Engine - Knocking Noise
88cad02Bulletin No. T-88-78
File in Group 6A
Number 92
Corp. Ref. No. 636105
Date Jan. '88
SUBJECT: ENGINE NOISE CAUSED BY WORN PISTON PIN 2.0L-L4
MODELS AFFECTED: 1985-1986 CIMARRONS WITH 2.0L ENGINES
Some 1985-1986 Cimarrons equipped with 2.0L L4 engines may experience a knock-type engine noise. If this noise is identified as a crank speed internal reciprocating noise, the source may be caused by wear to the piston pin boss of the piston.
If the piston is suspected of causing a cold and hot noise complaint, then the piston/piston pin interface should be examined for wear, i.e. out-of-round or grooving. The service manual procedures in Section 6A should be followed for removal and inspection of the pistons and pins.
If wear conditions indicate a need for piston and pin assembly replacement, then one of the following new piston ,and pin assemblies should be used for the affected cylinder:
Standard Piston/Pin Assembly PN 10103570
High-Limit Piston/Pin Assembly P/N 10103571
0.5 mm Oversize Piston/Pin Assembly PN 10103572
1.0 mm Oversize Piston/Pin Assembly P/N 10103573
Select the piston/pin assembly by using the procedure described under "Piston Fitting" in Section 6A of the Service Manual for 2.0L engines.
For warranty purposes, use Labor Operation J1308 at 5.4 hours to replace one piston with an add time of .7 hour to replace each additional piston.