Kockney Koi 1½ Inch Threaded Blanking Cap with O-Ring

Kockney Koi 1½ Inch Threaded Blanking Cap with O-Ring

This Kockney Koi blanking cap closes a compatible 1½ inch male BSP connection. It is designed for the threaded end of the Kockney Koi 158 tank connector and includes the O-ring that forms the seal. The cap is useful when an outlet needs to remain closed, while leaving the option to reopen the connection later.

Unlike a solvent-weld end cap, this fitting screws onto the matching thread. It is not glued over the end of a pipe. That distinction matters when you are ordering fittings for a filter chamber, water tank or pond-building project: two items described as a 1½ inch end cap can have completely different connections.

Specification and identification

Brand	Kockney Koi
Manufacturer part	002807
Barcode	5031589002807
Connection	1½ inch female BSP thread
Intended matching fitting	Kockney Koi 158 tank connector
Seal	O-ring included
Pack	One cap with O-ring

Where to use a removable blanking cap

A tank or filter may have an outlet that is not required in its present layout. A correctly fitted blanking cap closes that connection without permanently bonding a plug into it. It can also be useful while planning a future pipe connection, provided the unused outlet and cap remain accessible for inspection.

Choose the cap around the actual tank connector rather than the approximate diameter of its hole. Our black waste threaded tank connectors include different sizes and designs, so select the matching Kockney Koi option and check its sealing face. A cap cannot compensate for a damaged connector, distorted thread or unsuitable sealing arrangement.

Check the thread and sealing face

The manufacturer specifies a female BSP thread. The mating fitting must therefore have the appropriate male thread. Nominal BSP sizes describe the thread standard; they are not a promise that the outside diameter of the thread will measure exactly 1½ inches. Measuring roughly across the fitting is not enough to establish compatibility.

The O-ring also needs the correct surface to seal against. Although another fitting may accept the thread, its shape may not provide the right seat for this cap. Check the complete connection before fitting. If the existing part has a different thread, a tapered connection or a damaged sealing face, choose the fitting intended for that component instead.

Preparing the connection

Isolate the relevant water route and remove pressure or water head before removing an existing cap. Switch off equipment that could unexpectedly restart the flow. If the outlet is below water level, establish how you will prevent the tank or pond draining before opening it. A blanking cap is not an isolation valve and does not let you control a live flow while it is being removed.

Clean dirt from the mating thread and sealing face, then inspect them for damage. Check that the supplied O-ring is present, clean and correctly seated. It should not be twisted, trapped across the thread or stretched out of position. An old or damaged seal should not be reused simply because the cap can still be screwed on.

Fitting and checking the seal

Start the cap squarely by hand so the thread engages without crossing. The manufacturer describes the O-ring as the sealing component, so additional sealant is not normally needed for the intended connection. Solvent cement must not be used on a joint intended to unscrew, and thread tape is not a replacement for the supplied O-ring.

Do not use excessive force to overcome resistance. If the cap will not engage normally, stop and check the thread and alignment. Once fitted, restore water gradually and inspect the joint for leaks. Keep the connection visible during this check rather than immediately enclosing it behind equipment or covering it with backfill.

Planning access and future changes

Leave enough space to reach and remove the cap later. A removable fitting is less useful if a wall, filter frame or new pipe run prevents it turning. Where the installation needs regular opening for maintenance, consider whether a suitably specified valve would be more convenient. Our Kockney Koi black waste ball valves provide flow isolation in compatible pipework; this cap simply closes an end connection.

If the outlet will later connect to rigid pipe, plan the transition separately. A black waste split connector can provide a removable join in the pipe run, but it serves a different purpose from this threaded cap. Check every thread, socket and pipe standard before assembling the final route.

Choosing the right type of end cap

For closing a plain solvent-weld pipe rather than a threaded tank connector, compare our black waste end caps. These fittings must match the relevant pipe system and are not direct replacements for the O-ring cap. Rubber stop ends and pressure-pipe caps are also separate designs, each with its own connection requirements.

Keep the part number with your maintenance notes so a replacement can be identified accurately. Inspect the cap and seal whenever the connection is opened, and check for seepage as part of normal filter maintenance. No pressure rating or universal equipment compatibility is claimed for this cap: use it within the intended tank-connector arrangement and the requirements of the complete installation.