V8 Gasoline (AJ133) Cylinder Head To Block Bolts Do Not Fit Through Head (SSM61197)

WARNING: This page is about the LR4 Base, which is a different variant/trim than selected.

Publication date: 2015-01-05
Reference number: SSM61197

V8 GASOLINE (AJ133) CYLINDER HEAD TO BLOCK BOLTS DO NOT FIT THROUGH HEAD

TECHNICAL SERVICE BULLETIN

Reference Number(s): SSM61197, Date of Issue: January 05, 2015

LAND ROVER:	Discovery 4 / L319; Range Rover / L322; Range Rover Sport / L320
SECTION:	Engine

SERVICE INFORMATION

Symptom 499000 Basic Engine

ISSUE

When fitting cylinder heads onto an AJ133 (V8 gasoline) cylinder block, the bolts that secure the head to the block will not fit through the holes in the cylinder head. This could happen if cylinder heads from the original engine are fitted onto a new cylinder block or short / stripped engine.

CAUSE

The AJ133 cylinder block design changed from using a 10mm bolt to an 11mm bolt in 2009. Since then service has been supplying both 10mm and 11mm bolt designs of the cylinder blocks. However, the supply of the '10mm' design blocks will soon end and only the 11mm bolt design blocks will be supplied.

If the holes in the cylinder head are at the minimum engineering tolerance, and the bolt is at the maximum engineering tolerance, there is a chance the bolt will not fit through the hole in the cylinder head.

ACTION

If the cylinder head to block bolt does not fit then the cylinder head bolt holes diameter can be increased by up to 0.25mm, to a maximum diameter of 11.1mm.

The cylinder head bolt holes diameter can be increased by using a hand reaming tool. If necessary the holes can be drilled, but this work should be done at a suitable machine shop.

It is vital that the cylinder head is completely clean of any debris from the reaming / drilling work before the heads are fitted to the engine.