380SL (107.045) V8-3.8L (116.960) (1982)
Piston Ring: Service and Repair
Special tool
Piston ring spreader
000 589 51 37 00
NOTE: If piston rings are renewed, the cylinder wear and the piston ring axial clearance must be measured with new piston rings.
1
Take off old piston rings; remove carbon from piston crowns and top lands.
2
Remove carbon from piston ring grooves; do not use sharp tools to avoid damaging corners of grooves.
3
Clean oil drain drillings in the oil ring groove.
Piston with taper face compression ring
NOTE: Pistons with a different 2nd piston ring (taper face compression or taper face hook scraper ring) may be installed in an engine. The 2nd
piston ring must be replaced with a ring of the same shape otherwise it will jam tight in the groove.
The 2nd piston ring can be properly matched by means of the piston code no., e.g. "64" in the piston crown and the piston part no., e.g. 117 030 64
17 and the piston ring set for this piston.
Piston with taper face hook scraper ring
4
Install 3rd piston ring (oil scraper ring). The joint of the inside spiral spring must be positioned opposite the lint of the piston ring. Install 2nd
piston ring. Pay attention to shape of ring. Install 1st piston ring.
CAUTION: Inscription, e.g.. "TOP", on piston ring must be positioned facing up.