SUBJECT: CRANKSHAFT INSPECTION

PURPOSE: Provide Instructions for the Inspection of the Number Two and Five Crankshaft Cheeks.

COMPLIANCE: Within the next 10 hours of operation for the affected engines and crarikshafts listed below, provided the engine has a minimum of 35 hours and less than 300 hours of operation. Crankshafts with less than. 35 hours of operation should be inspected when the total hours of operation have reached 35 hours but before accumulating 50 hours. Affected engines with more than 300 hours of operation do not require inspection.

ENGINES AFFECTED: IO­520, TSIO­520, LTSIO­520, IO­550, TSIO­550 and TSIOL­550 series new and rebuilt direct drive engines manufactured between March 1998 and July 1998 with serial numbers specified below or any of the preceding series engines that have had affected crankshafts installed:

AFFECTED ENGINES BY SERIAL NUMBER:

AFFECTED CRANKSHAFTS:

Crankshaft Part Numbers 646623, 649134, 649898, 649900 or 652359 purchased between March 1998 and July 1998 that have serial numbers beginning with the following letters and first four digits: C1098***, C1198***, C1298***, E0898***, E1198***, E1298***, E1398***, E1498***, F0998***, F1098***, F1198***, F1698***, F1798***, F1898***, F1998***.

Example: Crankshaft P/N 646623 S/N C109812N

Uninstalled crankshafts must be returned to TCM for replacement. Contact your TCM Distributor for instructions.

GENERAL INFORMATION:

INSPECTION OF NEW AND REBUILT AFFECTED ENGINES AND ENGINES THAT HAVE BEEN OVERHAULED OR REPAIRED UTILIZING THE SPECIFIED NEW CRANKSHAFTS.

Teledyne Continental Motors has become aware of a small number of new, low time crankshafts that have fractured. The reason for the fracture is under investigation. Inspection of affected engines and any engine in which an affected crankshaft has been installed is required.

THE INSPECTION REQUIRED BY THIS SPECIAL SERVICE INSTRUCTION IS INTENDED TO DETECT CONDITIONS WHICH IF LEFT UNCORRECTED WILL RESULT IN ENGINE FAILURE.

PRE­INSPECTION:

1. To perform the required inspection, remove the engine cowling in accordance with the aircraft manufacturer's maintenance manual to gain access to the engine.

2. Remove engine baffling and engine mounted equipment as required to facilitate removal of cylinders number 1 and 3.

3. Remove cylinders number 1 and 3 in accordance with the applicable engine maintenance manual, overhaul manual or aircraft manufacturer's maintenance manual. Remove the cylinder only far enough to expose the piston pin. Push the piston pin out of the connecting rod bushing only far enough to release the piston and piston pin from the connecting rod, leaving the piston in the cylinder.

The number one and three connecting rods will have to be removed to perform the dye check inspection.

ANYTHING DROPPED IN THE ENGINE MUST BE REMOVED.

4.. Position the connecting rod to be removed (number one or number three) at or near top center. See Figure 1.

Note: The 520 and 550 series engines may have connecting rod nuts secured with cotter pins or they may have spiral­lock nuts. Spiral­lock nuts are free spinning self­locking fasteners. When removing Spiralock nuts you may find it necessary to tighten the nut slightly to release the self­locking feature.

5. Remove, if utilized, the connecting rod nut cotter pins and discard them. Remove the connecting rod nuts.

6. Carefully separate the connecting rod from the connecting rod cap. Support the connecting rod cap while removing the connecting rod from the crankshaft. Repeat this procedure for the other connecting rod.

DETAILED INSPECTION:

A. VISUAL INSPECTION:

1. Using a soft shop towel, dampened with solvent, remove any surface residue from the aft side of the number two and five crankshaft cheeks. The outboard area at the edge of crankshaft cheek next to the counterweight is the area to be inspected. See Figure 2 and 3.

2. Using a flashlight and mirror inspect the aft side of the number two and five crankshaft cheek for indications of a crack. The inspection area is between the counterweight blade bushing holes at the edge break from the crankshaft cheek to the blade web. See Figure 2 and Figure 3.

3. If a crack or crack indication is noted telephone Teledyne Continental Motors at 334­438­3411, ext. 8354.

4. If the visual inspection does not reveal any cracks perform a dye check of the aft side of number two and five crankshaft cheek as follows.

B. DYE CHECK INSPECTION:

The dye check inspection will be performed using Magnaflux Spot Check or equivalent.

To inspect the number two crankshaft cheek aft face, place the number one connecting rod journal at a position just before bottom dead center. See Figure 3.

To inspect the number five crankshaft cheek aft face, place the number three connecting rod journal at a position just before bottom dead center. See Figure 4.

1. Using a soft shop towel, dampened with acetone solvent, remove any surface residue from the aft side of the number two and five crankshaft cheeks. The outboard area at the edge of crankshaft cheek next to the counterweight is the area to be inspected. See Figure 2, and 3.

2. Using spot­check remover, thoroughly clean the aft side of number two and five crankshaft cheeks.

3. Spray the red spot­check penetrant into a cup.

4. Using an acid brush or equivalent, brush the spot­check penetrant on the aft side of the number two and five crankshaft cheeks. Ensure that the outboard area next to the counterweights is covered. See Figure 2, 3 and 4.

5. Allow the penetrant to dwell for 15 minutes before removing.

6. Remove the penetrant by spraying a soft lint free shop towel sparingly with spot check remover and wining. the penetrant off the number two or five crankshaft cheek. Do not spray remover on the cheek.

7. Protect the counterweight pins and bushings from the developer spray by placing a piece of masking tape or equivalent over the counterweight retaining plates. See Figure 5.

8. Spray the aft side of the number two and five crankshaft cheek with white spot check developer. Allow developer to dry. See Figure 5.

9. Using a flashlight and mirror, inspect the aft side of the number two and five crankshaft cheeks in the area between the counterweight blade bushing holes at the edge break from the crankshaft cheek to the blade web. See Figure 2, 3 and 6.

NOTE: The number two and five crankshaft cheeks are machined surfaces. The presence of light surface machine marks is normal.

10. If no crack indications are noted, proceed to "RETURN TO SERVICE" section of this bulletin.

11. If an indication of a crack is noted, notify Teledyne Continental Motors at 334­4383411 ext. 8354.

RETURN TO SERVICE:

1. Clean the number two and five crankshaft cheeks of all spot­check developer residue using a soft shop towel dampened with spotcheck remover.

2. Ensure that all spot­check penetrant and developer is removed from the number one and three crankshaft connecting rod journals.

3. Remove masking tape from the counterweight.

4. Thoroughly clean the interior portions of the engine with solvent.

5. Ensure that no debris is left in the engine interior.

Failure to remove all debris from the engine interior will result in engine damage and possible failure.

6. Drain the engine oil into an approved container.

7. Apply 50­weight Aviation grade oil to the number one and three crankshaft connecting rod journals.

8. Position the number one and three connecting rod caps with bearing insert and bolts installed (position number facing up) on the respective crankshaft connecting rod journals.

9. Install the number one and three connecting rods, with bearing insert in place, on the respective crankshaft connecting rod journal while supporting the connecting rod cap and bolts.

10. Lubricate the threads of the connecting rod bolts and nuts with clean 50­weight aviation grade oil and thread the nuts onto the bolts.

NOTE: Spiralock nuts are free spinning self locking fasteners and thread freely onto the connecting rod bolt.

11. Torque connecting rod nuts to the torque value specified in Table 1 as follows.

For connecting rods using either P/N 643215 or P/N 654490 self­locking connecting rod nut (Spiralock Nut), torque to the value specified in Table 1. See Figure 7.

For connecting rods using P/N 628109 castlellated nuts and P/N629340 bolt, initially torque nut to the specified low limit in Table 1 or TCM Service Bulletin SB967B. If the cotter pin hole in the bolt and the castlellations of the nut do not align, set the torque wrench to the specified upper torque limit and continue to torque the nut until the castlellations align or the specified upper torque limit is reached. If the specified upper torque limit is reached before the castlellations align with the cotter pin hole in the bolt, the nut will have to be removed and a new nut installed and torqued as specified above.

12. Install new cotter pin in each nut and secure by seating cotter pin head in nut castlellations and bending one leg of the cotter pin up over the con­rod bolt and back toward the head of the cotter pin. Trim leg so that its end is centered with the center of the bolt diameter. Bend the other leg down and trim it­so that its end is mid way between the nut base and the nut castlellation. See Figure 8.

13. Prior to installing number one and three cylinders, ensure that the engine interior is free of any debris and tools.

14. Install a new cylinder base "O" ring on each cylinder.

15. Lubricate the exposed portion of the piston and piston pin on each cylinder with clean 50­weight aviation oil.

16. With the aid of an assistant, install number one and three cylinders in accordance with the TCM Maintenance Manual, Overhaul Manual and Service Bulletins.

17. Lubricate all cylinder deck stud threads, through bolt threads and nuts with clean 50 weight engine oil prior to installation and torquing.

18. Torque cylinder deck stud nuts and through bolt nuts to the value specified in Table 2.

CAUTION
Proper cylinder installation requires a multiple step torquing process. Cylinder base stud threads, through bolt threads and nuts must be lubricated with clean 50­weight aviation oil.

a. Torque cylinder base nuts to 1/2 of the specified torque value for the fastener.

b. Torque the cylinder through bolt nuts and cylinder base stud nuts to the specified torque value for the cylinder base stud nuts. Through bolt nuts must be torqued on both sides of the engine.

CAUTION
Failure to torque through bolt nuts on both sides of the engine can result in a loss of main bearing crush, main bearing shift and engine failure.

c. Torque through bolt nuts on both sides of the engine to the specified value for the fastener.

d. On engines which incorporate the 7th cylinder deck stud, install the 7th stud cylinder bracket and conical stud nut. Torque the stud nut to the value specified for the fastener.

NOTE: Through bolt nuts P/N's 634505 and 649496 have been superseded by nut P/N 652541. Nut P/N 634505 is a flanged 6 point (hex) nut requiring a torque value of 690­710 inch pounds. Nut P/N 649496 is a flanged 6 point (hex) nut requiring a torque value of 790­810. Nut P/N 652541 is a flanged 12­point nut requiring a torque value of 790­810 inch lbs. At engine overhaul all P/N 634505 and 649496 flanged through bolt nuts must be replaced with P/N 652541 flanged 12 point nuts. If replacing PIN 634505 or 649496 nuts in less than a complete set prior to engine overhaul torque nut P/N 652541 to the required value of the original fastener (P/N 634505 or 649496).

19. Reinstall all engine components and baffles removed to facilitate this inspection in accordance with the aircraft manufacturer's maintenance manual.

20. Remove and replace the engine oil filter.

21. Reinstall the oil sump drain plug with a new gasket; torque to the specified torque and safety wire. On engines equipped with an oil sump quick drain, close the quick drain.

22. Service the engine with the correct type and grade of oil.

23. Perform a complete engine ground run up and ensure the engine meets the manufacturer's specified operations limits.

24. Thoroughly inspect the engine for oil and fuel leaks, broken, missing or loose hardware.

25. Correct all discrepancies prior to returning the engine and aircraft to service.

26. Make a logbook entry indicating compliance with this inspection.

WARRANTY

Warranty claims for labor and material used to comply with this Special Service Instruction (SSI 99­1) must be submitted to your TCM Distributor.

TCM will allow 15 man­hours of labor to comply with this Special Service Instruction.

All warranty claims must have a copy of the repair work order attached. Failure to attach a copy of the repair work order will delay the processing of your warranty claim.

FIGURE 1
CONNECTING ROD IN POSITION FOR REMOVAL

FIGURE 2
FOCUS INSPECTION IN THIS AREA

FIGURE 3
CRANKSHAFT IN INSPECTION POSTION
CONNECTING ROD REMOVED

FIGURE 4
APPLYING SPOT­CHECK PENETRANT
USING ACID BRUSH

FIGURE 5
CRANKSHAFT CHEEK AFTER APPLICATION
OF SPOT­CHECK DEVELOPER

FIGURE 6
INSPECT CRANKSHAFT CHEEK IN THIS AREA

TABLE 1
CONNECTING ROD TORQUE
(FROM SB 96­7B)

FIGURE 7 .
12 POINT SPIRALOCK NUT

FIGURE 8
CASTLELLATED NUT WITH COTTER PIN INSTALLED

TABLE 2
CYLINDER STUD NUT AND THROUGH BOLT NUT TORQUE