oldnavy wrote:
Cowpie1 wrote:
I can understand having a cooler in a vacuum situation that is part of the CRD fuel system and using a lift pump setup. But wouldn't a inline electric fuel pump at about 5 psi do all that is needed? It would keep a constant pressure to the fuel filter and eliminate a vacuum situation and, with that eliminated, a fuel cooler less necessary.
This would be similar to my semi. Just a thought.
But you semi is using older technology then your CRD as far as fuel pressure goes I will assume (yes, I know what it spells) and these high pressures means the returning fuel has been heated by the high compression fuel IP and should be cooled before returning to the tank, except in cold weather. Our '02 automatic VW TDI, which has a higher pressure pump then the manual tranny model, had a return fuel cooler as standard equipment and was thermostatic controled. This helps to prevent the fuel from breaking down and releasing bubbles into the fuel and a mirried of other problems when the fuel overheats.
Don't think older technology. 2006 Cummins ISX engine. Fuel gets pretty dog gone warm in my semi tanks. Expecially when I get down to a low level. There is considerable hot fuel coming back to the tanks from that 14L engine. They will vapor water that comes in contact with the external surfaces of the tanks.
Either way, it seemed that providing an inline pump that provided about 4.5 - 5 psi would eliminate 90% of the problem some experience with air in fuel. Just eliminating the vacuum condition from tank to fuel filter would go a long ways. Pushing the fuel would be far better than sucking it. At least going that route first would be far more inexpensive and less time consuming. Sometimes the simplest solution is the best. Not always, but sure worth a look see. An ounce of prevention is worth a pound of cure instead of a pound of prevention worth an ounce of cure. If hot fuel was still causing a problem, then look into a fix for that.
A simple to install inline pump would go a long ways, and problably cure most of the problems that some experience. there will always be a few that need more than that. Having a inline pump solution posted here for most users would be a big plus. Then having addtional fixes for the few would be icing on the cake. Heck, some here have never experienced (including me) air in the fuel problems, having to reprime, etc. I am looking at an inline pump solution just to ease my mind on the suction condition. Compared to the larger task of lift pump and cooler, it is like doing your EHM (thanks for that!) as opposed to a Provent.