|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
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
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.