SA1396SO
Remove drain plug, Cessna Part Number AN814-3DL, from the fuel selector valve, and replace with CAV-180 (MT-1072-77) or CAV-180H-4 (CM-172-77) (*Model: C-172N Serial Nos.: 17261445, 17267585 through 17269309 (1977 Model), 17261578, 17269310 through 17271034 (1978 Model), \t(Except 17270050), 17271035 through 17272884 (1979 Model), 17270050, 17272885 through 17274009 (1980 Model)). Held by Saf-Air Products INC., which holds 10 approved modifications in all. Last revised September 28, 2020. System: engine.
What it applies to
- Kind of product
- Aircraft
- Design holder
- The Cessna Aircraft Company
- Models
- 172N
- Type certificate
- 3A12
- On this site
- Cessna 172 Skyhawk 20,669 registered
- The FAA's record
- On the FAA's site
What an approved modification is
A supplemental type certificate is the FAA's approval of a change to a certified design: a new engine or propeller, avionics, an autopilot, floats, a parachute, a larger fuel tank, an ice-protection kit. The company holding it may sell the kit and the paperwork to owners of the listed models; the modification then becomes part of that aircraft's record. The FAA's list says what was approved and for which models, not how many aircraft carry it.
Source: FAA supplemental type certificates (Dynamic Regulatory System). Register counts from the FAA register of October 12, 2026.