fuel boiling!
Never thought of that, you may have just pegged it!!!
Some old dirt bikes did that if I remember right.
When problem occurs:
Engine is very heat soaked
Fuel pump wants to work, but can't build the right pressure, i.e: 48psi, only goes to around 25psi sled will try to fire and spit and sputter, then die again: seemingly a lack of fuel, or the injection system is not working correctly, or lack of spark????
I"ve tried to blow on the return line from the fuel pump to force fuel through the tank into the system, worked once in a while but not really.
At the same time the RB3 box was very hot to the touch.
My initial thought was the fan relay is not working, or the temp sensor in the thermostat housing is faulty, therefore not kicking on the fan,, or the overheat light.
I've unplugged the RB3 box and the fuel pump still acts the same when turning the key to build fuel pressure, just wont start with the box unplugged.
Same issue with the box plugged in, but tries to start and dies again.
Now that you mention the fuel boiling issue, that seems logical, the symptoms are pointing in that direction.
I will go through the cooling system processes today and make sure that everything is working right.
If that fan is not coming on, no cooling back there at all.
Can you wire for fan operation all the time when the engine is running?????
Can you get a different sensor to kick the fan on earlier in the heating process?
Can you install an optional fan to blow downward on the fuel rail?
Can you wrap the fuel rail to protect it from heat?
We need to figure this out, I'm gettin frustrated, but I think we are on the right track now....
Thanks for any help....