Started working on my Airdog pump and low pressure fuel gauge today.  Pressure tested at the Airdog port and it shows 21 ½ pounds on one of Vulcans gauges.   I’ve read people like 15-17psi .  I assume the psi would be the same closer to vp44.

 

 Question 1…Is 21 psi OK or is it too high and might damage pump?   Model of pump is DF 100 which I think is not adjustable, but not 100% sure.

 

The pump is mounted with the fuel line from Airdog just the way they ship it and was not cut to fit.  So pump is about ½ way between VP44 and sump at tank.  To take up the slack in the fuel line,  the guy put a circle bend in the line under the airhorn and already chaffed.  Line is also rubbing on the frame at several places on frame.   If I put the pump on outside of frame there is lot less to rub on.  But I have to raise pump about 8 inches  (pumping up hill usually not good for pump I know)  The bolts holding pump in place are almost finger tight.  If bolts to mounting bracket were tight, looks like they will smash the brakelines.  But I could put in a spacer of some sort.  But would prefer to mount airdog on outside of frame and extend fuel line to vp44 and shorten fuel line from pump to tank.

 

Question 2…Are these pumps better at pushing or sucking or does it matter?   And going vertical 8 inches might be a “drag” on system or would it be?

 

Thanks

Edited October 6, 20168 yr by 015point9

21 psi is fine.  14-20 is normally the "ok" range.  I ran 25 psi for years with no issues. 

 

They are better as pusher pumps.  I would cut the excess fuel line out.

True there is better pumps out there but keep in mind of locations, size, etc.

Best to measure fuel pressure between filter and Vp, 21 psi. Might be a little high at idle, but just as important is  the pressure drop at *** throttle. I dont think you should see anything less than 14 psi. under load

my AD is installed the same and i did leave a loop at the pump. it does not seem to hurt any thing but one day i will cut it out. Just not a high priority now for me