Cub Cadet Challenger 500, Service Manual

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Engine Management System
7 ‐ 3
Software/Calibration Re-flashing procedure. In the event of ECU hardware failure or
malfunction (during warranty period only) the ECU should be sent back to the vehicle
manufacturer giving complete details of the ECU part number, serial number, vehicle
model & make, manufacturing date, total miles run on the vehicle, location of use,
vehicle number and date of return.
2) Multec 3.5 Fuel Injectors

The Multec 3.5 Fuel Injector is an electromechanical device. A magnetic field is
generated as voltage is applied to the solenoid coil. The resulting magnetic force
lifts the core assembly, overcoming manifold vacuum, spring force, and fuel
pressure, allowing fuel to pass through the ball and seat interface to the director.
As the fuel passes through the director, an atomized spray is developed. The
injector closes when the voltage is removed, cutting off the fuel flow.

This is a critical part to the fuel delivery on the UV, therefore, there are things
you should not do when working with a fuel injector.
Do not reuse injector seal
rings, dip injector tips into lubricants, cycle injectors repeatedly without fuel
pressure, pulse a high leak rate injector, allow water into the fuel system,
contact or apply load to the injector tip, use a dropped unit, pound on injectors
during assembly into the manifold, store injectors or assemblies in an
unprotected environment.

Things to Do when handling fuel injectors. Use the proper lubricant on the seal
ring when installing, pulse actuate a stuck closed injector (5 sec at 9 – 15V),
pulse activate prior to a dry fuel system leak test to seat the injectors, Return any
dropped or damaged injector with a tag describing the problem (warranty cases
only).
3) Installation guidelines
Follow these guidelines to prevent damage to the injector and its electrical
interface during the replacement or installation process.

Lubrication: Apply a light coating of lubricant to the lower injector seal ring. ISO
10 light mineral oil or equivalent is recommended.

The preferred technique is to apply the lubricant to the sockets the injectors are
being installed into, rather than directly to the seal ring itself. This will help
minimize the possibility of injector contamination.