If upon start-up you notice a rattling sound from your 1997-2002 Jaguar V8 engine, or unusually rough running, turn off the engine immediately and DO NOT restart it. Have the car towed to us, NP IMPORTS, for inspection. 770-640-0077
Jaguar’s 4.0-liter V8, was the first-ever eight-cylinder engine from that manufacturer. In their zeal to reduce the weight of the valve train and related components as a way of improving fuel efficiency, the engineers underdesigned its timing gear: in particular, the cam chain tensioners. These plastic components are part of the V8's single-chain design, a weight-saving alternative to the more robust double-chain approach Jaguar has used on most of its six-cylinder engines.
As a result of their weak design and other factors like engine overheating or poor maintenance, the plastic cam chain tensioners on 1997 to 2002 V8 Jaguars began to experience stress fractures, and so did some of the plastic guides.
In their Technical Service Bulletin No. X303-68 of February 2005, titled “Rattle From Engine on Start-up and Idle,” Jaguar states:
This Technical Bulletin has been issued to address customer concerns of a rattle emanating from the engine on start-up and idle.
Cause: Failure of a primary or secondary timing chain tensioner.
Should a customer express concern, and the fault has been confirmed as a timing chain tensioner, new primary or secondary timing chain tensioners must be installed.In 2005, Jaguar introduced a third-generation metal-based tensioner kit. We use the metal-based third-generation tensioners when replacing cracked first- and second-generation Jaguar V8 tensioners.
We recommend that you take preventive action and have the tensioners inspected. If they are cracked, have them replaced before it causes engine failure leading to costly repairs.
NP IMPORTS offers a Timing Chain Inspection for $95. If you decide to upgrade your timing gear we will deduct the $95 charge from your invoice. Call us and schedule an appointment today. 770-640-0070
