Carburetor maintenance and Injection measurement vial

If you have recently purchased a set of restored/remanufactured carburetors,
injection and float levels are set. The throats have been synchronized for air
flow.  So why do you need to do maintenance?  If you have an older set of
carburetors, have you been keeping up with your routine maintenance,
also called a "rebuild"?

All mechanical parts, including carburetors,  need maintenance.  Eventually you
will have driven 10,000, 25,000, or more miles.  Even if you don't put a lot of
miles on your engine every year, shafts, springs, etc should be checked for
wear, lubrication of moving parts. If you leave gasoline sitting in your carbs for
long periods of time, the gunk it leaves behind as it evaporates will clog jets,
cause your floats to stick, gum up moving parts, and seal off the smaller
passageways in the carbs.  It will also degrade seals and gaskets.  on the other
hand, carbs run dry and left for long periods of time will see the gaskets and
seals dry out and crack.  Leaking seals can mean gasoline leaking into your
engine.  leaking gasoline eventually resolves itself - as FIRE!
Periodically,  get a rebuild kit and replace those parts. The original shop
manuals, and many after- market manuals, offer  details on carburetor
maintenance. You can also refer to our manual  pages if you don't have your
own.
Zenith                                                     Solex

If you are wondering about your carburetor's performance, give us a call



             Carburetor maintenance requires a few specific tools:
                          The short stubby slotted screwdriver for adjusting jets, various  
screws, even making it easier to move some of
the volume control screws.
                   The Unisyn or (preferably) the Synchrometer
The float guage
                    An injection measurement vial


The screwdriver is an easy item to obtain, whether you prefer the one from the
original tool kit, or what ever you picked up at the hardware store

The Unisyn is a bit more difficult to use and find, which is why the Synchrometer
is peferred, being easier to use and most definately easier to obtain.  Usually,
the base has to be adjusted for a tight fit in your particular  carburetor; some
electrical or duct tape works well for this.  Your restored carbs have already
been synchronized, but it is something you will want  to monitor over time,
especially  after rebuilds, etc.

The float guage has become an NLA item for Zenith.  Sometimes you can find a
P78 guage, the tool for Solex.  We set the float levels on our restored carbs, and
its unlikely that you will have to do much here until you get to your rebuild.   
Instructions for setting
the floats manually can be found on this web site
Zenith              Solex

Injection measurement vials were originally glass, and came with a little bit of
wire that allowed the vial to be dipped under the injector in the carb,   These
glass vials are difficult to find.  We were fortunate enough to find some plastic
vials in the correct size.  Add a bit of wire and measure your injection.

These vials are too big for use with Normal Zenith (PO3) carburetors, but can be
used with Super (PO2) and C (PO19) Zeniths, as well as all the Solex carbs.
Injection vial
Float guage
How to use the vials:

After attaching the wire, hold the vial under the injector
and press the throttle lever twice, then read how much
fuel is in the vial. If you are using the factory manual's
guidelines, note that we have found the lower end of
the original factory specs gives the best results with
today's modern fuels.  Those are the numbers noted here.

For Super and C Zeniths, 0.25ml
                 shorten the pump link to increase the fuel
                 lengthen the pump link to decrease the fuel

Solex 40PII-4, solid or split shaft, 0.35ml
                     all Solex are adjusted the same way, by adjusting the two nuts on
the end of the pump rod - moving them in to increase injection, moving them out
to decrease injection

Solex 32PBIC/PBJ and 40PBIC/PICB,  0.5ml


Remember to call us if you have any questions!!
928-204-0507