Electra Estate Wagon V8-350 5.7L DSL VIN N FI (1984)
Piston Pin: Technical Service Bulletins
Diesel Engine - Service Pistons
Bulletin 84-6-27
Date
April '84
Ref. No. 84-196-6
SUBJECT:
DIESEL ENGINE SERVICE PISTONS
MODELS AFFECTED:
1984 5.7L V-8 AND 4.3L V-6 ENGINES
PISTON PIN AND RETAINER
The piston pin and retainer have been changed for 1984 model diesel engines. This change utilizes a longer piston pin which is chamfered an each end,
along with a round wire retaining ring. To accommodate the round wire ring, the retainer ring groove in the piston has been changed from a square cut
groove to a rounded groove. It also contains a pry-out notch. (See illustration.)
Some service pistons now being used incorporate the round wire retainer. Eventually, all service pistons will. Goodwrench engines being produced now
also contain the rounded wire ring retainer.
Procedures for removing and installing the round wire ring are contained in the 1984 model service manuals. The service pistons used in past model
engines may contain both designs of retaining rings. It is important to remember that the pistons, piston pins, and piston pin retainers must not be
interchanged. Become familiar with each component. The round wire ring goes with the pin that is chamfered on each end and the piston has a pry-out
notch. The flat snap ring goes with a square end piston pin and the piston does not have a pry-out notch.
