Broke Down Today, Ignition Problem, Accuspark Potential Cause

Discussion in 'Mech Tech' started by chrisselby, Apr 19, 2017.

  1. Pertronix for the win!!!!!!!

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    mgbman and Dubs like this.
  2. Next its proper vac dizzy time I would say, as @Dubs says that will probably sort out the lumpiness

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    Dubs likes this.
  3. 009 was on the bus when I bought it mate and this lumpy/jumpyness wasn't there on the standard carb. I had a flat spot in second, but the acts have gotten rid of that.

    carbs and linkage all balanced.

    does the idle circuit come into it, I thought that the idles cut off assign as you touch the throttle?

    could I tweak the idle screw on the carbs?

    im running

    Genuine Weber 34 icts
    F6 emulsions
    150 needles
    165 air correctors
    55 idles
    135 mains.

    not sure if this is related, but I poked my head in the engine bay after my trip, and noticed the right hand carb (drivers side) was really cold, and had some condensation formed, whereas the left hand one was Luke warm with no condensation?

  4. got a feeling that it would have been fixed with points or another accuspark, but how long it would have lasted I do not know.

    lets hope the 30 month warranty on the pertronix is a sight of good times.

    as above, the lumpiness seems to have occurred since the icts have gone on :(
  5. Hmmm. That does seem to indicate misfiring.
  6. Dubs

    Dubs Sponsor

    The idle air screws only effect idle running, they won't effect driving. The idle jets effect up to roughly 2000 rpm.

    The one side colder than the other must be a clue... I know you have said they are balanced, but have you had a snail gauge on them to check? It does sound like one side is burning fuel better than the other.

    Assume you have set the tappets and plug gaps?
    snotty likes this.
  7. tappets were done, had a sync-meter on them but will check them again.

    will check the plugs gaps as well.

    could the side that is colder be causing the lumpy running?
  8. Mine was the same until I fitted 140 mains, no idea why and that was with a vac advance.

    Assume you have a balance pipe?
  9. what did the plugs look like, same colour, nice chocolate brown.
  10. re check the air flow with your snail meter. They need to be within 10% of each other. The mixture screws should be almost the same. Check you have defo got a spark on 1 and 2.
  11. I have just replaced the spark plugs back to a set of Bosch ones.
    I bought some accuspark ones when I bought the last module, but on comparing the accuspark ones to the Bosch the accuspark ones do seem to sit really far into the combustion chamber.
    they have some out quite great aswell, plus the caps which the plugs click onto would not stay tight.

    will give it a drive tomorrow.

    replaced the dizzy cap and rotor arm for beru ones, much better quality.

    yes got a balance pipe.

    140 mains, what do you think @earlylatebay

    see above.....
  12. Also it should run fine with the 55 idles. and the 135 mains. Yes some people go to 140 mains but it should operate on the idle circuit fine. For whatever reason it is obviously not firing on 1 and 2. How does it sound on tick over.

    Check for a spark. does the idle drop when you remove number 2 plug, (1 is hard to get to with the carbs). Get it running and then pull off No 1. If you cant quickly get it back on then stop the engine and put it back on.

    If it is idling well you should get a significant drop in idle speed as you take one plug off.
  13. 140 mains are what I run but I also have a 110 cam. Having said this it should run OK on 135's and many people run 135's with a standard cam. For what they cost you can try them and see. As you have 165 airs, 140's mains might make a better balance. I have 140's with 160 airs.
  14. As has been said, the 009 is not ideal for a bus as it does not help the ignition to advance as the bus pulls its weight about. It should not misfire though.

    Are you sure the idle circuit on the RH carb is free of blockages. what fuel pressure are you running? this is crucial with the ICT's. It must not be over 3.5 psi. They will not let it fire if it is over fuelling or if it is fuel starved on the RH carb.
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  15. will check this, it seems to drive and idle fine, doesn't sound like its not firing on 1 and 2, but are you saying its not?

    i will check the balance

    i am running the standard fuel pump, no regulator.
  16. Not saying its not idling on all 4 just worth a check. It may be over fuelling. When I fitted my ICT's I had running issues. It was all down to fuel pressure. I fitted a regulator. Set the pressure to 2.5 psi and all sorted. Your mates garage should have a fuel pressure gauge. The standard pump can deliver upto 6 psi. This is far too much for the ICT's and they will over fuel, stopping the van from firing. My standard pump was pushing out between 5 and 6 psi.

    You don't need a fancy regulator but you probably will need one. but before you buy one check the fuel pressure.
    Dubs likes this.

  17. ok will check.
    could that also be why its lumpy just cruising along if its over fueling?
  18. Possibly.
  19. You set with a snail gauge, so initial balance is bob on (or should be!)

    How have you checked they open at exactly the same rate? I had fun setting up a set of HPMX's (the cheap empi ones) as they opened at slightly different rates. Lots of fiddling to get both arms identical ensued.

    Easy check, do they both reach fully open at exactly the same point?
  20. @earlylatebay @snotty @pkrboo @Dubs

    if i was to go for an svda distributor, which would be best to buy, a pertronix one which is around £170, or an svda with points and retro fit the pertronix module?
    bit wary of reports of the distributors being poor chinese units

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