Engine having shut off problems after carb change

Discussion in '8-valve' started by bobonthejob, Jul 1, 2019.

  1. bobonthejob New Member

    Joined:
    Jun 9, 2019
    Likes Received:
    3
    hello

    My golf mk2 1.6 ez is having problems when shutting off engine when warm. The problem is that I broke the nipple on the non return valve that connects the distributor vacuum line. I have tried to block it off with some glue and tape, but that doesnt seem to work. It sounds like the engine is still rotating and then a steam sound comes, when i turn the engine off. I have just changed from pierburg to Weber 32/34 together with a 4-2-1 manifold and full stainless steel exhaust.

    So my best guess is to buy a new non return valve or do you guys have some good ideas?
     
  2. GVK

    GVK Paid Member Paid Member

    Joined:
    Oct 23, 2003
    Likes Received:
    691
    Location:
    Lincs.
    Fix the obvious fault

    engine must be idling fast at the moment for it to 'run on'
     
  3. bobonthejob New Member

    Joined:
    Jun 9, 2019
    Likes Received:
    3
    Thanks for the answer, went to a scrapyard and found a non return valve in good condition and that fixed the roughness off the engine, but the idle is still way too high and its still doing ‘run on’, so I will try to see if the mixture screw is too rich.
     
  4. GVK

    GVK Paid Member Paid Member

    Joined:
    Oct 23, 2003
    Likes Received:
    691
    Location:
    Lincs.
    Sounds like the idle needs setting up.

    Make sure the choke is going off too.
     
  5. bobonthejob New Member

    Joined:
    Jun 9, 2019
    Likes Received:
    3
    Could an air leak around the carb and intake manifold cause a higher idle speed? I will try tuning the carb tomorrow.

    Im pretty new to wrenching on cars since this is my first car ever, so everything is a first time for me and I really appreciate the help.
     
  6. GVK

    GVK Paid Member Paid Member

    Joined:
    Oct 23, 2003
    Likes Received:
    691
    Location:
    Lincs.
    Yes an air leak could cause it, spray some WD40 around the carb base with it running, if the engine note changes you have a leak.
     
  7. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    rubber flange would be a suspect, need to take the carb and adaptor plate off again though. when putting back together with a new one make sure you use the original airbox and mount it securely with the metal steady bracket on the front to the engien block. otherwise the carb flaps all over the place and soon kills your new flange.

    Just to double check with the weber carb all the old 2e2 vacuum lines go in the bin including the green ball. all you need is 1 vacuum line from the brake servo hose pipe to the distributor and it doesn't have any valves in it, 2nd nipple on the servo pipe is blocked.
     
  8. bobonthejob New Member

    Joined:
    Jun 9, 2019
    Likes Received:
    3
    Im using a new ITG airfilter with different mounting bracket and since i dont use the old airbox, I blocked the vacuum on the back of the carb that runs from carb to airbox.

    There is a second valve on the distributor line, that was connected, so i will see what happens with that removed and just run the line without the small valve.

    I will check the rubber flange for any leaks and one thing to note is that I had to remove the intake when I fitted the new exhaust manifold and I just reused the old intake manifold gasket, because i didnt have a new gasket.
     
  9. bobonthejob New Member

    Joined:
    Jun 9, 2019
    Likes Received:
    3
    Sorry for double post, but I just wanna let you know that I fixed the idle issue.

    It turns out that the accelerator cable was getting pushed by the carb, which in turn moves the throttle just a little bit, so the idle rises.

    The solution was to just cut a small piece of the tip off from the accelerator cable tip. The car runs perfect now.
     
  10. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    ah yeah, i have seen some cables with an extra long tip. good it was an easy fix :)
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice