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Re: Fw: Two SU means twice the problems

To: James Carpenter <james.carpenter@jccsystems.swinternet.co.uk>
Subject: Re: Fw: Two SU means twice the problems
From: Joe Curry <spitlist@gte.net>
Date: Fri, 02 Apr 1999 11:42:34 -0800
James,
The worn shafts probably don't help the situation, but is seems to me
that if you experience acceleration when you lift off the accelerator,
it would mean that the mixture is too rich and easing up tends to
correct the situation resulting in increase of power at that time.

While using silver solder to build up the shaft diameter may effect a
solution to that problem, I'd guess that it would only be temporary. 
You really ought to have the channels align bored and standard size
bushings installed along with new shafts.  The shafts are not all that
expensive and the fix will be more of a long term one than using silver
solder.

After doing the shafts, re-tune the carbs according to the Haynes manual
and I'd bet you will see amazingly improved results.

Regards,
Joe Curry

James Carpenter wrote:

>Just fitted my new stock exhaust back box to replace my Swiss cheese old
>exhaust.  Just so you know UK 1500 duel SU's supposed to have 71BHP and do
>101mph.
>
>It's now going as fast as it has in ages, 68mph, although my old shot
> carbs would get 81mph.
>
>The car now revs to 5200 rpm under load :-)
>
>Unfortunately the fixed exhaust has brought to the front my carburation
>problem.
>
>It's completely bizzar!
>
>At high speeds (55mph+) easing off then accelerating has bizzar effects.
>After you have eased off when you accelerate you expect some kick but you
>dont get any, after that sometimes easing off will cause you to
> accelerate.
>It defies logic. You maybe get a smell of petrol.
>
>How much of a problem is warn throttle spindles for full power high revs
>(2500 and over)?
>
>Could this be something to do with the fuel pump.
>
>Or my warn engine upper half.
>
>The next mail
>
>An update here,
>
>I have just stripped the right carb and melted onto it some silver solder
>where the spindle was warn.  I then used some wet and dry to bring the
>profile back to ordinary.  I am quite pleased with the results, the
> profile
>is now very smooth, and I have lost 3/4 the play in the spindle.  I will
>put
>this carb back then strip and tin the left carb later tonight.

-- 
"If you can't excel with talent, triumph with effort."
 -- Dave Weinbaum in National Enquirer

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