Diesel In Distress - Support Ticket Need Help ? Broke Down Or in Urgent Need Of Assistance Post Here , Thread Will Be Priority and You have the ability to close your own thread when its fixed . If You Do Not Reply in 10 Days your thread will be closed as we will assume its fixed , You can Reopen YOUR Discussion Topic if you wish .

fuel problem, cummins

Thread Tools
 
Search this Thread
 
  #1  
Old 02-15-2010, 01:13 AM
zach_west's Avatar
Diesel Wrench
Thread Starter
Join Date: Jan 2009
Location: Canyon, Tx
Posts: 977
Received 33 Likes on 25 Posts
Default fuel problem, cummins

I have a 96 dodge with the p-pump. well i've been noticing lately that if you try to keep a constant speed at above 65 it starts to shake and sputter until you back down under 65 then runs strong. and when i shift through the gears i'm not lacking for fuel and it's not smoking white just black. i haven't been able to find a fuel leak until today when i noticed fuel coming from my injector cup. I was wondering if i could just tighten that up and be ok or do i need to do something else. i really need some help on this one soon as i don't like the fact of a fuel leak that close to my exhaust. especially since i have to drive it at least 50 miles a day to work and all. thank ya'll Zach West.

---AutoMerged DoublePost---

also the fuel is leaking 4 out of the 6 injectors. this problem didnt start until i put a different injection pump in either. there is no other fuel leaks in the system.
 

Last edited by zach_west; 02-15-2010 at 01:13 AM. Reason: Automerged Doublepost
  #2  
Old 02-15-2010, 03:02 AM
9412Valve's Avatar
Diesel Enthusiast
Join Date: Mar 2009
Location: Okinawa, Japan
Posts: 240
Received 10 Likes on 10 Posts
Default

Did you make sure and tighten all the lines correctly?
 
  #3  
Old 02-15-2010, 08:17 AM
zach_west's Avatar
Diesel Wrench
Thread Starter
Join Date: Jan 2009
Location: Canyon, Tx
Posts: 977
Received 33 Likes on 25 Posts
Default

ya i loosened them and made sure they were all straight and seated and they are. my brother thought that it might be the return lines but its not they are all tight and not leaking any
 
  #4  
Old 02-15-2010, 08:48 AM
Dr. Evil's Avatar
BOMBARDIER
Join Date: Mar 2007
Location: North of You
Posts: 23,293
Received 1,322 Likes on 1,071 Posts
Default

This could be part of the problem - have you ever replaced your rubber fuel lines? Just because it isnt leaking doesnt mean you dont have a leak. The fuel line develops very tiny holes that are small enough to let air in and not let fuel out. Do not use regular gas rated hose.
 
  #5  
Old 02-15-2010, 09:45 AM
Diesel Nut's Avatar
Diesel Bombers Sponsor
Join Date: Jun 2007
Location: Sacramento
Posts: 1,321
Received 109 Likes on 87 Posts
Default

Dr. Evil is correct. Those lines are notorious.

The next thing I would ask is how long since the fuel filter what changed?

Do you have the ability to check fuel pressure?

You say none of these problems came about until after installing a new P7100. Did you replace the overflow valve on the pump with a new one or did you reuse the old one?
 
  #6  
Old 02-15-2010, 12:42 PM
zach_west's Avatar
Diesel Wrench
Thread Starter
Join Date: Jan 2009
Location: Canyon, Tx
Posts: 977
Received 33 Likes on 25 Posts
Default

i reused all of them i asked my brother he said the copper washers on the return lines might have gone lost their spring. i tightened the bolts and 2 of them stopped leaking i was wondering if this could be part of the problem. and the fuel filter was changed bout 1000 miles ago when i changed my oil after the pump change. and i can check the fuel pressure at the shop at my college.
 
  #7  
Old 02-15-2010, 02:00 PM
Dr. Evil's Avatar
BOMBARDIER
Join Date: Mar 2007
Location: North of You
Posts: 23,293
Received 1,322 Likes on 1,071 Posts
Default

Never reuse the copper washers - they are cheap enough to replace every time.

To check fuel pressure you need to tap the bano bolt on the inlet of the P-7100. Use a 1/8" tap and an R drill bit - its should look something like this (dont forget to install a needle valve to act as a pressure snubber):

Name:  25501mvc-016f.jpg
Views: 18
Size:  15.8 KB
 

Last edited by Dr. Evil; 02-15-2010 at 02:04 PM.
  #8  
Old 02-15-2010, 02:19 PM
zach_west's Avatar
Diesel Wrench
Thread Starter
Join Date: Jan 2009
Location: Canyon, Tx
Posts: 977
Received 33 Likes on 25 Posts
Default

i never took them off i guess they haven't been changed in a while and thank you for the pic. what fuel pressure should i have there?
 
  #9  
Old 02-15-2010, 02:21 PM
Dr. Evil's Avatar
BOMBARDIER
Join Date: Mar 2007
Location: North of You
Posts: 23,293
Received 1,322 Likes on 1,071 Posts
Default

22-25 psi at idle and just over 30 at WOT.
 
  #10  
Old 02-16-2010, 12:31 AM
zach_west's Avatar
Diesel Wrench
Thread Starter
Join Date: Jan 2009
Location: Canyon, Tx
Posts: 977
Received 33 Likes on 25 Posts
Default

alright thank ya i'll get that checked out in class tomorrow we have fuel systems anyways
 


Quick Reply: fuel problem, cummins



All times are GMT -5. The time now is 09:13 AM.