Exchange Of Piston Rings; Exchange Of Piston Pin Bearing In Connecting Rod - Bukh DV36/48 Workshop Manual

Exchange of Piston Rings

The piston ring gap is 0.3 – 0.45 mm (0.0118 - 0.0177 inch) in a new engine.
The wear of the piston rings ca n be seen by measuring the piston ring gap, and the piston rings
must be changed when this is max. 2.0 mm (0.0787 inch).
This is done as follows:
1. Take out the piston with connecting rod as stated on page IJ 3.
2. Remove the piston rings either by a spec ial pair of tongs or by m eans of two piec es of
string which have been folded. With the clos ed ends around the ends of the piston rin g,
the piston ring is extended and can be lifted clear of the piston.
The mounting is carried out in the reverse order
cleaned. Rotary steel brushes or a steel scrapers should not be used as cleaning tools.
Each piston has three piston rings: two compre ssion rings and one oil scraper ring as shown
on the drawing page IJ4. The upper compre ssion ring are shown on page IJ 7 the lower
compression ring is a so called M-ring and the oil scraper ring is shown on page IJ8.

Exchange of Piston Pin Bearing in connecting rod

If heavy wear of the piston pin bearing in the connecting rod is found, it may be necessary to
exchange it. Particular attention should be paid when exchanging, as the bearing must be calibrated
to correct roundness and clearance after the fitting. This is either done with a calibration ball, as
indicated on page IJ10, or with a reamer with the tolerance mentioned.
009W2329-R01
after the piston ring grooves have been
IJ9