Do you have to remove the engine on a 2002 Jaguar X-type 3.0 to adequately test, inspect and replace the timing chains and tensioners? What is involved?

top and bottom will be tight but you need to check the chain guides and the chain tensioner. To properly inspect you may have to remove an inspection hole in the cover or remove the timing cover altogether

Failure to change your oil every 4,000 at most,
takes out VVT Actuators

When you do the guides you do the tensioners
Again no oil flow & gunked up

You can see the VVT on scan tool parameters & also
should mess with fuel trim data

If you change the upstream O2 Sensors at 100,000,
spark plugs every 3 years & clean the MAF you at least
have a clean start, with the exception of the cam & chain issues

Did you take pictures while removing the originals? It's always a good habit. Below are the instructions you need to follow. Your own pics are very helpful when doing a big job like this.

1. Disconnect negative battery (1) cable.
2. Drain cooling system.
3. Remove upper intake manifold.
4. Remove cylinder head covers, crankshaft vibration damper, and timing chain cover.

CAUTION: When aligning timing marks, always rotate engine by turning the crankshaft. Failure to do so will result in valve and/or piston damage.

1. Align crankshaft sprocket timing mark to mark on oil pump housing (2). The mark on oil pump housing is 600 ATDC of #1 cylinder.

CAUTION: When the timing chain is removed and the cylinder heads are still installed, DO NOT rotate the camshafts or crankshaft without first locating the proper crankshaft position. Failure to do so will result in valve and/or piston damage.

1. Remove primary timing chain tensioner retainer cap (2) and tensioner (1) from right cylinder head.

1. Disconnect and remove camshaft position sensor (4) from left cylinder head.
2. Remove timing chain guide access plugs (3) from cylinder heads.

NOTE: When camshaft sprocket bolts are removed, the camshafts will rotate in a clockwise direction.

1. Starting with the right camshaft sprocket, remove the sprocket attaching bolts. Remove camshaft damper (1) (if equipped) and sprocket.
2. Remove left side camshaft sprocket attaching bolts and remove sprocket.
3. Remove lower chain guide (7) and tensioner arm (8).
4. Remove the primary timing chain (5).
5. Remove crankshaft sprocket (6).

INSTALLATION

1. Inspect all sprockets (4,9,11) and chain guides (2,5,10). Replace if worn.
2. For crankshaft sprocket installation procedures Refer to CRANKSHAFT SPROCKET.
3. If removed, install right and left side short chain guides (11). Tighten attaching bolts to 28 Nm (250 inch lbs.) .
4. Align crankshaft sprocket timing mark to the mark on oil pump housing (3).

NOTE: Lubricate timing chain and guides with engine oil before installation.

1. Place left side primary chain sprocket onto the chain so that the timing mark is located in-between the two (plated) timing links (1).

1. Lower the primary chain with left side sprocket through the left cylinder head opening.

NOTE: The camshaft sprockets can be allowed to float on the camshaft hub during installation.

1. Loosely position left side camshaft sprocket over camshaft hub.
2. Align timing (plated) link to the crankshaft sprocket timing mark (3).
3. Position primary chain onto water pump drive sprocket (10).
4. Align right camshaft sprocket timing mark to the timing (plated) link on the timing chain (8) and loosely position over camshaft hub.
5. Verify that all chain timing (plated) links are properly aligned to the timing marks on all sprockets.
6. Install left side lower chain guide (2) and tensioner arm (5). Tighten attaching bolts to 28 Nm (250 inch lbs.) .

NOTE: Inspect O-ring on chain guide access plugs before installing. Replace O-ring as necessary.

1. Install chain guide access plugs to cylinder heads. Tighten plugs to 20 Nm (15 ft. lbs.) .

NOTE: To reset the primary timing chain tensioner, engine oil will first need to be purged from the tensioner.

1. Purge oil from timing chain tensioner using the following procedure:

1. Place the check ball (2) end of tensioner into the shallow end of Special Tool 8186 (3).
2. Using hand pressure, slowly depress tensioner until oil is purged from tensioner.

1. Reset timing chain tensioner using the following procedure:

1. Position cylinder plunger (4) into the deeper end of Special Tool 8186 (3).
2. Apply a downward force until tensioner is reset.

NOTE: If oil was not first purged from the tensioner, use slight finger pressure to assist the center arm pin of Special Tool 8186 to unseat the tensioner's check ball.

CAUTION: Ensure the tensioner is properly reset. The tensioner body (4) must bottom against the top edge of Special Tool 8186 (3). Failure to properly perform the resetting procedure may cause tensioner jamming.

NOTE: Inspect the tensioner O-ring (2) for nicks or cuts and make sure the snap ring (1) is correctly installed, replace as necessary.

1. Install the reset chain tensioner (1) into the right cylinder head.
2. Position tensioner retaining plate (2) and tighten bolts (1) to 12 Nm (105 inch lbs.) .

1. Starting at the right cylinder bank, first position the camshaft damper (1) (if equipped) on camshaft hub, then insert a 3/8 square drive extension with a breaker bar into intake camshaft drive hub. Rotate camshaft until the camshaft hub aligns to the camshaft sprocket and damper attaching holes. Install the sprocket attaching bolts and tighten to 28 Nm (250 inch lbs.) .
2. Turn the left side camshaft by inserting a 3/8 square drive extension with a breaker bar into intake camshaft drive hub and rotate camshaft until the sprocket attaching bolts can be installed. Tighten sprocket bolts to 28 Nm (250 inch lbs.).
3. Rotate engine slightly clockwise to remove timing chain slack, if necessary.

1. Activate the timing chain tensioner by using a flat bladed pry tool to gently pry tensioner arm towards the tensioner slightly. Then release the tensioner arm. Verify the tensioner is activated (extends).

1. Install camshaft position sensor (2) and connect electrical connector.
2. Install the timing chain cover, crankshaft vibration damper, and cylinder head covers.
3. Install upper intake manifold.

NOTE: After installation of a reset tensioner, engine noise will occur after initial start-up. This noise will normally disappear within 5-10 seconds.

1. Fill cooling system.

The engine has a timing chain which is continureously lubricated by oil. When problem occours, as it requires most of everything on front of engine to be removed to replace it!

____________________
vvdi vag

Timing Chain and Gears REMOVAL & INSTALLATION 1.9L Engine NOTE: The following procedure requires the use of the puller tool No. J-25031 or equivalent, and timing sprocket installation tool No. J-26587 or equivalent.

1. Remove the timing (front) cover from the engine.
2. Lock the shoe on the automatic adjuster in fully retracted position by depressing the adjuster lock lever. NOTE: To remove the timing chain, it may be necessary to remove the camshaft sprocket. Before removing the timing chain, be sure to align the timing marks.
   
3. Remove timing chain from crankshaft sprocket.
4. Check the timing sprockets for wear or damage. If crankshaft sprocket must be replaced, remove the sprocket and the pinion gear from crankshaft using the puller tool No. J-25031 or equivalent.
5. Check timing chain for wear or damage; replace as necessary. Measure distance "L'' (40 links) with the chain stretched with a pull of approximately 22 lbs. (98N). Standard "L'' value is 15 in. (381mm); replace chain if "L'' is greater than 15.16 in. (385mm).
6. Remove the automatic chain adjuster-to-engine bolt and the adjuster.
7. To check the operation of the automatic chain adjuster, push the shoe inwards, if it becomes locked, the adjuster is working properly. The adjuster assembly must be replaced if rack teeth are found to be worn excessively.
8. To remove the chain tensioner, remove the "E'' clip and the tensioner. Check the tensioner for wear or damage; if necessary, replace it. Fig. 1: Timing chain guide and tensioner - 1.9L engine
   
   
9. Inspect the tensioner pin for wear or damage. If replacement is necessary, remove the pin from the cylinder block using a pair of locking pliers. Lubricate the NEW pin tensioner with clean engine oil. Start the pin into block, then place the tensioner over the appropriate pin. Position the E-clip onto the pin, then (using a hammer) tap it into the block until clip just clears tensioner. Check the tensioner and adjuster for freedom of rotation on the pins.
10. Inspect the guide for wear or damage and plugged lower oil jet. If replacement or cleaning is necessary, remove the guide bolts, the guide and the oil jet. Install a new guide and upper attaching bolt. Install the lower oil jet and bolt, so that the oil port is pointed toward crankshaft. To install: Fig. 2: Timing chain alignment and installation - 1.9L engine
    Fig. 3: Inspecting the timing chain for wear
    
    
11. Install the timing sprocket and the pinion gear (groove-side toward the front cover). Align the key groove with crankshaft key, then drive it into position using installation tool No. J-26587 or equivalent.
12. Turn the crankshaft so that key is turned toward the cylinder head-side (No. 1 and No. 4 pistons at TDC).
13. Install the timing chain, align the timing chain mark plate with the mark on the crankshaft timing sprocket. The side of the chain with the mark plate is on the front-side and the side of chain with the most links between mark plates is on the chain guide-side. Keep the timing chain engaged with the camshaft timing sprocket until the camshaft timing sprocket is installed on the camshaft.
14. Install the camshaft timing sprocket so that it's marked-side faces forward and it's triangular mark aligns with the chain mark plate.
15. Install the automatic chain adjuster.
16. Release the lock by depressing the shoe on adjuster by hand, and check to make certain the chain is properly tensioned when the lock is released.
17. Install the timing cover assembly.

there is no belt, it a timing chain so no need to replace.

Hello there
here is the maintenance schedule in detail
Group 4:2002 and newer X-Type, 2000 and newer S-Type, 2003 and newer XK8 and XJ8 Annually or every 7,500 miles

1. Change engine oil and filter with Mobil 1 0-40 or extended performance 5-30
2. Check and top all other fluids
3. Visually inspect undercarriage for problems
4. Inspect tires and rotate every second small service
5. Check wiper blades, replace if streaky
6. Check windshield washers
7. Check lights
8. Check belts and hoses
9. Check operation of air conditioner and heater
10. Road test car and note any problems

Every 15,000 miles this work is added:

1. Replace wiper blades and clean washer nozzles
2. Use Autologic to check for stored faults in the various computer systems
3. Check handbrake operation
4. Lubricate door locks

Every 30,000 miles this work is added:

1. Inspect exhaust system and service as needed
2. Replace air filter
3. Replace cabin filter
4. Inspect battery and replace if 4 years old or if it fails load test
5. Check serpentine belt condition - replace if cracked. Check tensioners and rollers.
6. Inspect brake discs/rotors
7. Inspect brake fluid level, brake hoses, and brake pads
8. Inspect cooling system
9. Inspect door hinges & locks
10. Inspect engine
11. Inspect engine mounts
12. Inspect exhaust system
13. Inspect fuel system
14. Inspect handbrake
15. Inspect headlights, check aiming
16. Inspect lights & controls
17. Inspect seat belts
18. Inspect steering system
19. Check wheel alignment (front)
20. Inspect wheel lug nuts
21. Lubricate accelerator linkage
22. Lubricate brake pedal
23. Lubricate weatherstripping
24. Torque propeller shaft bolts

Every 3 years this work is added, regardless of mileage traveled

1. Change brake fluid, preferably in spring
2. Change engine coolant, preferably in fall

Every 60,000 miles

1. Change transmission fluid

Every 90,000 miles

1. Replace spark plugs
2. Change final drive lubricant

These are chain driven. The only issue I have seen with these are the chain tensioners breaking. Generaly with chain driven engines, the chain will last the life of the vehicle, unless something like the tensioner or guide brakes. If it does break repairs can be fairly expensive.

The jaguar v8 has 4 timing chains located on the front of the engine behind the aluminum timing cover.
You can inspect them by remove the valve covers but to replace them you need special factory tools to set the vehicle up on TDC.
The secondary timing chain tensioners are a common failure on this vehicle which will cause the chain to break.
You can replace the tensioners to prevent this failure just by removing the valve covers and exhaust sprocket, but if this is not the issue the chains should be lifetime, not like a timing belt which is required to be replaced by time and mileage.
JPTCAT