0 pressure from pressure gauge

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damo99
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Location: melbourne australia

0 pressure from pressure gauge

Post by damo99 » Sat Jul 09, 2016 5:42 am

i am setting up fuel on my 61 bus ,i already have microsquirt
running ignition for the last 3 months and now to fuel , anyway
i set up all my fuel system for injection , 044 pump , sard regulator with pressure gauge,
braided line throughout fuel system and T peice return system (home made not cb performance).
i have it all set up ,no leaks but when i power up the fuel pump (wired to a separate battery to test system)
the pressure gauge showed 40psi pressure then slowly dropped of to 0 .
when i disconnected then re connected the fuel pump it came back to 20psi
then back to 0.
it feels like there is pressure in the lines
i try to adjust the reg but nothing changes
i can hear fuel going back to the fuel tank through the T .
its not like a beetle where you have about 10ft of fuel line to the tank ,
my longest line is 19inches long (tank is behind the motor )

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andy198712
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Re: 0 pressure from pressure gauge

Post by andy198712 » Sat Jul 09, 2016 6:02 am

is the reg hooked up correctly?

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Jadewombat
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Re: 0 pressure from pressure gauge

Post by Jadewombat » Sat Jul 09, 2016 9:19 am

Can you post a picture of your setup?

damo99
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Re: 0 pressure from pressure gauge

Post by damo99 » Sun Jul 10, 2016 3:08 am

i checked the fittings on the regulator with the sard manual .
they are all on right
i will take a few pictures tomorrow and post them up .
today i changed the fuel pressure gauge thinking it could be blocked .
well as soon as i did that i got 5bar of pressure on the gauge ,so i adjusted it to 3bar .
it stayed there for a while and then started dropping down to just under 2bar and stayed there
with the fuel pump running constantly.
i might have some dirt in the pressure regulator ,so tomorrow i will clean it out and try again

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Dale M.
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Re: 0 pressure from pressure gauge

Post by Dale M. » Sun Jul 10, 2016 9:52 am

If you cut your own lines did you blow them out before connecting....

Dale
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Piledriver
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Re: 0 pressure from pressure gauge

Post by Piledriver » Sun Jul 10, 2016 2:03 pm

Also, is the pump making any noises sorta like a blender?
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Jadewombat
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Re: 0 pressure from pressure gauge

Post by Jadewombat » Sun Jul 10, 2016 9:58 pm

Just wondering if there is a restriction (other than the regulator) if the pressure is bleeding back through the pump when you shut it off.

damo99
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Re: 0 pressure from pressure gauge

Post by damo99 » Mon Jul 11, 2016 5:25 am

i didn't get a chance to look at it today .
but the pump is making noise like it's working .
if i can tomorrow i will take the system apart and make sure a tiny
piece of braided line didn't go through the regulator and block it .
as it's all screw on braided fittings it's very simple to completely pull
apart in about 10 minutes .
in the system i have a 100 micron filter before the pump
and 40 micron after the pump but before the fuel rail

jhoefer
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Re: 0 pressure from pressure gauge

Post by jhoefer » Mon Jul 11, 2016 1:13 pm

I'll ask an obvious question: do you have enough gas in the tank?

damo99
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Re: 0 pressure from pressure gauge

Post by damo99 » Tue Jul 12, 2016 5:16 am

Last edited by damo99 on Tue Jul 12, 2016 5:22 am, edited 1 time in total.


damo99
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Re: 0 pressure from pressure gauge

Post by damo99 » Tue Jul 12, 2016 5:21 am


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Piledriver
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Re: 0 pressure from pressure gauge

Post by Piledriver » Tue Jul 12, 2016 12:48 pm

044s really need a recirc sump and feeder pump but it should work much better than that.
Check deadhead pressure, should be ~160 psi, may draw 13A.
note this also tests your hose clamps...
I, for one, regularly embrace our new robot overlords, as I am the guy fixing the robots...

damo99
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Re: 0 pressure from pressure gauge

Post by damo99 » Tue Jul 12, 2016 5:17 pm

i think i found the problem when i pulled the system apart,
there was a tiny bit of braid stuck in the pressure regulator..
so while the whole thing was apart
i pulled the tank and gave it a god clean (as good as i could without cutting it open).
So once i got it back together i got 70psi constant, with no leaks.
the only thing now ,is the pump makes soom weird noises(and very very loud)..
so i might change the pump for another one i have from a holden commodore 6cyl.
or has anyone got any recomendations for a fuel pump
i could use (not chev as we don't have many in australia)..

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Piledriver
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Re: 0 pressure from pressure gauge

Post by Piledriver » Tue Jul 12, 2016 7:20 pm

The GM FI pump will probably work fine, although 70 PSI may be pushing it (don't know its spec)
Most GM port EFI runs in the 3 Bar range IIRC, not 5 Bar.

The 044 is a roller cell pump: They do not "suck" well...needs a recirc sump and feeder or it will cavitate and "sound funny"... and loud... and die young.

The 044 is a fine pump, and is flow rated at 90 PSI, and will flow tons at that high pressure...but it needs a bubble-free, fat, short positive pressure feed.

I'd merrily offer to buy it from you for a spare but I'm sure the shipping would be brutal.

Personally i'd build the recirc sump and use the GM pump as a feeder for the 044... esp if you really need 5 Bar+ fuel pressure.
I, for one, regularly embrace our new robot overlords, as I am the guy fixing the robots...

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