Airworthiness Directive: 129
Date: June 9, 2003
Subject: Engine Torsion Strut Bolt & Coolant Socket Tube Interference 
Compliance: Mandatory
Models Effected: S-12, S-12XL, S-12S, S-14 with ROTAX 912/912S
(assembled or under construction)

Due to variations in water pump Bent Socket installation and vibration tendencies of some engines, 
aircraft have experienced minor to severe impacting of the Engine Torsion Strut Bolt on the Lower 
Right-Hand Water Pump Bent Socket Tube. This impaction has caused some hose clamps and 
socket tubes to be damaged or compromised. Loss of coolant may result. Also, rubbing of hose 
clamps on engine mounts or bolts may transmit unwanted vibration into airframe. 


Before next flight or during assembly of unfinished airplanes:

1. On flying aircraft: Visually inspect for any rubbing of the bolt head on the water outlet socket, 
hose or hose clamp. Replace "S"-Shaped Hose (RANS part # KSPW0025), Bent Socket 
(ROTAX part # 922-232) and Hose Clamp (ROTAX part # 251875) as needed.

2. All Aircraft: Install two (2) extra 1/8" Aluminum washer (RANS part # EG-AW) under each 
Barry Mount. This will space the engine 1/4" higher for additional clearance. Six (6) AN6-25A bolts 
will be required. See FIGURE 1-129 below for details. Check all hose clamps for engine mount clearance. 
Periodically check during operation for clearance.



The "S"-Shaped Hose and Aluminum Washers are available through our parts department. 

Order as required: 

1	KSPW0025	"S"-Shaped Hose"	$16.50
12	EG-AW	1/8" Aluminum Washers	$2.00 each
6	AN6-25A	3/8" Bolts	$2.88 each

Prices do not include shipping

ROTAX parts are available from Authorized ROTAX dealers.

Thank you for your attention to this matter. Hopefully we have not inconvenienced you to any great degree.

Fly safe.