SERVICE ENGINE ASSEMBLIES PARTS BOOK REV. FOR HT4100

Should it become necessary to replace an entire HT4100 engine assembly due to a major failure, complete "Service Engine" assemblies are available from General Motors Service Parts Operations (GMSPO). Applications and instructions for all available engines are described in Serviceman Bulletin T-87-13. The part numbers for these service engine assemblies all begin with numbers 363XXXX. The September 1986 revisions to the parts catalogs do not list all the appropriate part numbers listed in Bulletin T-87-13. This will be corrected in the next revision of the parts catalog. In the mean time, the correct assemblies can be obtained by referring to Bulletin T-87-13.

This omission is complicated by the fact that the September 1986 parts book revision does list some part numbers for a different variety of HT4100 engine assemblies. These units all begin with part numbers 351XXXX and include additional parts to those included with the 363XXXX service engine assemblies which results in a considerably higher price. These 351XXXX "production engine" assemblies must not be used for warranty repairs. Claims submitted for these assemblies will be rejected and require zone approval.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.