MazdaGuy42

iTrader: (1)

I'm so close to finishing my Single Conversion and taking my FD out for it's first cruse but I'm stuck.

This is a fuel system question and here is what I have:


SS Braided Line (in "3" sections, i.e. I got rid of the hard lines under the coils)
taped factory primary rail for -6 fitting to eliminate FPD
850cc in primary (cleaned and flow tested at Marren)
Factory banjo line from primary to aftermarket secondary w/adaptor from KGparts
1680cc injectors (cleaned and flow tested at marren)
All Summit -6 fittings (like earl's)
SX performance FPR



Here is my problem, I can't get my FPR above 20psi and when I stop running the fuel pump at the diagnostics box the needle goes right down to "0." I realize I have a preasure leak but I can't find it anywhere! I have ran the pump over and over for several minutes and there are no visible leaks and no gas smell. I've checked it all:

Felt and examined all of my fittings____Bone Dry
Pulled the primary rail while under preasure____No drips Bone dry
Pulled the secondary rail along w/primary_____Front injector had wetness on the tip but under preasure no signs of leak.

pulled Leading plugs and manually cranked motor___no wetness came out, just dry puffs of air.

examined where secondaries meet the rail____Dry, no smell
FPR (bought used but installed overhaul kit)_____Checked the new diaphram, fittings with no leaks or smell.

felt and examined where the lines are connected for the feed and receiving at the drivers side fire wall____ very dry no leaks

Checked my fuel filter above the diff. for leaks____Dry no signs of leaks


I'm telling ya I've looked over and over everywhere and there are no leaks to be found. the only thing I can think is that I have my feed and return lines at the firewall backwards or that maybe I have some kind of bad "O" ring at the fuel pump because my engine bay has no signs of a leak.

Any help is appreciated!

D

cewrx7r1

iTrader: (2)

Most likely you do not have your fuel pressure regulator and that area plumbed correctly. Go back and look at the instructions and check everthing out.

That is assuming that you tried to adjust the pressure with the FPR adjusting screw and it did not work.

This has been discussed much in detail because of other newbs having the same problems. Some of these threads have diagrams and pictures.

GO SEARCH.

MazdaGuy42

iTrader: (1)

What instructions? my thread says that I bought the regulator uses and that I installed a overhaul kit.

my plumbing goes like this:

a good 1 and a half feet+ of SS braided line starting from the feed at the fire wall meeting up to the primary fuel rail.

I adapted the factory banjo line to the new secondary fuel rail.

from the secondary rail I have nearly 2 feet+ of SS braided line going to my regulator mounted by the drivers side shock tower.

from the regulator I have another foot and a half going to the return.

All of my connections use the blue and red fittings from Summit except where they meet the feed and return.

D

MazdaGuy42

iTrader: (1)

I just called SX performance and the tech said to disconnect the return line from the fire wall and let it hang, then pressurize the system. If anything comes out then the ball of the diaphram inside the regulator isn't seated right. So I did and no leaks at all.

Next I went back to pulling the leading plugs and hand cranked the motor and again no leaky injectors.

everything is pointing to a leak at the pump which is a walbro 255 installed a year ago.

MazdaGuy42

iTrader: (1)

Problem solved! the rubber "O" ring at the fuel pump where the nozzle meets the hard line was all bent out of shape causing the leak.

cewrx7r1

iTrader: (2)

Do not put that crap back in the gas tank.
Cut off that crappy Mazda so called fitting, and replace with a piece of high quality FI hose from the steel pipe to the pump outlet.

I did this years ago when the nylon piece of crap in mine broke.