Electric fuel pump died/overheated... why? - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep CJ Forum > Electric fuel pump died/overheated... why?

ROCKRIDGE4WD Introduces a NEW Jeep Wrangler JK *led* tail Spartan Locker Promo Running now @ ROCKRIDGE 4WD plus FREERough Country Lift Kits and Parts!

Reply
Unread 09-30-2007, 07:28 PM   #1
part.changer
Registered User
1976 CJ7 
 
Join Date: Apr 2007
Location: Dirty South
Posts: 402
Electric fuel pump died/overheated... why?

Is it possible that running an electric fuel pump on very low fuel could burn the motor up?

If so, would a mechanical fuel pump be susceptible to the same problem? I think I'm going to go mechanical.

Any mechanical recs other than standard (76 CJ7 304)?

part.changer is offline   Reply With Quote Quick reply to this message
Unread 09-30-2007, 07:39 PM   #2
Chrisfol82
Registered User
 
Join Date: Aug 2006
Location: Pittsburgh, Pa
Posts: 326
If you had it plumbed in wrong maybe that coudl be the problem. Did you ahve a return line?
Chrisfol82 is offline   Reply With Quote Quick reply to this message
Unread 09-30-2007, 07:47 PM   #3
Fatman
Registered User
2008 CJ7 
 
Join Date: May 2006
Location: Raleigh, NC
Posts: 2,434
Electrics don't last forever.
For mechanical look at Accel or Holley, they're not cheep.
__________________
Fatman is offline   Reply With Quote Quick reply to this message
Unread 09-30-2007, 07:53 PM   #4
scotts81cj7
Registered User
 
Join Date: Jan 2007
Location: kamloops bc canada
Posts: 38
electric fuel pumps use the fuel in the tank to keep cool...
scotts81cj7 is offline   Reply With Quote Quick reply to this message
Unread 10-01-2007, 02:39 AM   #5
soccerpapa
Registered User
1980 CJ7 
 
Join Date: Jun 2007
Location: Utah
Posts: 143
Hey P.C. good to see you still working on that Jeep...

I recently replaced my mech with an electric pump (Holley Red), and when I tested it I found that if I did not run a return line, the pump was seriously overheating and appeared to be boiling the fuel. When I re-installed the return line, it ran as cool as ice... I would figure that running the pump dry or low fuel conditions would overheat the sucker as well. I love the electic pump performance, but I HATE the noise... If given the choice again, I would go with a high grade mechanical pump over the electric. Best to you...
__________________
Mama Says... Jeeps are the Devil!
***1980 Jeep CJ7 Laredo, 304 V8***
soccerpapa is offline   Reply With Quote Quick reply to this message
Unread 10-01-2007, 08:25 AM   #6
part.changer
Registered User
1976 CJ7 
 
Join Date: Apr 2007
Location: Dirty South
Posts: 402
I don't know about any return line on this pump. It's a pretty simple device... one in from the tank... one out to the engine. Am I missing something here?
part.changer is offline   Reply With Quote Quick reply to this message
Unread 10-01-2007, 08:37 AM   #7
fuzz401
Registered User
1978 CJ7 
 
Join Date: Jan 2003
Location: Lancaster, Pa.
Posts: 1,758
a good mechanical pump look at a carter super pump what I use
__________________
1978 cj-7 had since 1979
401 .030 over- full floating flat top pistons
crower solid cam 292 dur .500/.510 lift
turbo 400 tranny 2500 stall
model 20 transfer case
aj delux glass body
4" lift
dana 30 frount
dana 44 rear
4.56 gears
http://img2.photobucket.com/albums/v...slideshow=true
http://photobucket.com/albums/v31/fu...slideshow=true
13.461 @ 92.45 mph on 37" super swampers on 1/4 mile
fuzz401 is offline   Reply With Quote Quick reply to this message
Unread 10-01-2007, 01:35 PM   #8
soccerpapa
Registered User
1980 CJ7 
 
Join Date: Jun 2007
Location: Utah
Posts: 143
You are missing the fuel filter... installed after the pump and prior to the carb. The stock filter has a return line (1/4") that goes back to the tank for recycling. This keeps fuel flowing through the pump (since it never stops running) when your carb bowls are full (floats should stop flow). Otherwise, the pump and fuel overheats and causes the pump to fail or the fuel to boil (vapor lock). I have tested and verified that this does occur without a return line.

However if you are going to replace the pump, I would take fuzz401's advice and go mechanical. Either way, you will still need a return line to prevent vapor lock.
__________________
Mama Says... Jeeps are the Devil!
***1980 Jeep CJ7 Laredo, 304 V8***
soccerpapa is offline   Reply With Quote Quick reply to this message
Unread 10-01-2007, 10:17 PM   #9
Chrisfol82
Registered User
 
Join Date: Aug 2006
Location: Pittsburgh, Pa
Posts: 326
With an electric pump you definately need a return line. That pump is going to want to pump a certain amount of fuel whether the engine needs it all or not. If your not using enough fuel youll be deadheading the pump. The fuel will basically stop flowing through the line, or going very slow at higher pressure than the pump was designed for. Obviously this is not good for the pump. By putting in a return line you allow the pump to operate within its proper curve and when the engine isnt requiring the full amount of flow from the pump, which it probably never is, it will just be recirculated back to the tank.
Chrisfol82 is offline   Reply With Quote Quick reply to this message
Unread 10-01-2007, 10:31 PM   #10
Jason790812
Registered User
1981 CJ7 
 
Join Date: Apr 2007
Location: Mississippi
Posts: 244
Yep running an electric pump low on fuel or out of fuel will burn it up sometimes. I've burnt one up in a company Ford Ranger by running it out of gas. I never would of thought it, but after replacing the pump in the tank it fired right up.
Jason790812 is offline   Reply With Quote Quick reply to this message
Unread 10-01-2007, 11:00 PM   #11
part.changer
Registered User
1976 CJ7 
 
Join Date: Apr 2007
Location: Dirty South
Posts: 402
All right... I ordered a replacement mechanical pump. Now, I still don't know where the return line will go.

The mech. pump will be up in the engine compartment near the carb, so where in the world is the return line?

(1) Will I have to run a line all the way from my engine compartment *back* to my fuel tank? (2) Does my fuel tank have an extra inlet somewhere for such a line?

ON SECOND THOUGHT: I will be installing this mechanical fuel pump from scratch and have no idea where it goes and how it's to be plumbed. (3) Anyone know of tutorials/pics? I'll have a rubber fuel line from tank to just ahead of the rear axle, a steel line up to the engine compartment (probably up to the mech. pump), then a rubber line into the carb with a fuel filter inline in that section. (4) Is that correct?

Also, as stated above, where is the return line?

(5) What other precautions should I take against vapor lock?
part.changer is offline   Reply With Quote Quick reply to this message
Unread 10-02-2007, 12:30 PM   #12
soccerpapa
Registered User
1980 CJ7 
 
Join Date: Jun 2007
Location: Utah
Posts: 143
mech pump only goes in one place on your engine.

Yes, you will have to run a line back to the tank... see other recent threads on return line for pics.

http://www.jeepforum.com/forum/f8/fuel-return-line-462220/
__________________
Mama Says... Jeeps are the Devil!
***1980 Jeep CJ7 Laredo, 304 V8***
soccerpapa is offline   Reply With Quote Quick reply to this message
Unread 10-02-2007, 12:43 PM   #13
part.changer
Registered User
1976 CJ7 
 
Join Date: Apr 2007
Location: Dirty South
Posts: 402
Perfect thread... thanks.

The line from my tank to my pump is steel tubing. Does my return line need to be steel tubing as well or can it be rubber?

TO ALL: Please address numbered questions above as well, if you'd like.
part.changer is offline   Reply With Quote Quick reply to this message
Unread 10-02-2007, 03:33 PM   #14
part.changer
Registered User
1976 CJ7 
 
Join Date: Apr 2007
Location: Dirty South
Posts: 402
^selfish bump^
part.changer is offline   Reply With Quote Quick reply to this message
Unread 10-02-2007, 04:42 PM   #15
Fatman
Registered User
2008 CJ7 
 
Join Date: May 2006
Location: Raleigh, NC
Posts: 2,434
I'd run hard stainless 5/16 from the tank to the pump, and the same along the frame for the return line.

http://www.4wd.com/

I think I paid $39 for a 20' roll.
__________________
Fatman is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.