Author Topic: Rich idle....  (Read 3550 times)

1938vw

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Rich idle....
« on: 10:40, Sun 25 March 2012 »
Hey folks, I'm running a wideband afr and getting read outs of around 11-12:1 @ idle.
My two questions are:
How do I make the idle leaner?
Is it normal for the readout to go back and forth a bit?

I ask this because when I hold it at say 3000rpm it sits nicely at say 12:1 and doesn't jump around.
At idle it can go 1-1.5:1 up or down but at 3000rpm only 0.5:1 up or down.

andybond

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Re: Rich idle....
« Reply #1 on: 12:34, Sun 25 March 2012 »
You need to change the idle with the idle screw located on the offside of the carb.

Mine sometime fluctuates. Screw it in tight and then back out a little. That tends to cure it

1938vw

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Re: Rich idle....
« Reply #2 on: 12:43, Sun 25 March 2012 »
Thanks for the help ;)

1938vw

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Re: Rich idle....
« Reply #3 on: 18:43, Wed 28 March 2012 »
I've now wound the idles mixture screw all the way in and it's still running rich 11-12:1! What do I do now?

andybond

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Re: Rich idle....
« Reply #4 on: 22:02, Wed 28 March 2012 »
Wind it out !

If it didnt change the mixture then it sounds like either the needle has snapped , or the seal around the needle has failed.

1938vw

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Re: Rich idle....
« Reply #5 on: 10:14, Thu 29 March 2012 »
Will do, cheers

1938vw

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Re: Rich idle....
« Reply #6 on: 22:21, Thu 29 March 2012 »
Quote from: "andybond"
Wind it out !

If it didnt change the mixture then it sounds like either the needle has snapped , or the seal around the needle has failed.
I have removed and checked it and it seems fine, I then replaced the seal and it is much better now thanks!

One more question, when I removed the idle jet to check the size a while ago it seemed to have a rubber o ring at the top of the screw, I was wondering should this be rubber, fibre or copper as I don't seem to have a rubber o ring of that size in the rebuild kit and on a diagram I have it doesn't show anything at all?

andybond

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Re: Rich idle....
« Reply #7 on: 18:42, Fri 30 March 2012 »
It's meant to be rubber. It often goes hard and brittle mind...

1938vw

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Re: Rich idle....
« Reply #8 on: 21:39, Fri 30 March 2012 »
Quote from: "andybond"
It's meant to be rubber. It often goes hard and brittle mind...
Cheers

1938vw

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Re: Rich idle....
« Reply #9 on: 12:58, Sun 29 April 2012 »
Hey folks all sorted now, I had to drilled out the idle jet from .45 to .55 and I replaced the o ring around the jet holder and replaced to idle mixture screw and o ring.

Cheers again folks