4.6 timing chain question

[Joe in NY]

No. None are mine. My explorer only has 79K. I have some time before timing chain work.

The first pic is from a thread on here though. I googled: "Ford 4.6 timing chain" and many pics like these popped up showing many different types of guides.

 

[JakePSD]

Gotcha. Well I found out with more searching that an 02 Lincoln Continental has different ones too so I have those on their way also. This is a pain in the ass. But at least the community as a whole should benefit from this and when it comes time for you to do yours you'll know what parts to buy.

 

[drdoom]

 

[JakePSD]

More research has revealed some more interesting things. All of the previously mentioned vehicles I've searched use the same cam sprockets, including the primary sprocket on the DOHC engines (secondary is different obviously). It is Cloyes part number S764T (left) and S766T (right). The crank sprockets are the same (Cloyes part# S869) for all of the searched vehicles also except the 96 Vic (Cloyes part# S843). However it looks pretty much the same. I also found that every one of these vehicles uses the same exact chain across the board (including DOHC primary), Cloyes part# C387. It's starting to seem like you can just pick whichever the hell one you want and it will work. Unless there is a slight variance in the exact location of the cams between the SOHC and DOHC, I see no reason why a person couldn't use any of them without an issue. Now I guess the question is, if one were to draw a line at 45 degrees from vertical on the centerline of the crank on both sides, would that line intersect on the exact same place on the cams on the SOHC as the cams with the primary sprocket on the DOHC? If the answer is yes, the only question remaining that I can think of would be if there is any difference on the inside of the timing cover that would interfere with using the different parts. Looking at pictures it appears that the dimensions of everything on the engine are exactly the same, except rather than the cylinder head following the angle of the deck on the SOHC, the DOHC just angles up to make room for the additional cam, but everything else seems to be in the same location.

 

[Number4]

I'm pretty sure the 4.6 (even the DOHC) are all the same as far as the primary chain setup. Why there are so many variations in the guides? That's a great question. Could simply have to do with where the engine was made/assembled. Obviously, the 'all plastic' versions are lighter and cheaper.

One thing you could do, is compare torque and horsepower on the different engine models. It's possible that these factors play into which guides were used.

 

[welsh]

I had the same problem. Those engines are prone to problems. The engine has to be pulled to get to the rear chain. One the engine is out you can see if any of the valves are damaged (also common) I replaced mine with an '06 Duratech which has better reliability

 

[JakePSD]

I had the same problem. Those engines are prone to problems. The engine has to be pulled to get to the rear chain. One the engine is out you can see if any of the valves are damaged (also common) I replaced mine with an '06 Duratech which has better reliability

You are thinking of the 4.0L SOHC V6.

 

[JakePSD]

I have all but one of the parts now. The one side for the Continental won't be here til Tuesday. I'll start comparing stuff tonight and keep everyone updated.

 

[JakePSD]

I think changing my user name to JakePTSD might be appropriate after this. I finally got time to do some comparing. As bad as I wanted to used the nice cast aluminum guides from the DOHC engines, they unfortunately will not work. The bolt holes do not line up right. I won't bore everyone with the exact details, but unless you want to drill new holes in the guides, they will not work. It seems the DOHC head castings aren't just modified SOHC castings, they are quite different in some aspects.

So that leaves us with the SOHC guides. There seems to only be 2 options for those from my research, and that is the craptastic plastic ones that are flimsy as hell and I'm surprised any of them lasted through the warranty period, and the stamped steel guides from earlier model engines. The thing I don't like about the metal ones is how the plastic chain ride area slides up and down on the metal backing plate, however that shouldn't be a problem since the chain only goes one direction. The mounting holes are different, however the holes are already cast into the block and heads and are already threaded as well. You will have to buy a few extra bolts to use all the mounting holes though. The plastic guides use 2 bolts and the metal ones use 3, but that shouldn't be a problem. If you wanted you could probably just use 2 bolts per guide since that's all the plastic ones had, however since the holes are there, there really isn't really any good reason to not buy a few extra bolts and put them in, if nothing else for piece of mind.

On to the tensioner arms. DOHC parts also will not work. Stick with the SOHC parts. The DOHC uses a larger diameter pivot pin which makes the arm really sloppy on the SOHC pin. One could change that out if they wanted but the whole idea of this was to be a simple, cost effective upgrade to the crap plastic guides that came stock.

So overall, unless there is a large failure rate among timing guides on older 4.6 engines that I'm not aware of, I will be buying the metal backed guides, along with the metal tensioners, for my Mountaineer engine.

 

[JakePSD]

I have a few questions left for you guys. I know I asked before about just replacing guides and tensioners and NOT replacing the chains or sprockets, and Number 4 said I'd be fine, but I'd like some input from more than one person (no disrespect to your answer Number 4, just like to be sure). The engine ran perfectly fine before I pulled it, verified by myself. Also, I found after I pulled the timing cover that there is very little wear on the timing components and nothing is damaged or broken. Will I be fine doing that? Also, I read somewhere about advancing the cams a bit to improve low end torque and fuel mileage. Something on the lines of just advancing them as far as they will go in the keyway, since there is apparently a decent bit of slop there. Is this recommended? Seems like a good idea to me, its a daily driver, not a race truck, so any fuel mileage increase and better driveability from better low end power would both be a plus. If I do this, are the bolts torque to yield?

 

[Number4]

For some, the chain eats through the guides and into the aluminum backing. Had mine done this, I'd have replaced the chains and sprockets.

 

[rocco123]

Everything I've read on forums say yes they are torque to yield. Was wondering how you held your camshaft. When I was doing mine I did make an attempt to rent or borrow the tool that goes into the slot in rear of shaft but could not locate the tool. I just held it with a pipe wrench and had no problems.

 

[JakePSD]

For some, the chain eats through the guides and into the aluminum backing. Had mine done this, I'd have replaced the chains and sprockets.

So on yours you just replaced the guides and tensioners and thats it? And no issues since? What about advancing the cams in the keyway?

Everything I've read on forums say yes they are torque to yield. Was wondering how you held your camshaft. When I was doing mine I did make an attempt to rent or borrow the tool that goes into the slot in rear of shaft but could not locate the tool. I just held it with a pipe wrench and had no problems.

I've seen in a few places that the 4.6 crank bolt is TTY, but haven't seen anything about the cam bolts. Stupid either way since both have keyways. It almost makes a bit more sense on the 4.0 cam and jackshaft since there is no keyway and the sprockets are held in place by nothing more than friction.

I think I actually have the tool. When I did the chains on my 4.0 I bought a Ford master set since it was only about $130 on ebay, cheaper than most pay for just the 4.0 set. I'll have to look.

 

[boominXplorer]

I need to post the pictures of the timing chain job I just did on an 04 mustang gt with 65k ORIGINAL miles. The right chain had broke a hole in the cover. The oil condition was horrible and there was a decent amount of sludge. The car has only been used for short distance driving with cheap oil for a long time and the damage was astonishing for 65k miles. After I saw this I realized it's all about the quality of the oil in the engine. High amounts of carbon and unburnt fuel in the oil made the guides very brittle. Most chain guides I do are in vehicles with 150-200k miles. I have done a few with around 100k miles but you could always tell they haven't been taken care of.

 

[JakePSD]

So any input as far as advancing the cams as far as possible in the keyways? My parts will be here today or tomorrow so I'll probably be doing it this weekend.

 

[JakePSD]

Well I got my parts in the mail and started digging in tonight. Since I decided to go with the steel backed guides, you'll notice that there is a difference in mounting. I got around this pretty easy. First thing I did was pull the metal spacer out of the left plastic guide. This was so I could use the same bolt to put back in where I took it out of since that also helps hold the oil pump. Also the steel guides have 3 mounting holes each rather than the 2 on the crap plastic ones. Since I was smart enough to keep the bolts out of the blown engine that was originally in my truck, I had extras so I just used them. If one decides to do what I'm doing and doesn't have that luxury, a trip to the hardware store would solve this problem.

I didn't take a picture of it but I noticed while it was all apart that the left tensioner arm had been worn all the way through the plastic and was riding on the aluminum. It was a small area and the chain looks fine so unless anyone advises otherwise, I am using the original chain.

Also I would advise anyone doing this job the way I am, that is, just replacing the guides, tensioners and arms without removing the chain, make damn sure you find a good way to lock the cam in place, even if it is just one at a time while you work on that side. I didn't and regretted it. I have the 6849 Ford Cam Master Tool Set, however when I bought it it was missing a couple pieces. I knew this when I bid on it and is why I got it for $130. Turns out the small roundish cam lock tools for the 4.6 are the ones that were missing. How freakin' convenient... Left side went fine, however when I had the right chain slack, the right cam jumped a crank tooth retarded. Luckily I heard it pop. I spent the next hour figuring out how the hell I was gonna fix it. Got it done, but just a word of advice to anyone else doing this, LOCK THE CAM!

 

[223thecure]

Also I would advise anyone doing this job the way I am, that is, just replacing the guides, tensioners and arms without removing the chain, make damn sure you find a good way to lock the cam in place, even if it is just one at a time while you work on that side.
Left side went fine, however when I had the right chain slack, the right cam jumped a crank tooth retarded. Luckily I heard it pop. I spent the next hour figuring out how the hell I was gonna fix it. Got it done, but just a word of advice to anyone else doing this, LOCK THE CAM!

I just did the same job a month ago without any special tools & had almost the exact same experience ... the left side remained lined up well whilst I replaced the guides & tensioner ... but the right side rotated a few teeth. Using a 1/2" drive extension bar, I simply put it thru one of the hole of the RH cam sprocket & 'levered' it up to the correct position using the head behind the sprocket to lever from.

This job always sound quite daunting but is actually very simple to do once you get your head around the 'fear' of getting it WRONG ! If you line up the marks on the sprockets with the shiny link on the chain before releasing the spring loaded tensioner ... you can't go wrong ! Double check & triple check your marks & all will be good

 

[rocco123]

I agree with 223. I just used a pipe wrench to hold the camshaft when torquing it

 

[Number4]

If it moves, you just have to count links between the timing marks. Make sure there's the same amount of links on each side of the chain. The different colored links just help so you don't have to count them.

 

[JakePSD]

Mine didn't have different color links so I counted them, at least 10 times, just to make sure. Since mine rotated backwards, and the valve spring tension was still wanting to push it more that way, I just put an 18mm wrench on the sprocket bolt put some tension forwards and reset the chain. A 3rd hand would have been helpful.

This job always sound quite daunting but is actually very simple to do once you get your head around the 'fear' of getting it WRONG !

EXACTLY! If I ever do this type of job again, which I will I'm sure, I'll have it done in no time.