Timing crankshaft to countershaft

They don't tighten. They wear out and need replacement. They are not very expensive.

The tensioner is located at the rear (right side) of motor. Jack the car up, remove right front wheel, remove the splash guard. Looking up, above the exhaust manifold near rear of motor you'll see a BLACK 25mm or 27mm bolt head....That's the tensioner.

The 4.0l sohc v6 is notorious for breaking the plastic chain guides. You will need t remove the engine to repair it properly and there are lots of special tools required to properly time the vehicle. There are actually 4 timing chains and I suggest replacing all 4 and their respective guides and tensioners.

timing chain noise? is the timing chain hitting the cover? or is the chain worn out and not meshing with gears?

Pull your Serpentine belt, remove the Cam Belt Cover, (it may be advantageous to remove front wheel in the Cam Belt side) Remove the timing belt and time the engine to specifications, make sure you are on #1TDC, remove the tensioner and replace. if there is and Idler pulley replace that as well. You can use Spray Carb Cleaner to clean the pulleys before replacing the belt. Note, you may have to also remove the Harmonic Balancer and pulleys from the crankshaft.

Look for some Youtube videos on this repair. If I remember correctly the links on this chain have different color metal for the spots that the cam tooth goes against. When each side is in the proper tooth the right and left colored links will be on the cam mark and the crank mark should be on the timing TDC mark. Sounds like the slack you describe is wrong and a tooth is off because the tensioner is allowing slack.. You need to slip a tooth one way or the other until the tensioner has room to be in a neutral position.

Get Ford timing tool kit, part = otc-6488 (For about $119 USD on eBay)

4 timing chains (3 front including the optional balance shaft chain + 1 back)

2 cam guides (1 front + 1 back)

2 oil tensioners (1 front + 1 back)

1 jackshaft tensioner (1 front)

1 jackshaft guide/cassette (1 front)

1 balance shaft tensioner (1 front) (will probably be ok, so dont replace it)

1 balance shaft guide (1 front) (will probably be ok, so dont replace it)

new sprockets + bolts + gaskets etc.

new spark plugs + throttle body cleaner + lithium grease spray + oil change

head gaskets

some of these parts (the front stuff) can be obtained as a primary timing chain rattle noise kit Part# = 2u3e-6d256-** ab for 4*4 & bb for 2*4.

The kits also have later part numbers for us$ 76 @ http://www.fordpartsonline.com

My parts order (without the balance shaft stuff) was:

$76.04 KIT-TENSIONER TIMING 2u3e-6d256-ab

$47.93 Engine, Camshaft and timing, Timing chain, TIMING CHAIN, Explorer, Mountaineer, Rear - 4.0L SOHC - 4.0L SOHC

$57.36 Engine, Camshaft and timing, Chain guide, CHAIN GUIDE, Explorer, Mountaineer, Jackshaft To Cam - 4.0L SOHC - 4.0L SOHC

$103.22 Engine, Overhaul gasket set, OVERHAUL GASKET SET, Explorer, Mountaineer, Upper (Valve Grind) - 4.0L SOHC - 4.0L SOHC

$28.93 Engine, Camshaft and timing, Tensioner, TENSIONER, Explorer, Mountaineer, Upper - 4.0L SOHC - 4.0L SOHC

Its worth mentioning that this procedure is not enjoyable at all and should be undertaken with at least 8 full days to completion (I recon you could do it in half the time the second time).

It is basically on entire engine re-build with both heads off and the engine out of the vehicle.

It is not possible to do the rear chain or sprocket with the engine in the car as the flywheel needs to come off + at least 1 head, but it is possible to do the front primary chain and or front cam chain with the engine in the car.

You will be a ford exploder and timing expert after you do this - the main reason should be the love of your American built vehicle. Its a solid car - except for the plastic guides!

Disclaimer Note: This is how i successfully did the job, but i am not a ford mechanic and don't hold me responsible if this does not work for you.
Timing Overview

A Small Sprocket on the crank turns a larger (2 to 1 ratio) jackshaft sprocket that is in turn connected front & back to the 2 camshafts.

Thus a 360o turn of the crank will turn both the camshafts 180o.

Firing order is 1-4 2-5 3-6, Right side numbers 1,2,3. Left Side = 4,5,6.

At TDC pistons 1 & 5 are fully raised, thus 1 is about to spark & 5 is evacuated.

The engine will turn freely (no piston to valve contact) with the cams 180o out, it will even run (roughly) with 1 out 180o, any other settings may cause major damage to the valves.

The 2 cam shafts come with timing markings, "yes" real timing marks that anyone can use (even without special tools) to ensure correct timing.

The way to time it is to ensure both the off centre cam shaft slits are level/flat with the head.

With the engine at TDC both the cams need to have the off centre slot in the same position either up and level or down and level.

It is super critical that both the camshafts are 100% in sink with each other, i.e. not a few degrees off, the engine computer can compensate for crank timing but not engineering failure.

Be warned the camshafts can turn easily fast & hard by themselves as a few springs are compressed at TDC, I got my finger jammed and its still healing + if the engine is not at TDC you may damage a valve.

Now heres the hard thing that you will need special tools for - if you need to change the timing, you will need to be able to undo the cam sprocket bolt on both cams & these are done up real tight.

There is a tool that you attach that has 2 pencil thick shafts that fit into the sprocket and prevent it from turning - then you need to put about 90Nm of force on the bolt (remember the rear one if LHT)

For the $money$, its well worth getting yourself the tool kit - it will save you hours in the long run. Search eBay for otc-6488 should be US $119 - then sell them again for say $100.

There is also a tool version of the oil tensioner in the kit that screws right in and puts the correct amount of force on the chain + guide, to enable you to do up the cam bolt with the chain and sprocket in the right spot on the cam.

A change of oil may help, but problem likely due to a combination of stretched timing chain and worn anti rattle chain tensioner.
If noise persists, a new chain and checks to tensioner would be worthwhile.

not true. SOHC 4.0 tensioner and rails fall apart, allowing the chain to slap and do damage, or even break. book it. in order to replace rioght side cam chain and tensioner, the engine MUST BE REMOVED! if it has balance shaft chain in oil pan, there are a total of four chains in this engine.

ok, the timing covers have to come off, which means taking off accessory drive belt, possibly alt. ps pump, ac,etc. timing covers need to come off along with the crankshaft pulley. if it is a DOHC there will be 2 gears on the top, with a tensioner and a pulley for the waterpump, the crank shaft will have a toothed gear also. the gears need to be aligned properly or engine damage will ensue if it is a interference engine. 6 to 10 bolts for the waterpump, gaskter etc. your best bet is to buy a hanyes manual at a local parts store for around 20 bucks. it is a complicated repair if you dont know what your doing. if i knew what year the engine is and if it is SOHC or DOHC and if it has a chain or belt i could help you more.. good luck