Date: 201709
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Aircraft: Citation X (C750)
Aircraft component: Nosewheel Steering
Component problem: Malfunctioning; Improperly Operated
Reporter function: Technician
Reporter qualification: Maintenance Inspection Authority
Human factors: Troubleshooting
Second reporter function: Technician
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Maintenance
When detected: Routine Inspection
Result: General Maintenance Action
Contributing factors: Manuals; Procedure; Aircraft
Primary problem: Manuals

Narrative: [We] worked a repeat squawk on this aircraft for a nose wheel shimmy. We determined that the upper and lower nose gear torque links needed changed. My colleague was doing the maintenance and I was inspecting his work. On the previous write up for this squawk; another vendor had replaced all hardware for the torque links. I requested the upper and lower torque links and bushings from MCC (Maintenance Control Center) per CE750 CMM (Component Maintenance Manual) 32-20-02-XXXX. I originally requested items number 97 and number 315 for the upper and lower torque links. I later talked to MCC and they told me that they had ordered the torque links with the bushings already installed so they didn't order bushings.When we received the parts for the aircraft; I checked the paperwork for the torque links and noticed that the part numbers for the torque links didn't match the item numbers I had originally requested. I then looked in the CMM to verify that these were the proper parts. They were the complete assemblies including bushings per the CMM (items number75 and number 300). There is no verbiage in the CMM that explains what the complete torque link assemblies contain.We removed the upper torque link from the aircraft and carefully set aside all hardware from the assemblies. We did the upper torque link first and reinstalled the new torque link with the hardware removed from the old assembly. We torqued all hardware per the maintenance manual and safe tied the nuts. We then did the same for the lower torque link. Both upper and lower torque links were free of play at this point when you attempted to move them by hand.We were later informed that there were spacers (item number 83) that were not installed with the assemblies. These spacers were not installed on the assemblies prior to us removing them for replacement. A video from the vendor who found this shows that there is a lot of play in the torque links. In the video however; the condition of the torque links is not as the vendor found them. He had obviously removed the cotter keys from the nuts and loosened the torque as there are no threads visible past the nuts. We had the nuts torqued and safe tied when we changed the torque links. The excessive play shown in the video was not present after we torqued the nuts.I believe that the component manual should contain a detailed description of what parts are included in the complete torque link assemblies. It's very easy to overlook the spacers on installation because the drawings could lead you to believe they could have been part of the torque link assemblies.


Second narrative: [We] worked this aircraft. It was a repeat write up for nose wheel shimmy we determined that the upper and lower torque links needed replaced. The parts were placed on order MCC (Maintenance Control Center) changed the order to a different part number that already had the bushings installed. All of the other hardware was replaced by another vendor on a previous squawk. We removed the hardware and replaced the torque links; reinstalled the new torque links using the original hardware and torqued per the 750-maintenance manual. [We then] installed new cotter pins; checked the torque links and there was no play. The spacers that are missing were not installed when we replaced the torque links. The video sent in of the play was taken with all the hardware loose.


Synopsis: Two Maintenance Technicians working on Citation X (C750) reported that items for the nose gear torque links were missing from a previous repair.