Captive nut for top left engine mounting bolt.

When converting to the dog house cooler and without switching out the tin, you can no longer access the nut to install and remove the engine. This captive nut was the VW factory solution.

This captive nut can be found on more modern Type-1 engine cases at the top left in the direction of travel. It belongs to the four attachment points from the gearbox to the engine.

Type-1 motors are attached to the gearbox with two bolts and two studs. While studs are used at the bottom of the case - which are secured with nuts on the gearbox side - bolts are used at the top. On the right side (in the direction of travel), this is a bolt with a semicircular head, which is secured in the engine compartment by a nut.

On the left side (in the direction of travel), a regular M10 bolt and nut are used in older models. However, if the hole in the housing is larger than an M10 thread, this captive nut must be used. It gets driven in from the engine case side and replaces the securing nut.

Fits:
Bug (Type 1): 71-79
Bus (Type 2): 71
Type 3: 71-74
Ghia: 71-74
Thing: 73-74