IO-390-D Series Engine Maintenance Manual
© 2020 Avco Corporation. All Rights Reserved
73-10
March 2020
Page 263
IO-390-D Series Engine Maintenance Manual
(5)
Torque each fuel line fitting in accordance with the Standard Torque Tables in the latest
revision of the
Service Table of Limits - SSP-1776
.
Figure 6
Fuel Injector Lines
(6)
Make sure that the fuel lines are securely held in place, attached to the engine (to dampen
vibration during flight) with the necessary serviceable cushioned clamps and hardware.
Install clamps on the fuel line as per the following guidelines:
(a)
Make sure each serviceable clamp securely supports the fuel line to prevent fuel line
movement due to vibration, friction, or motion frequencies during flight.
Do NOT
use plastic tie straps as clamps.
(b)
Install serviceable clamps (preferably with cushions) on the fuel line. Make sure the
cushion is not missing and is intact, and completely covers the fuel line diameter. If
cushions are deteriorated or missing, replace the clamp with a new clamp with the
cushion intact.
(c)
Refer to Figures 4 and 5 which show how the fasteners are to be installed on P-clamps
and L-shaped clamps.
(d)
Make sure the clamps are securely attached to support the fuel line and to prevent
movement from vibration or motion frequencies.
(e)
On engines that used metal clamps with no cushion, use the P/N LW-12598 fuel line
sleeve at each of those clamping locations. (Do not use the fuel line sleeve with the
serviceable cushioned clamps.)
(f)
Torque the fuel line union nut (Figure 7) between 35 to 50 in.-lb. (4 to 6 Nm).
