Why are my cam chain tensioners breaking on my Jaguar?
(The new 4.2L version of the Jaguar AJ-V8 engine has double timing chains.) As a result of their weak design and other factors like engine overheating or poor maintenance, the plastic cam chain tensioners on 1997 to 2000 V8 Jaguars began to experience stress fractures, and so did some of the plastic guides.
What kind of tensioner do you use on a Jaguar V8?
(See the photos at left.) We now use the metal-based third-generation tensioners exclusively when replacing cracked first- and second-generation Jaguar V8 tensioners. When a plastic tensioner shatters or wears to the point the cam chain becomes loose, a rattling around can be heard in the cam area at the front of the engine.
How much does it cost to replace a tensioner on a Jaguar?
When the cars were under warranty, rattling tensioners, or failed engines due to tensioner breakage, would be replaced with beefed-up second-generation plastic tensioners at no charge to the owner.
When did the Jaguar tensioner Bulletin come out?
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.
What was the problem with the chain tensioner on my 1998 Jaguar?
Nalley of Roswell, GA, Thsi tensioner thing is a real problem. I have a 1998 VDP with the 4.0 liter engine. With the car out of warranty and with 69000 miles on the engine, one of the chain tensioners failed, resulting in one of the valves punching through a piston.
(See the photos at left.) We now use the metal-based third-generation tensioners exclusively when replacing cracked first- and second-generation Jaguar V8 tensioners. When a plastic tensioner shatters or wears to the point the cam chain becomes loose, a rattling around can be heard in the cam area at the front of the engine.
How does a chain tensioner work on a JAG?
That’s an expensive failure. Gwen – The Jag V8 you have uses a chain drive (like a bicycle chain) to drive the cams that open and close the engine’s valves. The tensioners keep the chain tight so it doesn’t flop around; they work like the spring loaded derailleur on a bike.
Are there any issues with the Jaguar XJ8?
Verified HelloIn 2000 there was an upgrade to the timing chain tensioners and another one in 2001 this was in addition to the change over to cast iron liners in the engine block as well. So yes a 2002 model should be fine and there are no other recorded issues for this year.
When to get a tensioner replaced on a Jaguar XJ8?
If you would like us to do a tensioner replacement under third-party warranty, please supply us with contact information about your warranty provider before we start the job. We recommend that if your XJ8/XK8 has passed 35,000 miles, you take preventive action and have the tensioners inspected.
Can a loose tensioner cause a cam sprocket to fail?
As the tensioners wear, the cam chains can become loose and eventually jump one or two teeth on the cam sprockets – usually on a cold start. If the chain jumps one tooth, rough running will be experienced. If it jumps more than one tooth, the valves on one block will contact the pistons, resulting in engine failure.
Can a 1999 XK8 have chain tensioner problems?
This topic is for discussion of chain tensioner problems on some of the older XK models, and how you deal with them. 1997-1999 XK8s can suffer from timing chain tensioner problems. A 2000 model would be better while 2003-2006 are the best. 2003 XKs had over 900 changes. I just spent $4200 to replace the tensioners, chains, etc on my 1999 XK8.
How much does it cost to replace chain tensioner on Jaguar XK?
Part of my sale included resolution of all existing mechanical issues. One of the mechanical symptoms was: when the engine was cold there was a valve ticking noise. Sure enough, the timing chains, tensioners, blade, guide, several seals and gaskets were replaced. $840 for parts, $1,300 for labor. Warranty paid for it all!
(The new 4.2L version of the Jaguar AJ-V8 engine has double timing chains.) As a result of their weak design and other factors like engine overheating or poor maintenance, the plastic cam chain tensioners on 1997 to 2000 V8 Jaguars began to experience stress fractures, and so did some of the plastic guides.
What should I do if my chain tensioner fails?
With the car out of warranty and with 69000 miles on the engine, one of the chain tensioners failed, resulting in one of the valves punching through a piston. There was no ‘noisy engine’ symptom prior to the failure. The dealer’s recommended fix was a new crate engine at a price of about $9K.
How long does it take to replace Jaguar tensioners?
We only use Jaguar’s third-generation metal tensioners. Should you elect to replace your tensioners, make an appointment and we normally have a 48-hour turnaround. Our 12-month, unlimited mileage warranty will apply to all parts and labour. Could you experience the problem with the new tensioners after replacement is carried out?
What’s the difference between double and single chain Jaguar?
These plastic components are part of the AJ-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. (The new 4.2L version of the Jaguar AJ-V8 engine has double timing chains.)