Does anyone know the purpose of the "to injection pump (in)" line. My latest theory is when downhill, the fuel pump pulls air from the tank via the "injection pump (out) line, through the pump and then through the "to injection pump (in)" line.
First off, that drawing ain't right. Fuel flow should go... Tank bottom to separator single banjo. Separator double banjo (a) to lift pump in. Lift pump out to fuel filter in. Fuel filter out to injection pump in. Then, injection pump out to separator double banjo (b). That book drawing only shows one connection to the fuel filter.
Trying to find correct picture
Hmmm, where's the lift pump in that description? And the return to tank line?
I was thinking the fuel filter housing is integral to the pump so no outlet shown?
Went back and fixed it
how bout the return to tank line?
The rear connection on the tank comes from here, I think.
Does your manual show a similar picture to the one I posted?
Anyone know if this is a check valve?
well I put a check valve in the return to tank line. Ran great for an hour all downhill then **** the bed again.
Still fighting this problem. Took the fuel filter off today and it is not full of fuel... actually looks like the level is at the bottom of the threaded nipple that the filter screws on to. Does this seem correct? I would've expected the filter to be completely full.
So, if the suction is from the nipple, when going downhill the suction gets exposed to the air that's trapped in the top of the filter/housing. Going to loosen the filter and run the pump in the hopes of clearing the trapped air.
If anyone is having this problem... I removed separator bolts and flipped it upside down. This allowed me to see bubbles entering the separator. Tightened the banjos and bubbles stopped. Seems to be working but time will tell