How To Install A Welch Plug

Replacing disc type core plugs "Freeze plugs"

Volvo 140, 164, 121, P1800, PV, 200, 300, 700, 900

22.12.2021

We show the renewal of a disc blazon cadre plug "freeze plug" with simple tools. The repair has been done on a Volvo B20 engine block.Please note that these instructions tin can only be used for disc type frost plugs. In the case of cylindric plugs, it must be noted that the core hole has no inner edge where the frost plug rests. Therefore, the plug may accidentally fall into the engine block during the process shown here.

Water leakage caused by a broken plug.

Drain the engine block.

The older Volvo petrol engines take a drain tap adjacent to the oil filter. This is merely opened with an open-end wrench. Identify a hose on the tap to channel the cooling water into a collection container.

Hammer a chissel or a durable screwdriver through the broken plug. A brusque and heavy hammer is a proficient pick. Caution: Do not hammer in too far!

Lever out the cleaved plug.

Clean the sealing surface at the engine block.

Utilise some sealing compound to the sealing surface. Put in the core plug with curvature outwards.

The disc cadre plug is spread by deformation / "flattening" of the curvature and thus clamps itself.Use a brusque and heavy hammer and a pressure piece which has approximately half the diameter of the core plug. We used a brusk, solid brass rod.Put the pressure level piece direct on and endeavour to flat the curvature with ane single blow if possible.

All notes serve simply as an example and exercise not supplant the workshop instructions of the car manufacturers! All data is supplied without guarantee!