WACO YMF F5 Series Maintenance Manual Download

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WACO Classic Aircraft Corporation

YMF WACO F5 SERIES MAINTENANCE MANUAL

REVISION: H

Page

RELEASED: 07/21/2017

PART NO. YMFAMM-1

SECTION 8

SYSTEMS

8.1

GASOLINE SYSTEM

Your WACO airplane is equipped with what is considered the simplest, most practical gasoline system
obtainable, namely, a direct gravity flow of gasoline from wing tanks to carburetor. However, owing to the
comparatively thin wing section, it is necessary that these tanks be fairly long and shallow.

These tanks will drain to almost the last cup of gasoline in a normal flight position, but it is important that
you have at least ten gallons of gasoline in the tank USED for take-off before a take-off is attempted. We
recommend that a take-off never be made without at least ten gallons of gasoline in the selected tanks.
This will insure a steady and continual flow of gasoline to the carburetor.

Another item to take into consideration is that on the ground the gasoline will collect at the lower end of
the tank. Since the gauges are located pretty well in the center of the tank, an accurate reading cannot
be obtained from the gasoline gauge on the ground,

although, these gauges are quite accurate for use in level flight. Therefore, particular care should be
taken in checking the gasoline supply while the ship is on the ground.

It is important that the vent lines protruding from top tanks be kept open at all times. It is also important
that gas tank caps fit snugly and do not leak. Occasionally, the steel clip fittings which hold these tank
caps in place will get pulled out of shape and not have the correct tension. This can be quickly remedied
by putting them back in shape with a pair of pliers and if this fails to stop the leak, the cap should be
replaced.

You need not be alarmed if after filling the tanks completely, one tank appears to drain faster than the
other does. This is normal and there is no set rule as to which tank will drain fastest under certain
conditions. On some airplanes one tank will drain faster one day and the other the next day.

You will note the tanks have been provided with two outlet lines, one at the front and one at the rear. This
is to take care of all conditions and make sure the carburetor gets gas both during a steep climb and a
steep descent.

If the tank appears to leak, first make sure that all fittings are tight before going tot he trouble of removing
the tanks. Leaks are usually found to be around the gasoline gauges or one of the fittings and easily
repaired by tightening, or, if necessary, removing and adding filler such as thread dope or white lead to
the threads and replacing.

Gas Tank Vent Fittings

Screw vent lines in place in upper surface of upper wings taking care to have openings in gooseneck line
towards the REAR.

8.2

OIL SYSTEM

The engine oil system consists of a five gallon reservoir mounted aft of the engine on the top of the
engine mount and is connected to the engine pressure pump inlet and scavenge pump outlet with ¾ inch
aluminum and Mil 6000 rubber lines. There is a removable brass screen housing mounted on the firewall
through which all oil passes prior to entering the pressure pump inlet. This screen can be removed for
cleaning at each oil change (see inspection schedule). There is an oil cooler mounted on the left side of
the engine mount through which all return oil from the engine scavenge pump passes prior to entering the
oil reservoir. See the Jacobs Operators Manual in Section 10 of this manual for additional information.

8.3

ELECTRICAL SYSTEM

The electrical system consists of two 12 volt 25 or 35 AH lead acid batteries housed in a sealed battery
box mounted aft of the engine compartment ahead of the firewall and connected in series to provide 24
VDC to the main A/C buss and is identical for both the A2 and the B2 engine installations. The battery
charge is maintained by the gear driven JASCO 50 Amp alternator mounted on the engine accessory
case and controlled by a JASCO solid state Regulator/OV-protection module mounted on the firewall. All
circuits are protected by circuit breakers. There is a 24 volt E80 starter mounted on the accessory case at
the rear of the engine. See Section 10 for wiring diagrams.