]

For a few seasons I have struggled with boiling fuel in the tank on my Apex. At slower speeds the heat from the header soaks up thru the tunnel and gets the fuel so hot to the point it has an actual rolling boil in the bottom and gets the intank pump warm enough to raise the resistance and quit running...
I have had to insulate the tunnel from the headers with a Thermal Barrier 1800 degF Inferno Shield from Heat Shield Products... I tried running a fuel cooler, but it didn't survive vibration.
I have even seen the fuel boil in a stock Apex, but since they don't run a higher fuel pressure with boost they are less susceptible to running issues.

yup,,,,,same as me.......mine still will act up on warm slow days, but for the most part it doesnt .......its scary how violent it boils when you take the cap off and look in....

 

[Vmax4]

Has anyone tried to use a coolant additive? I know the heat is from the header, but trying to get a lower coolant temp, might help????

Anyone have any products?

 

[mbarryracing]

yup,,,,,same as me.......mine still will act up on warm slow days, but for the most part it doesnt .......its scary how violent it boils when you take the cap off and look in....

It starts to boil when the fuel level / volume gets down around 3/8 full, typically when riding slow like thru a tight woods or thru town to the gas station to fuel up then stop and shut it off. The heat just soaks thru the tunnel.
Worse on warm days but did have it happen on cold days too. Seems like slow speeds there isn't enough cool air being pumped thru the tunnel by the track.

Has anyone tried to use a coolant additive? I know the heat is from the header, but trying to get a lower coolant temp, might help????

Anyone have any products?

I have been using Redline Water Wetter as a coolant additive in race engines for years, suppose to help transferring heat from the metals to the liquid and visa versa. Using it in my Apex to help with the coolant light coming on in marginal snow conditions, doubt it would do anything for hot fuel because it still gets baked from the engine heat.

 

[rxrider]

The Apex has a regulator and fuel return at the end of the fuel rail returning unused fuel to the tank thus the fuel is not sitting in the rail but continously circulating. This is what HURRICANE suggest doing on the Nytro.

The fuel tank has to be insulated heavily not to soak up heat from engine parts or exhaust parts.