Service Manual 5008732_15-30 HP Midsection [Trim Tab Service]

Drain lubricant before testing.

Use Gearcase Pressure Tester, P/N 507977. Install lubricant drain/fill plug and seal, thread pressure test gauge fitting and seal in lubricant level hole.

Pressurize 3 to 6 psi (21 to 42 kPa).

If pressure gauge indicates leakage, submerge the gearcase in water to determine source of leak. If the gauge does not indicate leakage, increase pressure to 16 to 18 psi (110 to 124 kPa). Check for leaks.

Make necessary repairs and repeat test.

Install Gearcase Vacuum T ester, P/N 507982. Apply 3 to 5 in. of vacuum (76 to 127 mm) Hg. with pump.

If vacuum gauge indicates leakage, apply oil around suspected seal. If leak stops or oil is drawn in, seal is defective.

Repeat test, gearcase must h old minimum of 15 in. vacuum (381 mm) Hg.

Removal

Note where the index mark on the gearcase aligns with the index mark of the adjustable trim tab so the trim tab can be installed in the same position.

1. Index marks

Remove the trim tab retaining screw a nd trim tab from the gearcase.

1. Trim tab retaining screw

Apply Gasket Sealing Compound to threads of the trim tab screw. Install and align the trim tab with the index marks noted prior to disassembly. Tighten the trim tab screw to a torque of 60 to 84 ft. lbs. (7 to 9.5 N•m). For adjustment, refer to Trim Tab Adjustment on p. 27.