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4.6L Explorer engine timing chain ooops!

Got a local customer with an Explorer who came to the shop with a noise coming from the front cover. As I suspected the timing chain guide on the pass side was broken completely and both movable guides were worn through, right down to the tensioner. Attached is some pics.....
 

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4.6l dohc 4V cobra timing chains

HI thanks alot for everything usatoolwharehouse had the cheepest price for the timing tools at $107 sears was like $160. I am a little confused though because you have to take off all gears and chains and all like at once do i need 2 cam holding tools to prevent the cams on the side that does not have the holding tool on them or do you put the D slot plates one for each side. If you could clear that up it would be helpfull I have the ford shop manuel for thta section and dont rember it going over that part when i read it.. And sence I am going with the arp cam and crank bolts for the gears and the factory ones are tork to yeild what is the tork spec i use for them sence the new bolts are not one time use.. Ok and what is the crank trigger wheel? never heard of one. Do i need to get a new one also. I am also going to replace the crank seal on the timing chain cover it seems i need a tool to remove that seal. The shop manuel says I need timing chain cover removel tool . Do i realy need that tool how does it work what is it like? and the shop manuel says to take off the oil pan clean it replace the oil pump pick up filter and tube my uncel also says i should replace the pump too . What do you think about that right now i live at a apartment so doing that could be a chalange considering you have to unbolt the trans and motor mounts and lift it up to do this job I want to do it but is it something that can wait a couple hundred miles on the car after i do the chains ? And do you know anything that you can do to this motor to get some more porwer and posibly better gass milage I was thinking equal langth shorty headers msd coil packs and wires I am talking cost effecient I do have 2 t3 15 pound each turbos they are off of SVO mustangs but i would have to tone them down to 8 pounds cause i dont have the money to pull the motor and put forged crank rods and pistons in it I dont know what do you think?
thanks again for all your help and great pic
 






HI thanks alot for everything usatoolwharehouse had the cheepest price for the timing tools at $107 sears was like $160. I am a little confused though because you have to take off all gears and chains and all like at once do i need 2 cam holding tools to prevent the cams on the side that does not have the holding tool on them or do you put the D slot plates one for each side. If you could clear that up it would be helpfull I have the ford shop manuel for thta section and dont rember it going over that part when i read it.. And sence I am going with the arp cam and crank bolts for the gears and the factory ones are tork to yeild what is the tork spec i use for them sence the new bolts are not one time use.. Ok and what is the crank trigger wheel? never heard of one. Do i need to get a new one also. I am also going to replace the crank seal on the timing chain cover it seems i need a tool to remove that seal. The shop manuel says I need timing chain cover removel tool . Do i realy need that tool how does it work what is it like? and the shop manuel says to take off the oil pan clean it replace the oil pump pick up filter and tube my uncel also says i should replace the pump too . What do you think about that right now i live at a apartment so doing that could be a chalange considering you have to unbolt the trans and motor mounts and lift it up to do this job I want to do it but is it something that can wait a couple hundred miles on the car after i do the chains ? And do you know anything that you can do to this motor to get some more porwer and posibly better gass milage I was thinking equal langth shorty headers msd coil packs and wires I am talking cost effecient I do have 2 t3 15 pound each turbos they are off of SVO mustangs but i would have to tone them down to 8 pounds cause i dont have the money to pull the motor and put forged crank rods and pistons in it I dont know what do you think?
thanks again for all your help and great pic
 






Lots of questions. Let me try to sort thru this for you. If you are only replacing the primary chain guides (the long chains), then there is no reason to take off the short (secondary) chain up top. This means you don't have to take off the cam gears either. And as long as the cam gears don't come off, then you don't have to replace the cam gear bolts. You certainly don't need new cam gears, unless yours are messed up, or worn badly or something. Sounds to me like you're gearing up to do a much larger job than what is necessary to fix your car.

The cam holding tool just holds the two cams relative to eachother. This would be good for when you are removing or tightening the cam bolts, etc. If you're not doing that, then you probably don't even need to use that tool. The D slot plates are for taking two completely free wheeling cams (all chain stuff off the motor), and lining them up relative to eachother. In other words, for setting up cam timing from scratch.

I think the ARP torque specs would be exactly the same as stock, but the sequence for tightening wouldn't need those tighten-loosen-tighten steps. (This is an interesting question though, and might be worth calling ARP tech support about for verification of torque spec). Definitely get the ARP crank bolt, but you shouldn't need the cam bolts, since you don't need to take the cam gears off unless they're bad.

The trigger wheel is a black wheel about 6" in diameter, that has "teeth" on it. The crank sensor (located in timing cover on the side) sees these teeth go by, and that's how the computer knows where the engine is in it's revolution, and also how many RPMs the motor is turning. They normally aren't bad, but in some race motors there have been reported problems of them cracking. Autofab makes a billet aftermarket one for maybe 80 bucks or so if you want one. Just make sure it goes on the same direction it came off, and don't forget to put it on before putting the timing cover back on.

With the cover off, the crank seal can be tapped out easily. Before you remove the old one, simply look at how deep it's installed. Flush, if I recall, with the front of the timing cover. Tap the old one out, tap the new one in, and try to get it nice and straight. The factory tool just lets you smack the new seal in without thinking, to the exact depth and straightness every time. Not a necessity if you look at how the old one is sitting in there, and just take your time to tap the new one in the same spot. I did mine that way, and it didn't leak a drop. It might even have a flange on it, to set it's depth, but I just don't remember. I also don't remember if you're supposed to use a thin layer of silicone around the seal... I don't think so.

The timing cover just unbolts. But don't forget to unbolt the 4 studs/nuts on the BOTTOM of the timing cover, coming up from the oil pan. You'll need a new timing cover gasket set and some black silicone for where the different edges of things come together. Read the factory manual for instructions on where to dab some silicone.

The oil pump is at the front of the crank, and the pickup tube runs from the pump, back to the rear of the pan. The tube and pickup assembly are one piece, if I remember right. You would need to be careful to make sure that the pickup is at the same depth later as it is now, so it doesn't get angled away from the pan. I really don't think you need to do this. They're worried that if the plastic pieces of the guides clog up the pickup, the motor would starve for oil. Chances are that with enough oil changes, these pieces won't present a problem. If you're worried about it, you could pull the pan and just clean the pickup tube right where it's at, and not have to risk screwing up putting it back on wrong or something. Most of the plastic pieces probably come out with oil changes anyway. The rest that makes it thru the pump probably get caught in the oil filter, which does a great job of filtering oil. Nothing large will ever get thru an oil filter. And I've got news for you. If you have a 96-04 modular motor car, you have to pull the K-member while supporting the engine from the top with a cross brace, in order to get the oil pan off. NOT an apartment complex type job. If you've got good oil pressure, I wouldn't worry about it. And if you do have problems there, you also have to replace (cannot clean) your factory oil cooler, which is the big round piece the oil filter bolts to. It's probably $200. So you're getting in deep, trying to do that job. Don't get into any of that oil pump stuff if you don't have oil pressure problems. Verify problems by putting an aftermarket oil pressure guage on the car and make sure the pressure doesn't dip at wide open throttle.

Back to the chains, if your only problem is the guides, then I would just put the motor at exactly TDC on the compression stroke (you can use the OTC tool kit's crank holding gear to do that, or a long screwdriver or TDC finder). Then I would take the balancer, timing cover and trigger wheel off, and then paint a mark on the cam gear and timing chain, and then again on the crank gear and timing chain. Unbolt the tensioner, unbolt the guide and replace, replace the tensioner, and pull the allen wrench, which snaps tension on the chain. Make sure nothing moved, and the paint marks still match up, and you should be good to go. Reassemble.

Notice the bottom timing cover bolts...

Engineteardown007.jpg


Oil pump pickup tube partial picture:

Mustangtemporary045.jpg


Here's a side view. Notice how my screen has junk partially clogging it? That was not enough to cause an oil pressure problem. These were actually paint chips from the oil pan. They got there when the Vortech supercharge was originally installed, due to having to literally poke a hole in the front of the factory oil pan, in order to tap it for a return oil line from the blower. What a crap deal. That's why in the picture of my Canton race oil pan above, you will notice I had a pipe thread tig welded into the front of my pan, and then a -8AN fitting screwed into that, so I could run quality race hose up to the blower instead.

Mustangtemporary055-1.jpg


Trigger wheel installed:

Mustangtemporary136.jpg


Trigger wheel closeup:

Mustangtemporary138.jpg


You should also know that you will need a harmonic balancer remover/installer tool, and a power steering pulley remover kit. You cannot do it any other way than to get the balancer and power steering pump and pulley off. Water pump can stay on. Belt tensioner can probably stay on.

There are so many things you can do to your car to get more performance out of it, it isn't even funny. Way too much to list here. But you're barking up the wrong tree so far. If your ignition parts are bad and you want to upgrade to MSD wires, fine. Use stock Motorcraft, or NGK plugs. Ford Racing or MSD wires. STOCK coils. Shorty headers are good, but rather hard to install. (Although if you do have to drop the K-member and pull the oil pan, this is THE time to add headers!). This must be done on a lift, and isn't easy. Installing turbos would be a rather huge, expensive deal. Not for the budget-conscious, trust me. If you have any hesitations or hickups at around 3000 rpm at full throttle, clean your IMRC plates. Install a cold air intake tube and K&N filter. Clean your MAF meter if you haven't before. The best gains you'll get are going to be from just getting your car running 100% factory right, and then adding exhaust upgrades and an SCT chip.

PM me if you want, since selling race parts and tuning Mustangs is what I do.
 






4.6 DOHC 4V cobra

Hi thank you again for the great info and pics.
Well i have the passanger valve cover off all the pullys , crank dampener, I just took the hole power stearing pump off instead of messing with pulling off the pully even though I have a puller
I got a kit from engine pro all new gears, chains, tensions, guids and a feel pro gaskit for the cover If i wake up early tomarrow i am going to be picking up the arp crank and cam bolts and the crank seal.
So yes I am replacing more than needs to be replaced but I said screw it while i have it apart why not replace it all.
So I am just waiting for the cam and crank tools to get hear and just have to take off the driverside valve cover and then comes off the timing chain cover. And then try to put all 8 new gears 4 chains and all that. Talk about a anixty atack once I take off the timing cover. Any other advise if there is any left would be great .
Again thanks alot you have been more than a great help
 






Hi thank you again for the great info and pics.
Well i have the passanger valve cover off all the pullys , crank dampener, I just took the hole power stearing pump off instead of messing with pulling off the pully even though I have a puller
I got a kit from engine pro all new gears, chains, tensions, guids and a feel pro gaskit for the cover If i wake up early tomarrow i am going to be picking up the arp crank and cam bolts and the crank seal.
So yes I am replacing more than needs to be replaced but I said screw it while i have it apart why not replace it all.
So I am just waiting for the cam and crank tools to get hear and just have to take off the driverside valve cover and then comes off the timing chain cover. And then try to put all 8 new gears 4 chains and all that. Talk about a anixty atack once I take off the timing cover. Any other advise if there is any left would be great .
Again thanks alot you have been more than a great help

Yeah, don't do anything more than what you have to. You're just asking for unnecessary trouble. Replace all the guides, but don't take off stuff like the gears and short chains, or you'll have to go all the way with setting the cam timing. It's just not the sort of job most amateurs will be comfortable doing.

If you do decide to do it, grab a digital camera and take pictures of every single step, and closeups of how things looked before you took it apart. Which way pieces faced (like the trigger wheel and crank gear, cam gear spacers, etc). Take lots of pictures. And make sure you have it at TDC on cylinder #1 (passenger side, front cylinder) on the compression stroke first, before you take off the chains. This will save you some headaches later, if you get into trouble.

I'm not trying to be negative about what you're doing, but you're just spending a lot more money and risking alot more trouble than what you really need to fix.
 






Is this a timing chain problem?

My car 02 V8 Ex has been making a peculiar noise from the front of the engine for about a month. I found the fan belt to be on verge of breaking, which I replaced. It also sounded like one of the belt tensioners were rattling. I never had a chance to replace it.

On the way home from work tonite, the noise was very loud, sounded like the engine tapping. The oil pressure started fluctuating, with acceleration and braking. When I pulled over to check it out, the truck stalled and wouldn't start back up. After AAA towed the car to my house, I tried starting it again, which it did, but of course with the loud tapping noise.

A couple of mechanics I know says what I described sounded like bad oil pump or oil psi switch. They said it is a good chance my engine is toast.

Is there anymore info out there on whether I need an engine, oil pump, or timing chain?
 






You need to figure out where that noise is coming from. Start it up, and listen carefully (use a stethoscope) on the front cover. Be careful of the fan. If your noise is coming from the front cover, you're probably ok. Most likely, you've broke a guide or tensioner, and the slack in the timing chain is slapping the chain against the cover or something. I've heard them broken before in a Mustang... sounded like a knocking bottom end type noise to me. Turned out to be the guide broke.

The mod motors seem to have a guide fatigue problem. At least in the Mustangs. They apparently suffer from harmonics in the engine. The stock guide nylon also wears thru over time. With a sudden noise like that, I would suspect the chain/guides/tensioner. You could probably pull the valve covers off (start with the side you suspect based on noise), and look down at the chain from the top. With a screwdriver or something long, you might be able to see if the chain still feels like it's tight. If it is, then the guide or tensioner isn't entirely broke loose. If you found slack, you found your problem.

Oil pressure would likely not be affected by a chain problem at all. So hooking up a manual oil pressure test guage down by the oil filter wouldn't hurt, if you have one.

The oil pumps on these are ran off the front of the crankshaft. They're the gerotor type. Typically, they don't fail, except occasionally in hard racing. I don't think I've really ever seen a stock one fail in a non-race application...

http://en.wikipedia.org/wiki/Gear_pump

If this is a repair over your head, I would suggest towing it to Ford or a shop, and not trying to crank it up more than once more, just for a quick sound test. Do make sure that there isn't any belt-driven accessory problems going on (broke tensioner or fan, etc) before you panic.

Even if it is a broke chain component, it's not the end of the world. If you can't find a cheap mechanic to fix it, check with your local Mustang speed shop. It's a motor they're probably plenty familiar with, and they just might be cheaper.
 






You need to figure out where that noise is coming from. Start it up, and listen carefully (use a stethoscope) on the front cover. Be careful of the fan. If your noise is coming from the front cover, you're probably ok. Most likely, you've broke a guide or tensioner, and the slack in the timing chain is slapping the chain against the cover or something. I've heard them broken before in a Mustang... sounded like a knocking bottom end type noise to me. Turned out to be the guide broke.

The mod motors seem to have a guide fatigue problem. At least in the Mustangs. They apparently suffer from harmonics in the engine. The stock guide nylon also wears thru over time. With a sudden noise like that, I would suspect the chain/guides/tensioner. You could probably pull the valve covers off (start with the side you suspect based on noise), and look down at the chain from the top. With a screwdriver or something long, you might be able to see if the chain still feels like it's tight. If it is, then the guide or tensioner isn't entirely broke loose. If you found slack, you found your problem.

Oil pressure would likely not be affected by a chain problem at all. So hooking up a manual oil pressure test guage down by the oil filter wouldn't hurt, if you have one.

The oil pumps on these are ran off the front of the crankshaft. They're the gerotor type. Typically, they don't fail, except occasionally in hard racing. I don't think I've really ever seen a stock one fail in a non-race application...

http://en.wikipedia.org/wiki/Gear_pump

If this is a repair over your head, I would suggest towing it to Ford or a shop, and not trying to crank it up more than once more, just for a quick sound test. Do make sure that there isn't any belt-driven accessory problems going on (broke tensioner or fan, etc) before you panic.

Even if it is a broke chain component, it's not the end of the world. If you can't find a cheap mechanic to fix it, check with your local Mustang speed shop. It's a motor they're probably plenty familiar with, and they just might be cheaper.
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Hey thanks a lot. I'll try that route first.
Posted via Mobile Device
 






1997 4.6L 4V DOHC COBRA motor timing chain gear's, guids, tensioners,and chain rel

1997 4.6L 4V DOHC COBRA motor timing chain gear's, guids, tensioners,and chain relpacement

Ok tdc of compression side cyl #1 . Is the only real way to know its on the compression stroke is by roting the engine and watching the cams and lifters to see when the valves are closed and to that question the 4V DOHC 4.6l the secondedary valves open at 3250 RPM's or close to that so are thoes valves even going to move when I rotate the engine by hand to see when the valves are closed for the compression stroke (and how do the secondary valves open at 3200 RPM's what makes them open I am thinking about hooking up a switch in some sence so i can controll when the secondary valves open so i can do some testing on performance and gas mileage..on the svt contour 2.5L DOHC motor I think there some linkage that is conected to the throttle body Not positive but I drove a svt contour that looked like that link was missing when driving did feal like secondary valves were opening I think its 3500 RPM's for that motor )

and what do i do about the tork specs some of the specs the camshaft sprocket bolt says 82-95 ft-lb s so is it best to do the lower torque spec like 82 the middle like 88.5 ft lbs or the high end 95 ft lbs (do not want anything to come lose) and front cover bolts, drive belt tensioner bolts ,drive belt idler pulley bolt, water pump pulley bolts , power steering pump to engine bolts, Timing Chain Tensioner Bolts,and ignition coil brackets-to-engine front cover bolts all say 15-22 ft lbs should I go low middle or high with whose torque specs ?

and then E for pully to crankshaft bolt says tighten to 66 ft lbs. 2. loosen one full turn. 3. tighten to 36 ft lbs . 4. tighten an additional 90 degrees. But I got the arp crank pully bolt so what do i do for that torque spec??????

and then oil pan to engine front cover bolts says k witch says 1. tighten to 15 ft lbs then 2. tighten an additonal 60 degrees . So what do i do for them and does that mean i need to get new bolts for that and what spec would i use , or can i use the orignal ones ?

O ya and are the camshaft cap bolts also 1 time use bolts cause it says tighten to 71-106 in lbs then loosen 2 turns then tighten to 71-106 in lbs ? and would it be best to go low 71 in , middle 88.5 in lbs or high 106 in lbs because first thing i did before i realized what i really need to replace was I took the valve cover off took one cam cap bolt out cleaned it put a little lock tight on it and put it back in and torqued to 8 ft lbs i did that for every cam cap bolt on passanger side in the order the shop manuel says . I hope i do not have to go get plastagauge and mesure the oil clearence . Sence I am working on this at a apartment out in the open the less time I have the engine exposed to the air the better . ?

I know this is alot any help with the things I asked would be great and really helpfull I am perticular in doing things the right way the first time (just not spelling words) any mistake with this motor could be really expensive I just want to get it back on the road and have it be reliable.

thanks again
 






4.6l DOHC 4V Cobra motor timing chain?

4.6l DOHC 4V Cobra motor timing chain?

Well I finaly got the front cover off and to my surprize all of the guids look bairly worn. On the passanger side primairy chain the tensioner seemed to be weak I was able to push it in with not much pressure from my hand so I am going to guess that, that tensioner is wore out.???

On the driverside primary tensioner I was not able to move it at all with my hand. Does that sound normal? About how much pressure do the tensioners put out?? Or does that sound like that one is stuck (sezed) ??

I am replacing everything but my bigest consern is that on the passanger primary and passanger secondary chains the rivets that holds the chain togather are ground down a little bit (this is on the side of the chain that faces tords the headlights on both chains) but I can not find what they were rubbing on the only thing that looks like the primary chain could have rubbed on is the crank gear sensor (i forget what that was called) but there are no marks on it and no marks on the front cover???

Now when I first got the car I had a engine builder and a Tec listen to my engine both thought it was a lifter nock coming from the passanger side valve cover (the egr tube I think that is what it is called that bolts into the (header) on the passanger side was loose you could hear the leak it was pretty bad ??
Now the person I got the car from was a hack and did not know **** about takeing care of a car it had a fram oil filter on it (I think that says alot ) so it would not suprize me that they only put 5 qts of oil in it all data says this engine takes 6 qts the dipstick tube was not even there

I was told that the lifters use the oil from the engine oil to work? So now that I see that the guids are all good (even though the passanger side tensioner seems week) I am going back to the orginal dignoses I got (lifter nock ) so i am thinking it could be a lifter nock from the lifter not geting enough oil or could be cloged?? or my other thought is that maby the valve springs (or that one atleast) are wore out week what do you think????

And about how long of a break in time miles do i need to give the new chains and all that??

Thanks again alot
 






There should not be any slack in the chains. They are very tight, when you check them with your hand. You've got 4 chains. Just look at how tight the other 3 are, to give you an idea if the 4th one is not as tight. If it's not, then replace that tensioner. Check the guides carefully. There should be the aluminum guide, with a nylon strip attached to it, that actually makes contact with the chain.

Cobra motors all take 6 quarts of oil, maybe even 6.5. But running one a quart low is probably not a death nail, as long as you aren't stringing it 7,000 rpm all the time like that.

The lifters in the 4V motors aren't much like traditional lifters, and as such, wouldn't likely make the same noise as a 350 chevy when a lifter goes bad. It's overhead cam, so you've got a hole drilled in the head, where a lifter sits STATIONARY. On the other side of the rocker, you've got a valve and spring. The rocker sits on top of the two, and the cam sits on top of the rocker. The lifter is hydraulic, and has quite a bit of spring to it. So once you put the valve and spring in, lifter in, and cam in, the only way to get the rocker in is to depress that lifter down, put the rocker in, and let the lifter pop back up, pinching the rocker in place. In order for that lifter to make any noise, you would have to have the spring inside the lifter be broke or worn out, and cause the rocker arm to be loose under the camshaft. That would probably throw a rocker off if that happened. Easy enough to check, pop the valve covers off, look for missing rockers. Then, if ok, turn the motor over by hand so that you get each rocker up at the valve-closed position. Then, push on the rocker arms and see if any are loose at all. They should all be very tight, as the lifters (hydraulic lash adjusters actually) should have enough spring in them to keep the rocker pushed up tight against the bottom of the camshaft.

Back to the tensioners, on the 96-98 4V, there is a little plastic ratchet inside the tensioner... looks sort of like a jack stand type of arrangement. As the chain wears, the ratchet pops further out, and the teeth on the ratchet stop it from going back in. This way the loose chain doesn't have to have the oil-fed tensioner take up all the slack every time. Just the slack between the top of the ratchet position and fully tight chain.

You need to replace the tensioner, and get to the bottom of the chain problems. Replace the chains if you feel they're a problem. But do try to figure out what is rubbing on their rivets. I can't imagine what that might have been offhand.

Back to the lifters, you might get valvetrain clatter, or a thrown rocker arm. But you will not get lifter knock with a 4V, because the lifters do not move. At most, you get a tick from the rocker not being held tight enough against the bottom of the cam. By the way, the rocker arm has a roller on it, that rides against the cam, so it's really a roller rocker.

Chances are, due to centrifugal force, the chains (if loose) would only stretch outward towards the tensioners and guides. Not really move forward and backward so much. But all the same, once the front cover is off, the crank sensor reluctor wheel just slides off. Take a look at it and see if that's your rivet wear problem.

New chains and tensioners don't really have a break in time. They should work from the get-go. But if it makes you feel better, drive it easy for 100 miles, then change the oil, and you're good to go.

When installing the tensioners, there is a hole in it, where you compress the tensioner, put a small tool or allen wrench in the hole, and install the tensioner and chain. When you're ready to have tension, you just remove the tool and the chain snaps tight. Watch your fingers.

On the 96-98, there is no special tool. But on the newer 4V motors, I think there is an actual tool made for doing that. In either case, an allen wrench should work. Ideal tool would be a straight, round piece of metal, curled on one end big enough to put your index finger in.
 






4.6L DOHC 4 valve 1997 cobra motor

Hi thanks for all the good info

I took off the crank sensor wheel and there is not a single mark on it?? So I do not think it is that I looked but guess I will have to keep looking around for what they were rubbing on.

I will rotate the engine as soon as I have a chance and check out the roller rockers and all that.

So if there in ANY play between the rockers and lifters/ springs that is not good???

And if all the lifters are there but there is play in the rockers would that be the valve springs????
 






4.6 4v cobra motor timing chains

One more thing that I found odd is that the gears timing marks line up where they are sopse to but the marks on the chains are like 6-8 in away from where they are spose to be (this is one the chains and gears that were (are) on the car when I got it)
Does this tell you anything???
 






The lifters have a strong spring in them, plus oil. The oil is designed to escape the lifter at a predetermined thickness. This is why you REALLY should run motorcraft 5w20 oil, or at the most 5w30. Plus, motorcraft oil is semi-synthetic.

If there is any play between the hyraulic lash adjuster and the rocker arm, with that rocker/valve at the zero-open point, then something is wrong. You probably won't find that issue though... if there was any play, the motor would have already thrown the rocker arm off.

Valve springs, you just need to inspect. They're down in a hole, so it's hard to do. But with an inspection mirror and light, you should be able to see them pretty well. Look for pieces of broken valve spring in the oil, the bottom of the rocker area in the head (gravity and oil flow would bring it there), or wedged in and around the rest of the valve spring. I doubt you'll find anything here either, unless you've over-revved the motor bigtime.

The gears don't line up with the chain, because the chain is longer than the diameter of the gears. In other words, those gears rotate many more times than the chain does. But if you were to rotate the motor over enough times, eventually, you would get back to where the chains and gears do line up. The chain has one different colored link on it, to denote the top of the cam gears, and possibly another one at the bottom for the crank gear, but I don't remember for sure on that one.

This is why we paint the chain, instead of trying to line it back up. If the chains come off, or get replace, you would use the colored link on the new chain. And I would probably paint the crank gear end of the new chain, and dab the colored link as well, just to have sharp, fresh, easily visible marks on the chain. You simply fold the chain in half, with the colored link on top, and whatever link is on bottom would be the one to paint, and use for the crank gear.
 






This is a great thread guys! Thanks for all the information.

My '03 Eddie Bauer has what sounds like a rod knock from the rear of the motor but I suspect it's these timing components. At 145,000 miles I think it would be good to replace them anyway. We really like the truck and plant to keep it 2-3 more years.

Would it be easier to pull the entire motor to do this job and do the work on a motor stand?

Edit - mine is the 4.6L V8
 






This is a great thread guys! Thanks for all the information.

My '03 Eddie Bauer has what sounds like a rod knock from the rear of the motor but I suspect it's these timing components. At 145,000 miles I think it would be good to replace them anyway. We really like the truck and plant to keep it 2-3 more years.

Would it be easier to pull the entire motor to do this job and do the work on a motor stand?

The SOHC V6 motors have a unique timing chain setup. Basically, there is one chain to the head in the drivers front, and one in the passenger rear. That one is connected by a jackshaft that runs thru the middle of the motor. The OHV V6 and all V8 motors have timing components only in the front. So if you have a noise and it's a sohc v6 car with high mileage, then yeah the only way to do that is to pull the motor. (It COULD POSSIBLY be done pulling the trans and letting the motor dangle down some, but I have not heard of anyone trying that). Putting in a used motor often becomes more cost effective, unless you have the time and patience to do the work yourself.

If you have any other motor than that, you might have a real noise somewhere in the motor. But before condemning the rods, make sure you don't have any broken flywheel or converter bolts, or a cracked flywheel. You would pretty much have to pull the trans to figure that out for sure. Unless you see the cracked flywheel thru an inspection cover or something.

There are other threads on here that talk in depth about doing that SOHC V6 job.
 






1997 4.6l 4 V DOHC cobra svt motor

4.6 L dohc 4V cobra motor. Ok after finishing the tiniming chains and gears witch was so easy with useing the OTC timing tools was about to put the valve covers on and noticed something (like I have said before I got this car from some one who got it from a auction and I honestly do not want to know how drunk the person was who worked on this car ) but the holes in the heads closes to the oil pan below the bottom cam what are they for cause I found about a 8 in long bolt in the hole closes to the fire wall I am guessing there is not sopse to anything in that hole?????
 



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Engineteardown011.jpg


If you look at this head, you can see two rows of head bolts. The top row is even with the 4 spark plug holes. The bottom row is just below the exhaust (lower) cam. Just below that, there are 3 holes visible in the picture, in the very bottom of the head. Those are oil return holes. There should not be anything in them! If you found an 8" bolt in one, I would suspect that the cylinder head might have been off, or at least that a head bolt was removed and just left in there as a convenient place to put it while the guy worked. Check every one of your head bolts to make sure they're all accounted for.

Note: Mine has ARP head studs, so in the pics you are seeing a stud and a nut, where normally you would just see a head bolt. Also, (if memory serves correct), the stock head bolts might be torque-to-yield and not reusable. If you do find that you're missing a head bolt in the motor somewhere, I would check that area real closely for signs of a blown head gasket.
 






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