Dnepr MT10-36 - Connecting Rods Assembled with Bushings; Piston, Piston Rings and Piston Pins

the case of major repairs, it is recommended that the
crankpin bear i ng bushings be replaced . This will pro-
tect .the crankpins from pr . ematur .e wear.
Connec tin g R.ods Assembled wit h Bush ings
The connecting rods are steel, forged, having an
I -shaped cross-section. Pressed into the connecting rod
small end is a bronze bush i ng whose opening is made
with a great accuracy to ensure the correct fitting of
the piston pin . The big end of the connecting rod is de-
tachable, not symmetrical, with ~ hin - wall'ed interchan-
geable bushings. For correct installing of t he connect-
ing rods on the crankshaft, the connecting rod blades
are provi.ded wit h lugs which must be directed out -
wards with respect to the crankshaft web (for the·right-
hand connecti ng rod, the lug should be directed to -
wards the flywheel; for the !·eft- hand · connecting rod,
towards the centrifuge) .
The
connecting rod caps are not interchangeable.
The
nuts of ·the connecting rod bolts <lire tightened up
and locked by cotter pins. The use · of old cotter pins is
inadmissible.
Piston, Piston R.ings and Piston Pins
Engine piston 15 (Fig. 5) consi sts of a spherical
head, skirt,
and bo sses. The piston is provided with
four groov
es in which the piston rings are fitt e d.
Two upper compression rings 14 provide the required
air - tightness of the cylinder, thus preventing the gas
ieakage from the combustion-chamber into the crank-
case. Two lower oil scraper rings 13 are used to remo-
ve
excessive oii from the cylinder walls.
The axis of
the piston pin hole is displaced by
1.5 mm from the piston centreplane. For 1his reason,
the
pis· ton moves smoothly, without shocks, within th e
clearance between the piston skirt and the cyl'inder
walls \ Vi hen the direction of movement is ohan ge d at the
upper dead centre. Fitted on the piston head is a poin-
ter to indicate the correct position of the piston in th e
cylinder.
When mounting, s~e that the pointer, on the
both pistons, is dir.ected forward, i. e. towards the
centrifug .e.
The piston ri
ngs are manufactured f·rom a special
grade of cast iron and are provided with straight
locks. When installing the piston with rings into the
cylinder, ensure that piston ring gaps are within 0.25
and 0.5 mm .
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