Another carb timing issue.....

Discussion in 'Fuel System & Electrics' started by 76kampa, Apr 20, 2018.

  1. 76kampa

    76kampa Active Member

    Messages:
    107
    Location:
    Perth
    And I'm going away on Sunday :/

    Struggling to get up to speed, backfiring and popping.
    So far I have:
    Reset rocker clearance to .006
    Set timing to the 8 (7.5) degrees (but won't run nicely)
    Played the the carby but nothing seems to change.... Odd
    Changed no.4 spark plug even though they are brand new NGK, pulling no.4 lead didn't seem to make much difference and now it makes a bit of change if the lead is pulled.

    Still not running better, I can't figure out what I have done, I haven't even been driving it.

    It has a new bosch coil and eBay electronic dizzy and single fake Weber.
     
  2. 76kampa

    76kampa Active Member

    Messages:
    107
    Location:
    Perth
    Yes I have the original still but I think the previous owner put a old model cap because it didn't run at all and at the time I couldn't figure it out.
     
  3. cbus

    cbus Well-Known Member

    Messages:
    10,666
    Location:
    sunshine coast
    Assume all other cylinders have a significant power drop when pulled?
     
  4. 76kampa

    76kampa Active Member

    Messages:
    107
    Location:
    Perth
    Hmmm just put the Original dizzy on :) as the ebay electronic one has the right cap on it and it runs much better, just got to take it for a spin up the road and see... (its only 9pm in WA )
     
  5. cbus

    cbus Well-Known Member

    Messages:
    10,666
    Location:
    sunshine coast
    Good start ;)
    Often the cheap electronic diddies are on a cheap base unit.
    Very inaccurate spark advance.

    Check both with a timing light for a steady reading and smooth fairly rapid advance thru revs.

    If a 009 set at 30-32 BTDC @ max advance which will be about 3500rpm.
    Run some good fuel.

    If a bit of flat spot get it nearer 32 BTDC
    Ia vac advance it shouldn't have the flat spot.
    Settle mixture.

    If still popping or sus on one side check that you don't have a leak between inlet manifold and head
     
    Last edited: Apr 21, 2018
  6. 76kampa

    76kampa Active Member

    Messages:
    107
    Location:
    Perth
    Now it wont run at all...
     
  7. cbus

    cbus Well-Known Member

    Messages:
    10,666
    Location:
    sunshine coast
    What coil are you running,?

    Thinking mismatch if you had different one for " elec ign"?
    Might have to sort what you need.

    Have points closed up?

    Mucked with carb?
     
  8. cbus

    cbus Well-Known Member

    Messages:
    10,666
    Location:
    sunshine coast
    Stick to basics and retrace what you have done.
    Don't muck with too many things st same time.

    Establish you have spark at points.
    From that, pull a plug and insert it into lead. Earth plug body.
    Have someone attempt start and check plug firing.

    Also check for wet plug, flooded.

    If you have spark then try aerostart procedure.
    Or slow depression of accelerator and wind engine with throttle open
    ( plug replaced) to clear cylinders.
    Or wait 15 min.
    Don't pump throttle.
     
  9. 76kampa

    76kampa Active Member

    Messages:
    107
    Location:
    Perth
    Right I sat there testing EVERYTHING :/ found it!

    I Still don't know why it wont run with the 009 dizzy but I found that the rotor on the ebay dizzy was stuffed, put the other one in and bam the kombi runs like a dream.....

    Now to get the 009 dizzy to run, I need new points, capacitor, rotor and cap and it should be right.

    Had a brain storm while having a shower....
    I think the 009 slipped out of the slot.....
    My dizzy bracket is a bit bent and I did have trouble getting it to go in the slot, seems to only just make it which is odd.
     
    Last edited: Apr 21, 2018
  10. cbus

    cbus Well-Known Member

    Messages:
    10,666
    Location:
    sunshine coast
    Definate possibility.
    Obviously if elec dissy working well go with it.
    Check that it gives a smooth advance and steady spark with timing light.

    Worth having a correctly timed backup with the 009.
    Are the edges worn?
    Not firmly pressed into place.?
    Clamp not positioned correctly.?
    Too much vertical play in shaft?
    Rotor not firmly in place?

    Check Ratwell on dissy rebuild.

    Roughly whenever I fit I check..
    Alignment of bottom lugs.
    Should have less than 1mm vertical play in shaft. Can repack with more shims . actual spec is less.
    Ensure no side play in shaft.
    Check earth braid connected inside dissy.
    Points still gapped correctly and screw tight.
    Drop of oil on shaft felt.
    Grease on cam area of shaft.
    Condenser connector fitted inside dissy.
    Minimal vertical play.
    Rotor firmly in place.
    Dissy firmly down into case.
    Rotate rotor/ shaft both ways plus up/ down to ensure bottom fully engaged. ( usualy has a couple mm play rotationally . don't worry)
     
  11. oldman

    oldman Super Moderator Staff Member

    Messages:
    7,776
    Location:
    Avalon Beach NSW
    Personally, long term.... I’d ditch the 009 and get what your engine should have, a vac.advance dizzy....
    Make sure the valve clearance is .006 of an inch and not mm. (Common error).
    Fake Weber in the mix ain’t gonna help running issues either.
    Assuming it’s a CJ engine, stock dizzy with matched dual carbs. wil be your best option for longevity and hassle free cruising....
    Cheers,
    Mark
     
  12. Barry

    Barry Well-Known Member

    Messages:
    2,395
    Location:
    Abbotsford NSW
    From memory you have a centre mount singe carb on a type 4.
    there is no pre heaters on that set up - so it will never idle well compared to a stock set up
     
    oldman likes this.
  13. 76kampa

    76kampa Active Member

    Messages:
    107
    Location:
    Perth
    Yes I would like a vac advance dizzy but how to get one?

    As for the twin carbs....
     
  14. oldman

    oldman Super Moderator Staff Member

    Messages:
    7,776
    Location:
    Avalon Beach NSW
    Contact Andrew - aka 1500king-
    https://www.facebook.com/VolksDoktor/
    You will be able to get everything you need built to original spec. from him....
    If he hasn’t got it, he’ll be able to advise you.
    Cheers,
    Mark
     

Share This Page