[Mgs] Mgs Digest, Vol 62, Issue 6

[Glenn Schnittke]

Aaron,

I have to agree with Paul about the HIFs being self adapting. I seem to 
remember the manual mentioning a 1/32" gap between the choke spindle and 
the throttle stop arm on the throttle spindle and I tend to leave that 
much play with any carb to be sure the throttle plates are seating where 
they should be.

Also, you didn't mention whether you adjusted the valves lately. That 
can also change with heat. Should be .015 cold, .013 hot. These engines 
will take a fairly large amount of leeway, but you do need to be sure 
they're all at least closing and opening near where they should be.

You did put a heatshield in there didn't you?

Last, I'd set your idle at 850 - 900 minimum. When the factory said 750 
they were using very different fuel.

My two cents.

Glenn

On 7/8/2012 1:00 PM, mgs-request at autox.team.net wrote:
> Date: Sat, 7 Jul 2012 13:19:05 -0700
> From: Aaron Whiteman<awhitema at panix.com>
> To: MG List<mgs at autox.team.net>
> Subject: [Mgs] hot idle troubles
> Message-ID:<75F1992C-52A8-453A-88E7-B8A2BAC377BD at panix.com>
> Content-Type: text/plain; charset=us-ascii
>
> Now that the Winter that Would Not End has ended and Eastern Washington is
> seeing close to normal temps, I'm seeing some trouble with my car's idle.
>
> '75 MGB, retrofitted with SU HIF4 from a '73; carbs recently serviced by
> Brooklands British of Tacoma to fix a vacuum leak in the throttle bushings.
>
> Start up car, drive for 8 miles.  Every thing is good, traffic lights
> irritating to driver, but car runs normally.
> Stop to pick up some stuff.  Rest for a few minutes.
> Get back in car, drive to end of block, reach stop sign, car dies.
> .. car dies at all stops for the next few miles unless I give extra throttle.
> Drive 8 miles back home, all is good again.
> Stop for coffee.
> Get back in car, car dies at intersections once again.