Engine - Crankshaft Bearing Size, Manual Update

91mitsubishi03

NO. TSB-91-11-001

DATE February, 1991

MODEL 1989-90 V-6 Montero, Sigma

SUBJECT: V-6 CRANKSHAFT BEARING SIZE - SERVICE MANUAL UPDATE

TSB Revision TSB-91-11-001

PURPOSE

V-6 engines manufactured since 1988 incorporate an improved crankshaft design. This design change consists of an undercut fillet at the ends of the crankshaft journals, which increases the strength of the rod and main bearing journals, thereby increasing the durability of the crankshaft. Crankshaft machining is not recommended for these crankshafts since any grinding will alter the internal radius and reduce the strength of the crankshaft.

Since crankshaft machining is no longer possible, references made in the affected service manuals must be deleted.

INSTRUCTIONS

Please delete or change text in the affected service manuals as shown on pages 2-7 of this bulletin, and, as reference to this TSB, please write this TSB number in the TSB Revision boxes on the affected service manual pages.

NOTE: In the 1989 and 1990 Montero Service Manuals the "Taper of journal and pin" specification has been revised from 0.05 mm (.002 in.) to 0.03 mm (.0012 in.).

AFFECTED SERVICE MANUALS

AFFECTED SERVICE MANUAL PAGES AFFECTED

1988 Galant Sigma 9-8, 9-9, 9-74, 9-78, 9-79

1989 Sigma V-6 9-6, 9-66, 9-71

1990 Sigma V-6 11-6, 11-62, 11-66

1989 Montero 9-60, 9-102, 9-106

1990 Montero 11-101