Volkswagen Golf/Jetta 2 manual

Cylinder block/crankcase - examination and renovation
Engine repair procedures - 1.05 and 1.3 litre pre August 1985 / Cylinder block/crankcase - examination and renovation

1 The cylinder bores must be examined for taper, ovality, scoring and scratches. Start by examining the top of the bores. If these are worn, a slight ridge will be found which marks the top of the piston ring travel. If the wear is excessive, the engine will have had a high oil consumption rate accompanied by blue smoke from the exhaust.

2 If available, use an inside dial gauge to measure the bore diameter just below the ridge and compare it with the diameter at the bottom of the bore, which is not subject to wear. If the difference is more than 0.15 mm, the cylinders will normally require reboring with new oversize pistons fitted.

3 If cylinder bore wear does not exceed 0.20 mm, special oil control rings and pistons can be fitted to restore compression and stop the engine burning oil.

4 If new pistons are being fitted to old bores, it is essential to roughen the bore walls slightly with fine glasspaper to enable the new piston rings to bed in properly.

5 Thoroughly examine the crankcase and cylinder block for cracks and damage and use a piece of wire to probe all oilways and waterways to ensure that they are unobstructed.

6 Check the core plugs for leaks and security (see illustration)

22.6 Core plugs in cylinder block
22.6 Core plugs in cylinder block

© 2019 All Rights Reserved.