MDE-4334C Atlas Start-up and Service Manual · April 2008
Page 7-75
Mechanical Computers
Hydraulic/Mechanical Components
Troubleshooting
Read and follow all safety precautions as outlined in
The following table lists possible problems and their causes.
Problem
Possible Causes
Meter runs on without leaking
• A leaking inner hose O-Ring
• Inner hose leak
• Leaking hose Venturi or Co-Vent check valve
Venturi or Co-Vent does not drain hose
• Leaking hose or O-Ring
• Leaking Venturi or Co-Vent check valve
• Improperly positioned Venturi or Co-Vent pick-up (must be near the
normal low drape of the hose)
• Hose installed upside-down
Nozzle clicks-off prematurely
• Trap in underground plumbing
• Trap at dispenser plumbing (do not use rubber hose)
• Restricted vent at tank
• Bad nozzle
• Topping off of tanks by customer
• Defective Venturi or Co-Vent
Mechanical Computers
Although the mechanical computers used in Gasboy pumps are carefully adjusted and
lubricated at the factory before shipment, they require (as do all mechanical parts) occasional
cleaning and lubrication when in service. The intervals at which this should be done vary with
conditions of operation. Under normal conditions, service of computers is required only twice
a year, or after each 100,000 gallons (378,000 liters) delivered.
Shut off and lock out the AC power to the pump. It is easier to clean and oil the mechanical
computer if you remove it from the pump. Clean the mechanical computer with compressed
air and wipe all accessible parts (such as figure wheel drums) with a clean cloth.
Note: Always wear protective safety goggles or glasses while using compressed air.
Never use solvents, such as gasoline or kerosene, as this will be trapped in many of the
inaccessible bearings and dissolve the new lubricant when it is applied.
A light, non-acid type oil (SAE 10) is recommended as it gives maximum protection in
varying temperatures. The oil must also be acid-free so that it will not cause corrosion of the
cast metal parts. A long handled, fine lettering brush is very convenient for applying the oil to
all bearings and shafts and for applying light, non-fluid oil (grease with body similar to that of
chassis lubricant) to bevel-type gears.