spitfires
[Top] [All Lists]

Re: Stromberg carb problem, Chapter 2

To: trunnell@mindspring.com (Glenn Trunnell), spitfires@autox.team.net
Subject: Re: Stromberg carb problem, Chapter 2
From: Atwell Haines <carbuff@nac.net>
Date: Fri, 02 Apr 1999 07:10:34 -0500
Glenn,

Have you looked for vacuum leaks

A) caused by loose vacuum line 'elbows' 
                     or 
B) the o-ring inside the needle adjusting screw?

These two things made MAJOR mixture differences on my car.

Have you tried both the Grose-Jet and the regular needle & seat on the
floats? Is the float pivot pin in good shape? What is the manifold vaccuum
at idle?

Atwell Haines
'79 Spitfire

At 10:31 PM 4/1/99 -0500, Glenn Trunnell wrote:
>
>Hi,
>
>Just wanted to update  everyone on my crusade to make my Stromberg carb.,
>perform the way I imagine it did when my car left the factory.  So far I
>have rebuilt the carb myself, and then had it rebuilt by apple hydraulics
>in NY.  It has new throttle bushings etc. but still will only idle well
>when it's adjusted all the way rich.  I took the car to my local LBC shop
>and they tinkered with it for about a day and then switched it with another
>carb which seemed to run much better, they let me take the car for the
>weekend to try out and see if I felt that it was running properly.  They
>encouraged me to tinker with it, so I pulled off the top to examine the
>needle and spring.  This is an early carb and has the B5CH needle installed
>and what appears to be the same spring as my original carb.  this carb is
>also adjusted competely rich so no progress there.  The B5CH needle was
>very worn, but looked much smaller than my B1DL needle that's in the
>original carb.  Does anyone have the dimensions of these two needles?  I
>have the Haynes weber/su/stromberg book and it lists the needle, but the
>specs aren't there.  It seems that several pages are missing in that
>section, does anyone else have the same problem with this book?  I have had
>a head job done on this engine, but I'm beginning to believe that the
>problem may be worn valve guides allowing a little extra air into the
>cylinder when the intake opens, the car doesn't burn any oil, but Spitfire
>heads are so under lubricated, there's not much oil up there to seep
>through the guide and burn.  Does anybody have any experience with this
>problem?  I'm going to try the carb cleaner test on the valve stems and see
>if I can isolate the problem this weekend,  I'll keep ya'll posted on my
>results.
>
>Glenn Trunnell
>'79 Spitfire (I wish I had the Dual SUs)
>
>
>

<Prev in Thread] Current Thread [Next in Thread>