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Polyurethane U-Seal, 3.38 Inch OD, 3.00 Inch ID, 0.19 Inch Height
Brand
Hercules Sealing Products
Brand
Hercules Sealing Products
Supplier Part Number
U18-3.00
Alternate Part Numbers
Alternate Part Number
C1DN79
got a cylinder groove that measures 3.00 on the ID and about 3.38 on the OD, is this the right u-seal size?
Question by: Cody B on Jul 21, 2025, 5:17 PM
Fit comes down to the seal dimensions, and this one is sized at 3.00 inch ID, 3.375 inch OD, with a 0.1875 inch height and cross section.
Answer by: Customer Support on Jul 23, 2025, 11:28 AM
Got a cylinder bore running 3 inch ID, will this u-seal drop right in, or is there more to fitment than just matching the ID?
Question by: Brenda C on Jan 20, 2026, 7:50 AM
For a standard u-seal installation, you need the ID, OD, and height to all match your gland dimensions. This one runs 3.00 inch ID, 3.375 inch OD, and 0.1875 inch height, so as long as your gland is cut to those specs, you're in good shape. If the groove depth or width is off even a little, you'll get bypass or premature wear, so it's worth double-checking all three dimensions before you seat it.
Answer by: Customer Support on Jan 22, 2026, 6:06 AM
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