Hello .
New here and did search but not finding what I "think" I am asking.
73 1.7 with D jet .... running very rich .
Starts well cold .... flooded warm and again very rich.
I checked the fuel pressure by t-ing off the line just after the drivers side injectors.
I had a reading of 70 lbs .
The pressure regulator seemed suspect to me and was "a bit rough" .
Purchased a new one and still at 70 lbs ???
Help much appreciated . I have read the many write ups by using google but seem to be a bit lost .
thanks for any help / direction
Fuel pressure must be at 30 ponds max . The regulator is adjustable .
Check your return line for a restriction/crimp somewhere.
Is your return line plugged?
1. Make sure the gauge is calibrated.
2. Like James has said...make sure the return line is not plugged. Jeff Bowlsby has a great diagram on his web site and has posted it here before.
3. Fuel pressure for stock D-jet is 30-32 lbs.
4. Once the fuel pressure is sorted, check the MPS by vacuum check. Harbor Frieght has a "good enough" gauge if you don't have a good gauge with an indicator. Needs to hold at least 15 lbs. vacuum for at least 5 mins. There is a spec for it, I've forgot exactly, but it is somewhere around there.
Report back once you've done these things.
Whoops....one other thing after you check the MPS diaphram.
Make sure your injectors are not stuck open.
You can have them cleaned and flow checked by someone like Witchunter for about 50 bucks or so.
Thanks guys ...
Yes I do have a book, and know to try to hit 30 lbs.
I will check the return line.
I checked every fuel line in the engine bay today .. removed clamps section by section and all were clear.
Am I correct the return is from Fuel pump back to tank ?
If so ... to be %100 sure of being clear is it a removal of tank or can i shoot air through the line ?
Added Jeff's site to my "914 bookmarks"
We like photos...show us what you have.
this is what my schematic looks like
Attached image(s)
the single feed line
Attached image(s)
& the "Y"
Attached image(s)
That explains the high pressure. You need a return line to the tank.
Keith
Thanks ... this is odd . just purchased the car from a well known 914 guy . ... car sat for a while .
I am wondering if someone monkeyed with it . & thats why it sat .
I am running on 70 lbs pressure .
I will jack up and see what silly things are at the fuel pump .
Hopefully just correctly re- route the lines .
Thanks (i'll keep you posted ... I just knew I wasn't THAT crazy
Well, if you have a more modern replacement fuel pump, you would not have a need for the y fitting, but you will still need a return line to the tank.
Sorry to say, but you need to buy a line from Tangering, buy both, and replace them to the tank.
the following is how I installed the stainless steel lines (green) from tangerine...
when I posted this over a year ago, and asked for a critique, no one responded..
I still do not understand the "Y" and how that works. ????
blue is return line..
tks
randal
I'd say you've been nothing short of lucky to this point; Andy is 100% correct. Please don't drive the car until you redo the fuel lines completely and get rid of that nylon line... I'm sure that thing is as brittle as hell, mine looked rather like that and snapped when I bent it.
Best thing you can do for your car at this point.
That's a correct install, nothing else to comment on.
From what I recall when shopping for a pump last time the stock inline pumps are rated at 65-70 psi.
THANKS !
I re-routed the new lines ( almost everywhere) and installed the "Y" as in the above pics (at the fuel pump) ....
29 lbs !
Wow ... Smooth . Idles . Got power .
Super happy . Thanks to all for information.
I hope to be able to return the favor here.
Now ... Very motivated to work on smaller stuff .
Attached thumbnail(s)
never mind the below, as i missed the following "The Y is used to route the overflow fuel from both the pressure regulator and the fuel pump back into the tank."
thank you, i kind of understand now. something inside the pump allows for
fuel to be routed out into the return line under pressure so the return from the
fuel injector loop combined with the fuel pump pressures the fuel to move to
where there is no pressure, and back to the fuel tank the fuel goes.
tks
what i did not understand was how the Y worked in that
the fuel is under pressure returning from the fuel injector loop and then it
comes to a Y .... is the short piece also under pressure from the fuel pump ?
seems like they would be at odds with each other.. as where does the fuel
pump obtain a continued source of fuel to send down stream to the fuel tank?
obviously i do not understand how this works.
tks
randal
And off to Cars & Coffee today ... was fun to drive it .
Attached image(s)
Confess,
What type of line did you run through the tunnel?
What was the situation at the tank with no line on it from the previous setup?
He is attending the bbq aforementioned.
The PO or P - PO had been in there .
Lines at the tank through the tunnel were new (that triple layer FI hose).
The return line was there, it had just been routed to the return port on the pump only.
And the "upper part" of the system ad just been routed incorrectly.
Danger Will Robinson...!
Rubber fuel lines through the tunnel are a problem waiting to happen. Advise replacing with the SS tubing for safety.
^^^
thanks & understand .
I just needed to know I didn't have a BIGGER issue.
Now that it runs and pressures are correct and i have been able to test other components .
My winter project(1 of them) will be to do SS lines
Thanks again to all for info !
Powered by Invision Power Board (http://www.invisionboard.com)
© Invision Power Services (http://www.invisionpower.com)