Checking cylinder bores (VW Transporter T3)

The clearance between the cylinder and the piston can be determined by measuring the cylinder and piston separately. It is not possible to measure this clearance with a set of feeler gauges.



To measure a cylinder, a dial indicator is required for measuring internal dimensions, the scale of which should be pre-set to a specified value (see table).



Insert the feeler gauge approximately 10-15 mm below the inner edge.

If the piston and cylinder measurements show that the gap is about 0.2 mm, the piston and cylinder are replaced with a pair of the same size group. The difference in piston weight in the engine should not exceed 10 grams. A piston whose corresponding cylinder shows signs of wear cannot be replaced separately. If, on the contrary, the cylinder of the damaged piston shows no signs of wear, it is often sufficient to install a new piston of the same size group.

Note: The engine must be equipped with cylinders and pistons of only one size group. When deciding to replace pistons and cylinders, oil consumption plays a more significant role in addition to signs of wear. If oil consumption exceeds 1 l/1000 km, a major overhaul of the engine is required.