Self-aligning Shaft Seal | ISB-SA Combo w/Bearing

Self-aligning Shaft Seal | ISB-SA Combo w/Bearing

$1,769.48$4,774.92

The perfect upgrade for boats with traditional bronze stuffing boxes.  Our self-aligning shaft seal is attached to an intermediate shaft bearing (in place of existing stuffing box) offering improved safety and reliability over other “dripless” and “packless” style mechanical shaft seals.  Proven performance for today’s higher horsepower commercial and recreation boats with less noise and vibration.

NOTE: Packing Sold Separately

(We recommend Duramax Ultra-X)

Download: Product Sheet [PDF]

Installation Tip: The intermediate shaft bearing (ISB) mounts in place of a traditional stuffing box and our SA-Series self-aligning shaft seal attaches to the barbed end of the ISB bearing.

Product Details

Product Description

Upgrade your stuffing box with an R.E. Thomas Marine Hardware’s self-aligning shaft seal with intermediate bearing housing featuring Johnson Cutless Bearings.

Product Video:

Here’s how it works:

The bearing housing mounts in place of your boat’s stuffing box flange and the packing nut assembly (shaft seal) self-aligns on the shaft by way of a heavy duty flexible hose.

There’s also a hose barb connection to your boat’s raw water pump to keep the unit cool and the cutless bearing lubricated.

Our self-aligning shaft seal combines the benefits of a “dripless” mechanical seal with the bullet proof reliability and performance of a traditional bronze stuffing box.

Less Vibration and Noise PLUS A Drier Bilge

Simply put, our heavy duty self-aligning shaft seal is the safest and most dependable shaft sealing device on the market and is ideal for high horsepower commercial and recreational installations.

R.E. Thomas Shaft Seals vs Dripless/Packless Shaft Seals

  • No rubber bellow to tear or lose compression and cause flooding.
  • No stainless rotor to slip on the shaft and cause flooding.
  • No carbon stator (sealing face) to crack and cause flooding.
  • No cheap nylon hose fitting to snap or break off and cause flooding.
  • No o-ring or lip seals to fail and cause flooding.

What if Your Boat Has A Shaft Tube?

The ISB-SA Combo shaft sealing system is designed for boats with traditional bronze stuffing boxes.  If your boat has a shaft tube (i.e. stern tube or shaft log), refer to our SA Series self-aligning shaft seals that are designed to mount directly to your boat’s shaft tube (stern tube) without the need of an intermediate shaft bearing.

Sizing and Specifications:

Refer to our size chart below for mounting flange sizing and specifications.

Note: Mounting flanges can be cut down for installation in boats with limited room such as “Downeast” style boats.

Specifications | Sizing Chart

sizing the right stuffing box

Installation Video