Steve, Pumps seem normal, work them harder and they will draw
more amps. same as climbing an aircraft, quicker climb = more
hp. Looks like your regulator cannot handle the flow as you have
concluded. Does the toyota reg altitude compensate? Forget what
my reg is but cost a lot of money, -- that I remember!! Neil.
Hi Guys
Hi Peoples
Here is a photo of our parallel pumps plumbed with
3/8 aluminium lines feed from a 28 gallon header tank above to
the right.
Fuel then passes through the firewall and race
filter before feeding the rail and returning via the pressure
regulator (4cyl toyota reg)
back through the firewall to the header tank, again
in 3/8.
I did further measurements today.
1. Bottom Pump only ~8A and 48psi - Turning both
pumps on this pump draws 9.9A and produces a rail pressure of
65psi
2. Bottom Pump only ~9.9A and 44psi - Turning both
pumps on this pump draws 14.8A and produces the same rail
pressure of 65psi
So bottom pump goes from 8.0 -> 9.9A (1.9A
increase) under higher head pressure
Top pump goes from 9.9A -> 14.8A (5.1A increase)
under same head!!
Clearly Pressure Reg bypass capacity is inadequate
for both pumps, perhaps with even one pump running.
(I don’t have data of fuel pressure under load to
see if it drops as power is applied)
I think I modelled the pump layout/manifold after
seeing someone else’s and not sure if it causes any problems?
The pumps came from eBay stating that they were
genuine Walbro and now I’m wondering.
Cheers
Steve Izett
Glasair Super II RG Renesis 4 port RD1C EC3 EM3
<Mail Attachment.jpeg>