Fuel leak on holiday - urgent!

Discussion in 'Mech Tech' started by dazzaxjr, Aug 24, 2011.

  1. Here's one last picture of the empi type pump fitted in France.
    [​IMG]

    You can see the discolouration on the case. Looks like it really cooked!

    At least it got us most of the way home. 800kms out of 1200kms. Now it can rest on a dusty shelf in the garage. :)
     
  2. That's really wrong!
    Were they both like that?
     
  3. Are you putting the tie straight to the fuel line? I'd have wanted a piece of cut pipe or something between to prevent chafing.
     
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  6. OK, really interesting. Just spoke to a mechanic about getting van booked in for a number of jobs, and got talking about fuel pump relay problems.

    Previously I'd wired up the relay to the coil +ve and -ve, but this caused problems with van breaking down and not going over 40-50mph. He said I should connect to coil +ve and chassis for -ve instead.

    Apparently the coil -ve is not constant and pulses (or was it the electronic ignition) and this is likely causing the problems.

    Will try this layout tomorrow and see what happens. If it works then I can wire up the relay again so that pump goes on and off with ignition via relay connecting power to battery. Luvverly jubbly. :)
     
  7. That'll do it ^-^
    On the FI relay I posted the sensor wire goes to the coil negative ie the 'pulsed side'. Long as the relay recieves a pulse within a second or so it runs the pump. That relay has a built in fuse for the battery feed to the pump as well. I really think it's the neatest solution.
    Cheers
    s
     
  8. I'm using a very basic relay, not an FI one. So I think this pulsed connection was switching the relay off/on and therefore the pumps power. This is likely causing the issues.

    My setup i think will be simpler that yours as I'll only be using the coils +ve to switch on the pump with the ignition. It'll save me keep having to switch manually whenever I start or stop in the van. :)
     
  9. Ok just to bring some closure to this thread (and my problems) heres how things got fixed!

    Redid the cabling on my cb performance fuel pump to put the relay back into the circuit so that pump goes on and off with the ignition like this:
    [​IMG]

    Pump runs well, and importantly doesn't seem to get hot like some of the others. When I first ran it it was still having problems. Running rough and missing. I managed to find a local mechanic who found a small piece of rubber in one of the carbs. Must have been left in one of the fuel lines on one of my numerous attempts to install fuel pumps. On the way back did a couple of miles on the motorway and the motor spun up to 65-79mph as sweet as you like.

    I am a very happy man. :D

    So with the benefit of hindsight here's what most likely happened.

    1) first the mechanical fuel pump started leaking fuel.
    2) square empi pump fitted by French garage, ran fine for a while but overheated and cut out causing engine to completely die. Most likely faulty as ran ok for a while when given a chance to cool down.
    3) two pumps shipped from UK. First definitely faulty, second could be faulty or perhaps not getting enough power as I'd cable +ve and -ve to the coil. At this stage as well dirt could have got into the carbs as I'd removed and installed all fuel lines and different pumps a number of times.
    4) fitted cb performance pump when I got home, it ran ok and ran cool but engine seemed to lose power occasionally but did run without dying completely like the empi pump. At this stage mechanic found dirt/rubber in carb. Also recabled power using relay as above and no -ve connection to the coil. ;)

    So with hindsight had a couple of different issues, but all related to pump or fitting of pump and allowing dirt into carbs. Bad pumps, and need to be more careful fitting in future. Although hopefully the new pump will last a long time.

    Cheers everyone. Karma on it's way. :)
     
  10. It's disturbing how many of the pumps were faulty. So much for quality control!
    Glad you're OK now..
    Have Fun O0
    s
     

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