1.    Moth Modification 155: to provide a positive locking of the fuel cock in the ON position is in two Parts. Part 1 is applicable to DH 82A aircraft and Queen Bee and Part 2 is applicable to DH 82 aircraft.

2. List of Parts.

DH82A and Queen Bee.

Part	Part No.	Material	Size	Qty
Plate	H43262	L164	16 swg	A/R
Angle	H43263	L164	16 swg	A/R
Tab	H43264	L164	16 swg	A/R
Rivet	SP 80	L86	3/32 in	10
Spring	H43265	S513	27 swg	A/R

NOTE: An alternative to S513 material for the spring may be used with the approval of local Airworthiness Authority.

DH82

Part	Part No	Material	Size	Qty
Plate	H43266	S513	21 swg	A/R

3. To embody Moth Modification 155 proceed as follows:

A. Part 1. Moth DH 82A and Queen Bee aircraft only.

(1) Locate the fuel ON/OFF cock in the rear cockpit, port side (Fig l).
(2) Remove the fuel system indicator plate, Part No H36086A.  Retain fixing screws (2 off).
(3) De-rivet the fuel ON/OFF label, Part No H35797 from the indicator plate. Retain fuel ON/OFF label and discard indicator plate.
(4) Manufacture new indicator plate Part No H43262, angle Part No 43263, tab Part No H43264 and spring H43265 to dimensions given in Fig 2.
(5) Assemble parts manufactured in Step 4 and label retained in Step 3 to make new fuel system indicator plate assembly H43261A.
(6) Fit modified fuel indicator plate assembly to the rear cockpit, port side, and secure with the fixing screws retained in Step 2.
(7) Select fuel ON/OFF cock to the On position and ensure that the control is positively held in the ON position by the spring (Fig 3).
(8) Select fuel ON/OFF cock to OFF.

B. Part 2, Moth DH 82 aircraft only.

(1) Locate the fuel ON/OFF cock in the rear cockpit, port side (Fig 4).
(2) Remove the 2 bolts, units and washers from the support bracket H35793 which secure the fuel indicator plate H35798 in position on the square tube.  Retain bolts, nuts and washers.
(3) Manufacture locking plate Part No H43266 to the dimensions given in Fig 5.
(4) Assemble the locking plate, Part No H43266 and the fuel indicator plate Part No H35798 to the square tube with the support bracket H35793.  Secure with the bolts, nuts and washers retained in Step 2.
(5) Select fuel ON/OFF cock to the On position and ensure that the fuel control rod is positively held in the ON position by the tang on the locking plate (Fig 6).
(6) Select fuel ON/OFF cock to OFF.

Drawings:
Figure 1: DH82A and Queen Bee - Fuel ON/OFF cock (pre-Mod 155)
Figure 2: DH82A and Queen Bee - Manufacture, assembly and installation of Mod 155
Figure 3: DH82A and Queen Bee - Fuel ON/OFF cock (post Mod 155)
Figure 4: DH82 - Fuel ON/OFF cock (pre-Mod 155)
Figure 5: DH82 - Manufacture, assembly and installation of Mod 155
Figure 6: DH82 - Fuel ON/OFF cock (post Mod 155)

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