Low idle too Low

[Inverted]

Hi all,

Slight conundrum i wonder if someone can help. I've been starting Ivy up over the last few cold months whilst she's tucked away for the winter, to keep things moving. She starts first time everytime, with the choke out, however, even with the choke pulled out at varying positions she still stops running unless i have a bit of pressure on the accelerator. If i pull the choke out fully it also stops the engine rather quickly. So i am finding it hard to find the balance between the carb and choke...
Would adjusting the carb fix the problem? as when she's warm she idles brilliantly...
Chris

[bmcecosse]

Yes - there is a separate screw that increases the engine speed with the choke pulled. Just tweak it up slightly - if you look closely at the carb while someone pulls the choke it's very obvious. I hope each time you start the engine - you bring it up to full warmth otherwise you may be building up problems .

[MarkyB]

Sounds more or less perfect to me, you are getting to know the character of your car.
You just push the choke in progressively as the car warms up, it isn't automatic or an on off switch.

[Inverted]

Thanks for the replies....

yep she's always run for 20 mins or so so should be fine. I'll have a tweak about with the carb and see if it helps. I think i may have been a little vague in my description of the problem. The main issue, is that even with the choke, i'm needing to up the revs with the accelerator. I do progressively move the choke in as she warms up, however it takes a while before she'll sit there by herself with no input from me. If anything the choke seems to work too well, in the fact that even the slightest application seems to "choke" the engine to a stop....

thanks again

Chris

[bmcecosse]

And that's exactly what the second throttle stop screw - that only works when the choke is in use - is for!

[mike.perry]

There are two adjuster screws with springs around them.
One screw acts on a stop, if you turn it clockwise it will speed the engine revs and vise versa.
The other screw acts on a cam and should be set so that with the choke in it just touches the cam. When the choke is pulled out the cam lifts the screw and increases the tickover speed whilst the engine is warming up

[Inverted]

Thanks a lot that helps greatly
Thanks for the explanation Mike, i really am still very much on the learning curve still having never had to work with an engine before....

Regards
Chris

[Inverted]

Been out to have a look at the carb... was relly easy to fix.
All it was in the end was a build up of grease and muck that was hindering the the screw to return to just sit on the cam. All fully cleaned and oiled and working beautifully. Goes to show the engine needs just as much to be kept clean as the bodywork...
I love it when its a simple fix...

[xpress]

hi, where are the adjuster screws located? thanks.

[Declan_Burns]

hi, where are the adjuster screws located? thanks.

You can see them on this photo.
As Mike has explained....
There are two adjuster screws with springs around them.
One screw acts on a stop, if you turn it clockwise it will speed the engine revs and vise versa.
Marked "A"

The other screw acts on a cam and should be set so that with the choke in it just touches the cam. When the choke is pulled out the cam lifts the screw and increases the tickover speed whilst the engine is warming up
Marked "B"[frame][/frame]


Regards
Declan

[xpress]

what should the idle be? i put a tach on the 1st plug ht lead and i got roughly arond 750 rpm, seems way high. i have a bit of a flappy idle note that wavers a tad, tho. any ideas on how to smooth this out? regards.

[katy]

Idle should be around 500-550 RPM. Typically a loping idle is caused by incorrect mixture, usually, but not necessarily, too rich.

[bmcecosse]

Both mixture and timing affect the idle - twiddle them both a little bit at a time to get the smoothest idle. Make sure the vacuum advance is connected up - and is working as it should! Suck the pipe and watch to see the baseplate in the dizzy advance and retreat as you suck and let go.