Injection Measurement Vial & Carburetor Maintenance

If you have 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?

All mechanical parts, including carburetors,  need maintenance.  Eventually you
will have drive 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.  And at some point you will find some weeping where
gaskets are starting to get old and losing their seal.  Then you need to get a
rebuild kit and replace those parts. The original shop manuals, and many after-
market manuals, offer more 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, refer to our
troubleshooting page for detailed information.



                    Carburetor maintenance requires a few specific tools:
                                 The short stubby slotted screwdriver for adjusting jets
                          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 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.  We set the float levels on our restored
carbs, and its unlikely that you will have to do much here anyway.  And if you do,
there is a view port so the float can be set by sight.

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.
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
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