Diesel Engine - Normal Cylinder Head Cracking
Number: 84-80Section: 6A (VI)
Date: Feb., 1984
Subject: CRACKED CYLINDER HEADS ON
4.3L V6 AND 5.7L V8 DIESEL ENGINES
Model and Year: 1978-84 IMPALA, CAPRICE, MONTE CARLO, MALIBU, EL CAMINO, CELEBRITY AND C-10 TRUCK
TO: ALL CHEVROLET DEALERS
We continue to hear about diesel cylinder heads being replaced because of cracks between the intake and exhaust valve seats. Cracks in the seat area are normal for both the 5.7L and 4.3L diesel as well as some other diesel engines produced by other manufacturers. Many cylinder heads that have been returned have been examined and the cracks are superficial. The coolant is approximately five-eights of an inch away from the crack and therefore will not result in a loss of coolant or compression. Refer to Dealer Technical Bulletin 81-T-40 for additional information.