SAFARI

ENGINE

Fig. 6

Fig. 7

Fig. 8

PISTONS AND CONNECTING RODS

REMOVAL

(Cylinder head and oil sump removed)

1 Carefully remove combustion residues from top

end of cylinder bores, preferably by a broken

piston ring. Cut ridge by ridge cutter.

2 Turn crankshaft and bring a pair of pistons to

bottom most position. Unscrew their connecting

rod cap mounting bolts Fig. 6 and remove caps

with bearing shell. Turn crankshaft to bring this

pair of pistons and connecting rod to top most

position. Push these piston assemblies-out of

bores one by one using mallet wooden handle.

Remove remaining pistons in same manner.

NOTE :

Keep connecting rods and caps in sets. Preferably

assembleconnectingrodsandtheir capsafter removal

so that chances ofmixing/damageareavoided. Verify

serial numbers on cap and connecting rod.

3 Remove piston pin circlips with a suitable plier Fig. 7.

4 Remove piston pins with drift, 312 58913 39 (it is

advisable todippiston inhot oil at 70degC to 80deg

C before forcing piston pin out, if pistons are to be

reused).

5 Keep piston and piston pins in sets.

6 Remove connecting rod bearing shell and dulymark

them in case these are to be reused.

SELECTION OF PISTONS AND REPLACEMENT OF

PISTON RINGS

1 Remove piston rings from piston using piston ring

expander Fig. 8.

2 Remove carbon deposit and clean pistons/rings

thoroughly.

3 In case cylinder bore taper and ovality is within

specified limit, same piston/rings may be reused.

However, piston and rings should be examined

thoroughly for following:

a. Piston - Cracks, scoring, other damages, ring groove

wear,wear of piston pin bore in piston,circlip groove

wear/damage.

b. Piston rings - Scoring, lateral clearance in piston

ring grooves Fig. 9 and butt clearance (ring gap)

in cylinder bore Fig. 10 (this is to be checked in

unworn portion of the cylinder bore).

c. Piston or rings with any of the above referred

defects should be replaced.