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Thread: xflow not runing properlly

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    Bodger

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    xflow not runing properlly

    My 1300 xflow has a bcf2 and a weber 32/36. I can not idle with the speed screw at 1.5 turns it is more like 3 turns, It is already opening the progression hole, I have checked for vaccum leaks around the carb but I can't find any. Even with a larger idle jet (55) the mixture screw is more than 2 turns out. The idle is rought and while driving it exitates a bit when acelerating (i think this is a diferent problem that has to do with the jets not being the proper ones).
    Maybe the idle circuit is busted, but I have already checked for blocked jets, and they aren't ...?????? what do you think?

    I am runing a non vacuum eletronic distributor. I think I should be using a vacuum distriutor, but meanwhile I was wondering how many degrees of advance at idle should I get? It runs better at like 16+ degrees at idle wich i think is too much, although the engine doesn't seem to ping.
    what I am more puzzled about is that when idling I don´t seem to have any vacuum at all on the carb advance port, only when I acelerate a bit, shouldn't it have vacuum when idling and stop when throttle is applied?
    I think all these problems are linked, but i don't know where to start.

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    Bodger

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    Re: xflow not runing properlly

    And I forget to mention that sometimes when it seats for a couple of days, it takes a lot of cranks to start, and when it does that and finally starts I need to keep my foot on the acelerator a bit so it doesn´t die.
    It is a manual choke and I would like to know how to set the high speed idle, I think that might be the problem...

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    World Champion Decade Plus User alladdin's Avatar

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    xflow not runing properlly

    Have you checked cam timing ? Did you build it yourself and Has it always been like this ?


    Sent from my iPhone using Tapatalk

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    Spanner Monkey Mkdu's Avatar

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    Re: xflow not runing properlly

    If you have the opportunity, try another carb,
    I ran a 1600 xflow with same cam bcf2, had to put a lot of advance at idle, around 15.

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    Bodger

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    Re: xflow not runing properlly

    Quote Originally Posted by alladdin View Post
    Have you checked cam timing ? Did you build it yourself and Has it always been like this ?


    Sent from my iPhone using Tapatalk
    The engine was built by me. It was even worst so then I rechecked cam timing and it was retarded, now it is set to the correct value, it got a bit better but the problem at idle remains.

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    Bodger

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    Re: xflow not runing properlly

    Quote Originally Posted by Mkdu View Post
    If you have the opportunity, try another carb,
    I ran a 1600 xflow with same cam bcf2, had to put a lot of advance at idle, around 15.
    but those 15º are with a vacuum distributor right?
    I think the vacuum advances the timing when idling am I right??? the thing is that I only have a bit of vacuum on the port when I give it some throtle.
    Last edited by carmos; 29-06-2018 at 12:01.

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    Re: xflow not runing properlly

    No, when idling the vacuum advance does nothing as the vacuum take-off port is just above the throttle plate when idling, so no vacuum to distributor.

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    Bodger

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    Re: xflow not runing properlly

    oh ok thanks.
    Is it normal that when I set the timing strobe light to 14º or other figure, with the engine runing, the mark on pulley is all over the place, but if I set the strobe to 0º the mark on pulley stays still? This makes the timing a bit hard to set

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    Re: xflow not runing properlly

    Quote Originally Posted by carmos View Post
    oh ok thanks.
    Is it normal that when I set the timing strobe light to 14º or other figure, with the engine runing, the mark on pulley is all over the place, but if I set the strobe to 0º the mark on pulley stays still? This makes the timing a bit hard to set
    Possibly a broken spring on the mechanical advance in the dizzy so advance isn't fully controlled?

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    Bodger

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    Re: xflow not runing properlly

    Quote Originally Posted by katana View Post
    Possibly a broken spring on the mechanical advance in the dizzy so advance isn't fully controlled?
    I don´t think so, because with the engine runing at the same speed with the strobe set to fire at 0º advance the mark on the pulley stays still and if I dial some advance on the timing light the mark is all over the place.

    The thing is that with the strobe set to fire at 0º advance I don't know where is 14 or 15º because the block only has a 12º mark

    I think I have to try with another timing light

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    Spanner Monkey Mkdu's Avatar

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    Re: xflow not runing properlly

    you need to find the true 0, like dialing the cam, don't trust the pulley if you don't sure of the real TDC.
    Then with a good timing light, you can set the advance on the light, and check with your mark on the pulley,

    mine was without vacum, was a programmable one, so I was able to adjust the curve
    Last edited by Mkdu; 01-07-2018 at 12:07.

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    Re: xflow not runing properlly

    Just a question:
    The idle speed is to low with the idle speed screw at 1.5 turns in (not exposing the progression hole). I need to turn it like 3 turns to get a good idle (1000 rmp), exposing the progresion hole a lot, and making a flat spot on the begging of aceleration. Should I try drill a 1mm hole on the throttle plate? I think I read that somewhere.
    I have a spare one, so id it doesn't work I can allways swap them.
    What do you think?

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    Bodger

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    Re: xflow not runing properlly

    Just a question:
    The idle speed is to low with the idle speed screw at 1.5 turns in (not exposing the progression hole). I need to turn it like 3 turns to get a good idle (1000 rmp), exposing the progresion hole a lot, and making a flat spot on the begging of aceleration. Should I try drill a 1mm hole on the throttle plate? I think I read that somewhere.
    I have a spare one, so id it doesn't work I can allways swap them.
    What do you think?

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