The Mercury Marine Mercury Seal 26-88397 is a water tube seal for use on various Mercury/Mariner outboard & Mercruiser stern drive engines.
 
Often referred to as the Race, Large, or Big Water pump Tube found on all Speedmaster SSM #4 (IV),  Sportmaster, and Torquemaster lower units as well as some SSM #6 and many sterndrives.
 
This seal fits on both sides of the water tube, top (motor water exit exhaust plate), and bottom (water pump housing), 
 
Part Numbers
26-88397
 
Included one (1) Mercury Big Tube Water Tube Seal Grommet.
 
Contact mike@buckshotracing77.com