6-4 Standard Practice Maintenance Manual
15 April 2016
Engine Inspection and Service
GTSIO-520-F, K
1
1200/12
GTSIO-520-C, D, H
1, 4
1600/12
GTSIO-520-L, M, N
1
TSIO-520-B, D, E, J, K, L, N
1
1400/12
TSIO-520-BB, C, DB, EB, G, H, JB, KB, LB, M, P, R, T
1, 2
1400/12 1600/12
TSIO-520-NB
1, 2,
1600/12 1800/12
TSIO-520-M, P, R
1, 2, 5
TSIO-520-AF, CE, UB, VB, WB
1, 2
L/TSIO-520-AE
1, 2
2000/12 2200/12
TSIO-520-BE
1, 2
IO-550-A, B, C, D, E, F, L
1, 2
1700/12 1900/12
IO-550-G, N, P, R
1, 2
2000/12 2200/12
IOF-550-N
1, 2
TSIO-550-B, E
1, 2
1600/12 1800/12
TSIO-550-C, G, K, N
1, 2
2000/12 2200/12
TSIOF-550-D, J, K, P
1, 2
TSIOL-550-A, B, C
1
2000/12
1. If an engine consistently accumulates 40 or more hours per month since being placed in service, add 200 hours to recom-
mended TBO.
2. Engines with Serial Number 1006000 or higher include an additional 200 hours to TBO (as noted in Table 1, column 3).
3. Applies to: new and rebuilt O-470U Model Specifications 11, 12, 13, 14, 17, 18, and subsequent numbers manufactured, new
or rebuilt, or overhauled (2002 or later).
4. Applies to GTSIO-520-C, D, H engine models listed utilizing cylinder part number 653453, or superseding (cylinder produc-
tion released APRIL 1993-verify part number on cylinder flange). Also, all parts must be replaced as directed by the applica-
ble current service bulletins, illustrated parts catalogs, and overhaul manuals. A log book entry is required.
5. Applies to new and rebuilt TSIO-520-M Spec. 6, 7, and 8; TSIO-520-P Spec. 5 and 6; TSIO-520-R Spec. 7, 9, 10, and 11, or
new and rebuilt TSIO-520-M, P, and R model engines with subsequent specification numbers.
Table 6-1. Engine Time Between Overhaul (TBO)
ENGINE MODEL SEE NOTE
HOURS/YEARS
ENGINE
S/N BEFORE
1006000
ENGINE
S/N 1006000
AND LATER