2000 s type 4.0. engine wud not start, will crank.Steve jaguar looked at it found secondary chain nd tensioner broken, stated,around 1200 for repair.Also suggested to replace other three chains and 3 tensioners.Is this a must or preventive maintenance? All extras are going to cost too.timing chains are 100 a piece.

I am in the understanding, you have replace timing belts on routine and not when it is a chain like old school cars. what is the jaguar take on time chain replacement? i was told the chain snapped because of the secondary tensioner failed, so with that will it suffice changing the poor quality tensioner only? ( TSB on this subject.)

 

The Jaguar AJ series engines are of a zero clearance design, so if one of the secondary timing chain tensioners fails causing the facing secondary chain to break, the cylinder head on that side will sustain severe damage due to the pistons striking the valves requiring the head to be removed from the engine.

There are several vendors who offer 'kits' to upgrade the timing chain tensioners, chain tensioner blades and chain guides along with new primary and secondary chains for around 1000$US. There are also several special tools involved with the procedure, which is outlined in the JTIS manual, a free download from this forum.

From your description, it seems there will need to be further disassembly required to determine the extent of damage. Another option, depending on the overall condition of the vehicle, is to find a second-hand engine to swap in.

 

+1 find a used engine and swap out tensioners and chains with new upgraded versions before installing. (if you plan on keeping the car) There are no belts - but chains. If the chain broke due to the tensioner failing - more than likely there is severe damage to the affected cylinder head/engine block to say it kindly.

 

Just because the chain broke DOES NOT mean the exhaust valves on that bank ARE bent, they MIGHT be bent. It all depends on where the exhaust cam stops when the chain stops turning the cam and where this piston was.

I have replaced the chain/tensioner assy on several engines that broke and the engine ran fine. The worst I saw was a chain that 'wadded-up' around the exhaust cam sprocket and pushed a 'chunk' out of the cylinder head (replacement head time!!!).

I usually pull the exhaust cam from the head and check the compression on that bank.
If you don't get a 'ZERO' reading, then install the chain/tensioner and start the engine????

I bought a 1999 XJ8 for $500 because the chain broke. I lucked-out, NO BENT VALVES!!!!!!

All you can do is diagnose and if the compression is not zero, then you are probably OK. IF ZERO, then 'HEAD-OFF'.

bob gauff

 

Thanks guys, my local Jag tech will check if the valves are bent on monday.Is there any way you can check if they are bent without removing exhaust cam? Is it better to buy a used engine or repair the broken head/valves?

 

Once the cam cover is OFF it takes 15 minutes to remove the exhaust cam??????

What reason would prevent the removal??????????????

I would pay the mechanic an extra hour to remove the cam and crank the engine!!!!!!

Compression test is only needed for that side???????

I guess I think too much.

It's called diagnosis.

bob gauff

 

Some are just lucky, the engines I looked at all had damaged exhaust valves when the secondary chain tensioner failed and secondary timing chain broke.

Removing the exhaust cam to check compression is a way to diagnose for damaged exhaust valves. Hopefully you are as lucky and have escaped with no damage and have ample compression. If not, replacing the engine with a second-hand unit is probably less expensive as long as the replacement engine has had uprated tensioners, chain guides, tensioner blades and chains installed prior to being fitted to the vehicle.

As previously suggested, further disassembly and diagnosis are required to determine the extent of damage, if any, and how to proceed with repairing the engine in situ with the RH cylinder head removed, or replacing the engine.

 

//////////////////////////////////////////////////////

Hi Bob guaff/NB cat

just spoke with the mechanic, good news is no damage to the valves/engines.The secondary chain has fallen to the bottom.so they have remove the front to retrieve them.They stated it wud be advisable to replace the chains(qty-04),guides and 4 tensioners.cost around 3000.00 i think its little to much.do i have any choices.I was told ford t/bird and lincoln LS has the same engine.can some one tell me what is equivalent model year of LS and t/bird for stype 2000.This is to save the cost, as same part with jag brand is more expensive.pls help.

 

The labor should not be more than about 10 hours TOTAL!!!!!!!!!!!!!!!

The parts are not $2000 so I think someone is overcharging, but that is just my opinion.

The 3.9 LS/Thunderbird parts are sometimes a little less expensive but complete kits can be had on the internet. A few hours shopping can save you money.

bob gauff

 

Well, that is good news indeed! I hope they performed a compression test to diagnose any possible valve damage.

If there is no damage to the exhaust valves, the timing case cover can be removed and the chains and associated parts replaced. The price of 3000$US seems a bit high for the amount of work involved.

The Lincoln LS uses a variant of the engine design (AJ30/AJ35) and displaces 3.9 litres due to internal differences. While the AJ26 and AJ30/AJ35 appear similar, I personally have no experience with attempting to substitute one for the other. Perhaps another forum member can offer advice on the possibilities of fitting the Ford version of the engine to your car.

 

I've heard of using 3.0 V6s from Fords, although various components need to be swapped, but not the V8, unfortunately.

I don't see a good way out other than rebuilding what you have.

May be time to cut your losses and move to a different car... :-(
==================================================
Jaguar: Grace, Pace, and Space - Sir William Lyons

 

I call bs only because i see no way that secondary chain can get to the bottom of the engine. It is behind the primary and if it were to have gotten down there it would not be pretty. And to answer questions on chain replacement. If a plastic secondary shoe goes in between the chain and sproket and gets chewed up always replace the secondaries. If you pulling the front timing cover(dont need to for secondaries) then it is wise to do then all. Chains, tensioners, guides.
And yes this repair at that cost exceeds the value of the car. Especially for the 2000-2002.5
And NO you cannot swap in a Ford V8, theyre differant, you can do the v6 but the time and costs if youre not doing the work again will exceed the value of the car and unless there is sentimental value(kid born in or concieved in, etc) then again you're pissing away good money

 

///////////////////////////////
Brutal,Bob,NB and the rest
thank you guys for the info.Got the car out from repair, and drove to LAX(work) no issues so far.They replaced, both primary timing chains,both secondary chains,all 4 tensioners, guides and the water pump.cost labor and parts 3191.00( arm and a leg).

 

////////////////////////////////

Brutal- quick one for you

same car-2000 stype V8. When gear is on drive hear a rattling noise from gearbox area(Like something is loose and rattling due to vibration).I also noticed while walking , FORD explorer that passed by me having the same sound,since this has a ford gearbox.Is this sound common/familiar? what is the remedy for it.

 

That's a lot of $ to invest in a 2000 MY - low mileage? (I hope) as far as the noise your hearing - hope it's an easy fix. Maybe something is loose underneath... take a peek...

On the bright side - you should never, ever have to worry about any engine tensioner issues moving forward... did they use the 4th generation tensioners? metal?

 

so back again, timing tensioner broke... The pastor ones I believe is the clickjng I'm hearing.. OK to drive?