I'm finding myself somewhat befuddled in adjusting a Single Stromburg
Carb. Silly me, I thought to myself, how hard can it be? I've adjusted
and rebuilt many a carb before. But nooo! This carb wants to play
strange games. It isn't helping matters that nothing I've come accross,
even the Stromburg Carb Tuning Manual, mentions an order to adjust things
in. Grr!
So, here I am with a running Spitfire that wants to idle at around 1500
rpm. I have determined that my vacuum retard on the distributor has a
hole in it. But when it comes to adjusting the carb itself, I'm a bit in
the dark.
Idle speed screw backed all the way out and not touching, no difference
in idle speed.
Idle mixture screw (both coarse and fine) I can make it run ragged, but
that's it, which is allright).
Main piston, results vary all over the place with regards to slightly
lifting the piston and noting engine rpm change. I've made no needle
adjustments yet since I put it all back together.
That air bleed screw thingie on the side, screw it out and eventually the
engine just starts dying on its own. It will not simply lower rpm, it
just keeps on going down until the engine stalls. If I adjust it till
the engine barely keeps that 1500rpm idle without always dying, it's very
ragged on acceleration and high(er) rpms.
Choke, I have one, it worked the first time I started the car. Haven't
noticed it doing anything since then. But then, I've lost track of how
this thing works down inside that carb (where's the front butterfly?!).
If it's an enrichner circuit, I don't know where it draws air from.
Noise is entertaining, hell of a rushing sound at idle. Just off of this
high idle, and the sound completely disapears.
Any sage comments would be welcome at this point as it regards to this
most interesting of carbs. And to think, I really thought years of
experience with cv and vv motorcycle carbs would help me here! <g>
Especially telling me where to start and what order to go in.
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