Airdog thru sump and Carter thru draw straw?

[015point9]

Currently I have a FASS draw straw and a sump with a new Airdog DF 100 system.  The new Airdog system is hooked up to a sump and currently the draw straw is plugged off at the fittings. I recently got a Carter for a back up pump.  I would like to keep the sump for the Airdog and its filters and run a fuel line close to the VP44 with shut off valve.  And then hook up the carter via the draw straw thru to the stock fuel filter on motor then to a shut off valve.   With a shut off valve on each line,  I would open that valve for the line I’m using at the time.  Then install pressure gauge, then to VP44.  And install a toggle switch for on/off switch to each pump.

Questions…

Can I use the draw straw for the carter pump?  

Any of this have any merit? 

 

(For more back ground, and why I want a back up system)

9 year old FASS pumps installed on 01 Dodge, many miles from home and the low fuel pressure light comes on.  I had no pressure gauge but currently installing one.  

Mechanic  (1)  installs new fuel modulator as fuel was leaking around the top.  But I’m not sure if modulator really was the problem.  Mechanic did come recommended,  but believe it or not.  But he couldn’t get it started and didn’t know how to prime the fuel system.  Great guy but turned out didn’t know anything about diesel.  (At the time I even knew how to prime the fuel system).

Mechanic (2)  said mechanic (1) screwed up the wiring so he re-wired  top of fuel modulator and the FASS pumps.   Mechanic (2) felt the replacement fuel modulator straw was not strong enough and the straw was collapsing under pressure so he also installed a FASS drawstraw.   Drove it for one day and felt like it was running out of fuel.  I took it back and basically he wanted to throw more parts at it.

Mechanic (3) Looked at everything done by other mechanic’s and decided the best thing to do was to go with a sump and new pump system (airdog).  His job did work and got us home, but oh what a sloppy install.  My truck is 2 wheel drive (so sort of low ) and the fuel line hose is just hanging down from sump , the mounting bracket the pump is mounted to is rubbing against brake line, wiring job looks like a kid did it, etc.   

So going to clean up the mechanic’s  (3) work and thought hooking up the cater pump to draw straw while I’m at it might be good idea.

Thanks 

[Mopar1973Man]

Personally... Just way too confusing. Remove all the stock supply fuel lines and stock Carter lift pump. Now install the FASS on the sump. Cap off the old fuel pickup module (supply). Just install only one fuel system don't bother with back up stock systems. 

Edited October 28, 2016 by Mopar1973Man

[JAG1]

Sorry for the troubles you had. It's good you have the sump. Mine is acting funny when I let fuel go lower than 1/4. So I need the tank sump to stop the funny sound and sudden FP drop when sucking air.

[dripley]

I dont have a back up system but sometimes think it would be nice. Lost my AD pump about 1.5 years ago and it would have been nice to have. I think it is you preference if you want one. It should work as you describe though the fuel will be unfiltered where stock you would have a screen to keep any big stuff out of the Carter. Not sure how big of an issue that would be though since hopefully you will never have to use it.

[IBMobile]

When I took my Carter vane pump apart there was a wire mesh filter on the inlet side of the pump.