Replacement O-Ring for TSP Aluminum Water Neck

• Replacement O-ring reseals TSP aluminum swivel-style water necks against leaks

• Simple drop-in swap — no cutting or special tools needed to reinstall

• Fits TSP swivel aluminum necks SP8455, SP8456, SP8457, and SP8459 (black & polished)

• Precise 1.970" ID / 2.300" OD / 0.165" thick sizing matches the factory seal

This replacement O-ring reseals TSP's aluminum swivel-style Chevy V8 water necks when the original seal wears, hardens, or starts leaking coolant at the thermostat housing connection. It's sized to match the factory seal exactly — 1.970" inside diameter, 2.300" outside diameter, and 0.165" thickness — so it drops into place without modification.

This O-ring is designed for TSP's swivel-style aluminum water necks only — SP8455, SP8455BK, SP8456, SP8456BK, SP8457, SP8457BK, SP8459, and SP8459BK. It is not designed for TSP's zinc/chrome fixed-outlet water necks, which use a different sealing configuration.

Compatible Water Necks
This O-ring fits TSP's swivel-style aluminum water necks in both black and polished finishes: SP8455, SP8455BK, SP8456, SP8456BK, SP8457, SP8457BK, SP8459, and SP8459BK, covering the straight, 15°, 45°, and 90° outlet angle versions.

Installation
Remove the water neck from the thermostat housing, clean the old O-ring groove of any hardened seal material or debris, and seat the new O-ring evenly before reinstalling. A properly seated O-ring should sit flush in the groove with no twist before the water neck is torqued back down.

What water necks does this O-ring fit?
This O-ring fits TSP's swivel-style aluminum water necks: SP8455, SP8455BK, SP8456, SP8456BK, SP8457, SP8457BK, SP8459, and SP8459BK. These include straight, 15°, 45°, and 90° versions in polished and black finishes.

Will this fit the zinc/chrome water neck with the NPT port?
No — the SP7240 water neck uses a different fixed-outlet sealing design and is not compatible with this O-ring.

How do I know if my water neck's O-ring needs replacing?
Replace the O-ring if you notice coolant seepage at the thermostat housing, cracking, hardening, flattening, or other visible damage. Replacement is also recommended whenever the water neck is removed for service.

Do I need any tools or sealant to install this O-ring?
No special tools or sealant are required. Clean the O-ring groove and sealing surfaces, seat the new O-ring evenly, and reinstall the water neck according to the proper tightening procedure.

Can I reuse my old O-ring after removing the water neck for service?
It's not recommended. O-rings can become compressed or hardened after installation, so installing a new O-ring whenever the water neck is removed helps reduce the risk of coolant leaks.