The reason I brought this up is the common thread about all electric pumps is failure of the electric motor. Seldomly, any more since we are using fuel bypasses back to the tank to prevent cavitation, is there a actual pump problem.
The most reliable pumps (pump only) I can find are the mechanical gear pumps like the RASP, Fuel Boss, Barry Grant, Aeromotive, etc. However you need a ultra reliable motor to drive them. I think that is why they all seem to use the pulley off the crankshaft, belt, pump drive pulley system. If the engine is turning, you HAVE fuel pressure.
I have a family member in the warehouse distribution business (conveyor belts, motors of all kinds that run for years and years without attention). So I asked him where they got the motors that last years and years and are truely industrial quality motors.
Bisongear.com, Groschopp.com.
I needed a 12 volt extremely rugged motor that I could mount somewhere either driven directly or with the pulley belt combination of the RASP, Fuel Boss, that would out last the 1 million miles I plan to drive my truck.
Groschopp has a 12 v dc motor that I think would not need the pulley belt system because it runs at 1100 rpm and I think that would be ok for the RASP or Fuel Boss since they turn at 1/2 of the crankshaft speed. You would have to do a commercial industrial coupling to compensate any mis alignment, but they are readily available. However the motor cost $415, a bit too pricy for me.
Bisongear has a 12 v dc motor that would fit the requirement but it runs at 1948 rpm and with the pulley belt system would really be very close to cruise speed of the cummins crankshaft. It cost $175 and I feel is more reasonablly priced.
So where I am going with this is building a (backup system for me because I already have the RASP) industrial quality motor to drive a mechanical gear fuel pump and mount it somewhere down by the tank. The dc motor should out last the truck, the mechanical gear fuel pump should also out last the truck. That should put this lp problem to bed permanently, you should never have to ever touch it again, ever.
As with any of the mechanical gear driven fuel pumps you have to have a fuel bypass return back to the tank because these pumps will pump way way way more fuel than the VP44 could ever swallow. You set the fuel psi to the VP44 with a mechanical bypass valve that you adjust the shims and springs to get what you want.
The BisonGear pump (051-203-4045, 32 series, 12v 1/6 hp, 1948 rpm, 14 amp, 93 in oz torque) also has a CONTINUOUS rating. That is not spelled out in their web site and the specs there. I called their engineering dept and wanted to be absolutely sure that the motor could run continuously for years at a time if need be. Also notice the other specs of ceramic magnetics, dynamically balanced armature and shaft, heat range able to run continuously unventilated, commercial quality replaceable brushes from the outside, sealed permanently lubricated bearings, etc. IF you would ever have to rebuild it, it is rebuildable by companies that cater to industries (wearhouses, hydraulic lifts, all sorts of industries) that use fractional hp type motors for about $150 total rebuild.
I realize that for my application (backup lp) this is totally gross overkill. However, if you are or have been tossing carter pumps, holley pumps, or whatever at the lp problem, this might be a permanent solution for you.
I know the Walbro 392's seem to be holding up well, the AirTex might also hold up well. They are priced well also. Members are getting years of service out of them at a time.
I think the mechanical gear driven fuel pump has a mean time between failure beyond the ever possible life of a CTD. I wanted to find a drive motor that would match the mean time between failure of the mechanical gear driven fuel pump to kill this lp problem permanently.
Bob Weis
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