Fuel pump? - Defender Source
Defender Source  

Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions


Reply
 
Thread Tools
  #1  
Old September 13th, 2015, 10:25 PM
EnduroPro's Avatar
EnduroPro
Status: Offline
Stephen LeBlanc
1994 Defender 90
Member
 
Join Date: Jul 2004
Location: Woodbury, CT
Posts: 533
Fuel pump?

Hi all. So my mechanic buddy has been chipping away at my 94 NAS D90

Fuel issues. So he started at the injectors (replaced), then to the ECU (replaced), then replaced the filter (obviously), then power washed the tank as it had 10 year old gummy fuel residue.

My fuel pump runs. Mechanic thinks it should be replaced as the injectors are still not getting the proper pressure. Does that make sense? I always thought a fuel pump was either ON or OFF but didn't really do much for regulating or affecting pressure. Thoughts?

Thanks in advance for what may seem like a stupid question.

PS: coincidentally I already own a replacement fuel pump which I dropped off to him tonight. Long story.
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old September 14th, 2015, 04:57 PM
EnduroPro's Avatar
EnduroPro
Status: Offline
Stephen LeBlanc
1994 Defender 90
Member
 
Join Date: Jul 2004
Location: Woodbury, CT
Posts: 533
Bump?
Reply With Quote
  #3  
Old September 14th, 2015, 08:54 PM
Jpayne's Avatar
Jpayne
Status: Offline
Jeff Payne
'83 110 3 Door
Member
 
Join Date: Aug 2009
Location: Albuquerque, NM
Posts: 1,393
Registry
Hook up a fuel pressure gauge and see what it reads.
Reply With Quote
Sponsored Links
Advertisement
 
  #4  
Old September 14th, 2015, 10:08 PM
EnduroPro's Avatar
EnduroPro
Status: Offline
Stephen LeBlanc
1994 Defender 90
Member
 
Join Date: Jul 2004
Location: Woodbury, CT
Posts: 533
Ok thanks.
Reply With Quote
  #5  
Old September 14th, 2015, 10:19 PM
cascade90's Avatar
cascade90
Status: Offline
Mason Worley
'95/NAS D90 SW #59/500
Member
 
Join Date: Apr 2013
Location: Seattle , WA USA
Posts: 134
After you check the pressure at the fuel rail. It's one of two things. High or low. High is generally the regulator. Low is generally the pump. You can chk the regulator with a hand vacuum pump. If it holds a vacuum it's good. If it won't hold at all...the diaphragm has a hole in it. If you chk psi and low then you have weak pump. You should be up around 3 bar(43 psi) to be fat and happy. You have 3 filters in the system. One on the pump(20 micron), the in-line(approx 10micron) and the final one's are in the inlet of each injector(3-4micron). At this point I need more info to push you in the best direction. Good luck with your search...
Reply With Quote
  #6  
Old September 14th, 2015, 10:21 PM
EnduroPro's Avatar
EnduroPro
Status: Offline
Stephen LeBlanc
1994 Defender 90
Member
 
Join Date: Jul 2004
Location: Woodbury, CT
Posts: 533
Awesome info. Working on it tomorrow afternoon. Update all to come. Thanks!!

------ Follow up post added September 14th, 2015 10:23 PM ------

Any likelihood that it could be the inertia switch?
Reply With Quote
  #7  
Old September 14th, 2015, 10:31 PM
cascade90's Avatar
cascade90
Status: Offline
Mason Worley
'95/NAS D90 SW #59/500
Member
 
Join Date: Apr 2013
Location: Seattle , WA USA
Posts: 134
I don't have enough info to answer that. It is just a switch. Bypass it. Jump the wires. If same issue then no. Don't throw money at it. Enough of that kind of thing goin on. Remember you'll figure out what it isn't long before you figure out what it is. Give more info tomorrow and I'll try and help you out. This is a science at best.
Reply With Quote
  #8  
Old September 14th, 2015, 10:43 PM
EnduroPro's Avatar
EnduroPro
Status: Offline
Stephen LeBlanc
1994 Defender 90
Member
 
Join Date: Jul 2004
Location: Woodbury, CT
Posts: 533
Quote:
Originally Posted by cascade90 View Post
I don't have enough info to answer that. It is just a switch. Bypass it. Jump the wires. If same issue then no. Don't throw money at it. Enough of that kind of thing goin on. Remember you'll figure out what it isn't long before you figure out what it is. Give more info tomorrow and I'll try and help you out. This is a science at best.

Awesome. Thanks so much for the guidance. More news tomorrow.
Reply With Quote
  #9  
Old September 19th, 2015, 07:22 AM
BrianKelley
Status: Offline
Brian Kelley
94 Defender 90 NAS
Member
 
Join Date: Dec 2014
Location: Westerly, RI
Posts: 14
Hey Stephen- how'd you make out with this? I'm getting closer to installing new braided SS lines on my 94 NAS, so hoping I don't run into similar issues. I have a new fuel pump ready to go. I've been checking previous threads this morning searching for some proper pics of all the different fittings for the supply and return lines, but can't find anything expect for a barely visible diagram on RN. I've taken a lot of photos when removing the old lines, but just have that fear that i'm missing something and/or fittings go back on correctly. If anyone has detailed pics of OEM fuel lines, or replacement ones, that would help me out a ton
Reply With Quote
  #10  
Old September 20th, 2015, 05:05 PM
EnduroPro's Avatar
EnduroPro
Status: Offline
Stephen LeBlanc
1994 Defender 90
Member
 
Join Date: Jul 2004
Location: Woodbury, CT
Posts: 533
Quote:
Originally Posted by BrianKelley View Post
Hey Stephen- how'd you make out with this?

Hey Bri. My mechanic buddy had this on hold for a week. Tinkering with it right now actually. Checking fuel pressure now... stay tuned. Thanks!


I'll text my buddy right now and ask for him to take some closeup photos. You have my number....text me exactly you want and I can likely get it. Happy to help.
Reply With Quote
  #11  
Old September 20th, 2015, 07:23 PM
samer0214's Avatar
samer0214
Status: Offline
Samer Hijazi
1997 P38 Vitesse
Member
 
Join Date: Apr 2013
Location: Irvine, CA
Posts: 390
Registry
Quote:
Originally Posted by BrianKelley View Post
Hey Stephen- how'd you make out with this? I'm getting closer to installing new braided SS lines on my 94 NAS, so hoping I don't run into similar issues. I have a new fuel pump ready to go. I've been checking previous threads this morning searching for some proper pics of all the different fittings for the supply and return lines, but can't find anything expect for a barely visible diagram on RN. I've taken a lot of photos when removing the old lines, but just have that fear that i'm missing something and/or fittings go back on correctly. If anyone has detailed pics of OEM fuel lines, or replacement ones, that would help me out a ton
Brian,

I'm doing a engine swap from carbs to a NAS 3.9L EFI engine and just installed new fuel lines. Here are your options from what I gathered:

1) Replace the factory lines with OEM lines from Rovers North: Very expensive >$1,000
2) Replace the factory lines with after market US made Stainless Steel replicas by Classic Tube Still expensive in my opinion @$340 each, but what you get is an exact replica of the OEM lines.
3) Replace the factory lines with rubber hose and fittings: Inelegant, cheap, no longevity
4) What I did: Had new lines with compression fittings made by a local company (in SoCal) for $350 total. They are Teflon lines, wrapped in Stainless Steel braiding, wrapped in a black plastic jacket. They are high pressure, heat resistant to 500 deg., and fairly flexible. The fuel return line is one continuous length with a small section of rubber hose at the fuel rail, and a compression fitting at the tank. The feed line is in 2 sections, so I can have a "canister type" fuel filter fitted, with different fittings as needed.

Hope that helps.
__________________
Thank you - Samer
1997 P38 Vitesse (Red)
2003 Discovery II
Defenderless, for now!
Reply With Quote
  #12  
Old September 24th, 2015, 05:09 PM
EnduroPro's Avatar
EnduroPro
Status: Offline
Stephen LeBlanc
1994 Defender 90
Member
 
Join Date: Jul 2004
Location: Woodbury, CT
Posts: 533
UPDATE: We replaced the fuel pump. My mechanic buddy checked the fuel pressure. It read 43-44 pounds. However, as we cranked the car to start, the pump shut off.


We made sure the inertia button is not the issue.


Is there a 2nd set of relays that we don't know about? We replaced the 2 relays under the interior/dash. 2 silver relays (with brown lines).


As a side test, we used starter fluid and the truck started right up and purrrred like a kitten.


What the heck???
Reply With Quote
  #13  
Old September 24th, 2015, 06:29 PM
Kevin88RRC's Avatar
Kevin88RRC
Status: Offline
Kevin Keith
1988 RRC
Member
 
Join Date: Dec 2014
Location: Portland, Maine
Posts: 1,045
Did you use the specific FP relay? That relay is different from the other silver relays.
Reply With Quote
  #14  
Old September 24th, 2015, 06:36 PM
EnduroPro's Avatar
EnduroPro
Status: Offline
Stephen LeBlanc
1994 Defender 90
Member
 
Join Date: Jul 2004
Location: Woodbury, CT
Posts: 533
Quote:
Originally Posted by Kevin88RRC View Post
Did you use the specific FP relay? That relay is different from the other silver relays.

Thanks Kevin. Not sure. Is that in the same relay cluster under the dash? I thought the fuel pump relay was one of the silver brown-line. Hmmmmm..

------ Follow up post added September 24th, 2015 06:37 PM ------

I called British Atlantic to order the relays. That's what they advised. I may have assumed the wrong ones to swap out?
Reply With Quote
  #15  
Old September 24th, 2015, 06:52 PM
Kevin88RRC's Avatar
Kevin88RRC
Status: Offline
Kevin Keith
1988 RRC
Member
 
Join Date: Dec 2014
Location: Portland, Maine
Posts: 1,045
You're probably fine if you got it from AB. I see they sell the black plastic ones now. The old silver ones had a red slash on the top and the relay base is blue (at least it is in the RRC).
Reply With Quote
  #16  
Old September 24th, 2015, 06:52 PM
EnduroPro's Avatar
EnduroPro
Status: Offline
Stephen LeBlanc
1994 Defender 90
Member
 
Join Date: Jul 2004
Location: Woodbury, CT
Posts: 533
Quote:
Originally Posted by Kevin88RRC View Post
You're probably fine if you got it from AB. I see they sell the black plastic ones now. The old silver ones had a red slash on the top and the relay base is blue (at least it is in the RRC).

Cool. Same spot? I'm referring to the center area under the dash. Thanks!
Reply With Quote
Reply

Lower Navigation
Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions

Tags
fuel

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
TD5 Fuel Pump/ pump tomaco1 For Sale - Parts 7 September 20th, 2011 09:13 PM
feed 200tdi lift pump from Facet fuel pump ? kjva Defender Technical Discussions 1 September 7th, 2011 01:55 AM
Fuel tank skid / fuel pump / Dixon-Bate Tow Jaw chris snell Smaller Projects 16 September 2nd, 2010 12:29 AM
Diesel conversion - fuel pump removal and new fuel feed jaherring Defender Technical Discussions 0 July 19th, 2010 03:06 AM
Fuel pump and fuel gauge relationship question - troubleshoting... arbik Defender Technical Discussions 1 September 19th, 2006 02:31 PM


All times are GMT -5. The time now is 11:51 PM.


Copyright