Probably the needle has become unscrewed from its adjustment screw on the
piston,
and fallen to a excessively low position. You need to take out the piston and
screw
the adjustment in the bottom of the oil chamber until the needle starts moving
upwards.
Then make sure that the retaining star washer that surrounds the adjustment
screw has not become forced upwards. If so, it needs to be pressed back down.
Finally, make sure you know the adjustment range of the needle, and make
sure you don't ever adjust it too far downwards (lean), or it will get
unscrewed again.
Probably after that, you can reset all the other adjustments to a normal range.
This problem had me stumped for a couple of years back when I first
got my car. A very experienced mechanic (Charles Rockwell of Santa Clara, CA)
spotted the froblem and fixed it in about two minutes...
Doug Braun
'72 Spit
At 09:02 AM 4/12/2003 -0400, Greg Schluge wrote:
>As it turns out I have only figured out part of the carburetor problems. I
>fixed the fuel pouring out of the throat problem. I do have an update on
>that. Just polishing the float lever is not good enough. I filed the lever
>depression out and re-buffed it to a mirror finish. I also noticed that the
>new needle valve had a sharp stub on the top of the needle where it slides
>against the float lever. Probably a manufacturing remnant. Needless to say,
>that is now buffed out and the float exactly on 17 mm.
>
>The new problem is that I can get a good idle, but lean running after that. I
>have the bypass valve at it's most insensitive position and the fine idle
>screw is two turns out. With that said, I can pretty much do anything with
>the main jet needle adjustment and nothing changes.
>
>I am thinking that it is a main jet problem. I pressed the main jet out of a
>parts carburetor and it was not hard to do at all. Does anyone know if the
>main jet is available from any source?
>
>Any other suggestions? The timing is 10 degrees, Valve adjustment done, and
>the car runs perfectly with an old 71 carb from the car I am rebuilding.
/// spitfires@autox.team.net mailing list
/// or try http://www.team.net/cgi-bin/majorcool
/// Archives at http://www.team.net/archive
|