Air leaks should lower the idle speed, since the standard tuning method
pretty-well results in the highest idle speed possible for a given throttle
opening. Sounds more like there is a problem with the adjustment of the
linkages or throttle cable/pedal stop, or possibly you have a damaged
butterfly, which is preventing one or both butterflies fully closing. You
should be able to adjust the idle speed right down so it won't run at all.
PaulH.
----- Original Message -----
From: Phillips, Frank <fwp@ufl.edu>
To: <mgs@autox.team.net>
Sent: Friday, October 13, 2000 6:38 PM
Subject: High RPM
> List,
>
> Drove my B to work today and am still fighting a high idle speed. I've run
a
> wire to the cockpit and now have the dwell/tach meter plugged in so I can
> see what is truly happening, the cars tach reads high. My idle varies but
is
> mainly high. Idles around 1500-1600 RPM when it should be 900 - 1000 (1968
> MGB, AUD-265's). I feel there are air leaks in the carb's. What is the
best
> (or any) way to check for leaks? Where else should be checked? I rebuilt
the
> rest of the carbs about a month (6 weeks?) ago and they seem to function
> well. The car runs great as long as you don't intend on stopping, high
idle,
> runs on... The running on is due to the high idle...
>
> On another note... I have fitted a mechanical oil pressure gauge in-line
> with the old electronic one still in place. Oil pressure is great! The old
> gauge tends to drop to zero at idle once the car gets hot, new gauge read
> about 20 - 25 psi. The old also read 5-15 below the new. Cool!
>
> Frank Phillips
> Campus Planning and Construction Management
> Email: fwp@ufl.edu
> http://plaza.ufl.edu/fwp/mgb.htm
>
>
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