2. Fitting pistons

Turn the block right way up and check the ring gaps in the bore - here they are spot on the lower limit - 12 thou compression rings, 15 thou oil control rings.

These are County brand pistons and rings.

The pistons are now ready to be fitted to the con rods ...........
...... note the oil sqirt hole in the conrod and the arrow on the piston that faces forward in the engine, so the oil squirt hole is on the OPPOSITE side of the engine to the camshaft.
Here you can see the side of the piston designed to take the thrust of fitting the gudgeon pin - this seat fits on a support ring in the press.
Here the gudgeon pin is being pressed into place - note the support ring below - the press shows a healthy 3 tons of pressure required to push the gudgeon pin into the con rod small end.
Components of the oil control ring - the octagonal expander ring, the wavy separator ring and the two thin scraper rings.
Expander first......
.... followed by the separator and the first of the the scraper rings, these are very flexible and can be sprung into place easily.
All in place!
Here you can just make out the word "top" in white near one end of the second ring - this ring is stepped and must be fitted this way up.
The top ring is symmetrical and can go in either way up. Support the ring in the fingers of both hands and use your thumbs in the gap to gently open the rings and slip them over the piston. Take care not to scratch the soft ally!
Fit the big end shells to the con rods and their caps, check the running clearance and coat the shells with Graphogen. Oil the piston - especially the ring grooves, and fit the ring compressor like this.....
... drop the piston into its bore.....
..... tap the compressor down against the block.........
..... and, holding the compressor in place, tap the piston down into its bore.
One done - three to go........
......  there, that was easy!


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