Cutlass Bearings for a 4" Shaft
We list two Exalto cutlass bearings for a 4" (101.6 mm) propeller shaft, in phenolic and brass. They fit a 5" (127 mm) housing bore, and both are 16" (406.4 mm) long. The nominal wall is 12.7 mm thick: half the difference between housing bore and shaft.
Of these, one is in Australian stock (the phenolic IPSF32), with same-day dispatch on orders placed by 2pm AEST on a business day. You can pre-order the other one, with dispatch estimated at 3 to 4 weeks. Prices run from $1,300.00 (the phenolic IPSF32) to $2,395.00 including GST, and Express Post delivery within Australia is free.
A 100 mm (3.937") shaft is only 1.6 mm smaller, but its bearings are a different nominal size and are not interchangeable with these. Check which unit your shaft was made to before ordering, or see the bearings for a 100 mm shaft.
2 bearings for a 4" shaft
How to choose a bearing for a 4" shaft
Measure the housing bore and the length of the bearing you are replacing, then find that combination below. Every bearing here shares one housing bore and length; they differ in shell material, tolerances and availability.
- 5" (127 mm) housing, 16" (406.4 mm) long: phenolic IPSF32 (in stock, $1,300.00), brass IBSF32 (dispatch in 3 to 4 weeks, $2,395.00)
Phenolic and brass describe the outer shell, and each has a grooved nitrile rubber lining. The non-metallic phenolic shell avoids galvanic corrosion between the shell and a metal housing. Exalto advises against fitting brass directly into steel or aluminium housings. More about each: phenolic cutlass bearings and brass cutlass bearings.
Matching sizes is the first check, not the last: confirm the shell material, the housing's condition and the retention method for your boat. The measuring guide explains what to record, or contact us with your measurements.