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SuperBob, Ford Senior Master, Mazda Senior
Category: Ford
Satisfied Customers: 2609
Experience:  18 years Ford, Lincoln, Mercury, Mazda Dealer ASE master, diesel certified. Specialize electrical
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Ford Mustang GT: I just replaced the timing chains/tensioners/chain

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I just replaced the timing chains/tensioners/chain guides on my 2000 Mustang GT (4.6 SOHC). Now the car idles okay, but is sluggish under acceleration and seems to have a different exhaust sound to it. It hasn't given out any codes yet. If the chains were installed out of alignment would it normally give a trouble code? Would it still idle smoothly?

Yes it will still idle smooth if you were off by one tooth on the camshaft sprocket, any more than one tooth would potentially cause valve contact with a piston and the engine would not run at all! The symptom that you described is conducive to having one or both of the cam sprockets off by one tooth! Did you set up the chains as described in steps 11 and 12 in the following instructions under the installation section?



Customer: replied 5 years ago.
Yes, I did align the marked links and sprocket marks with the crank at TDC. I'm just concerned because the original guide/tensioner guide on one side were gone (broken into pieces), but the chain was still in position. Also, I did reuse the original cam sprockets because the ones that came with the chain set were retained with a bolt while my originals were press-fit. They looked to still be in good shape and the outer dimension matched the new ones, so I decided to just reuse them instead. Is there a quick check to verify chain alignment short of opening everything up again?
Yes, you need to acquire a compression tester, where you will remove all of the spark plugs and have the throttle wide open, compare the compression of the right side of the engine with the left side of the engine on the fifth compression stroke and see if one side is lower than the other across the board, if you find that one side of the engine is equally lower on every cylinder, you will know that you do not have the timing correct!
Customer: replied 5 years ago.
I did a compression test starting with the front cylinders. Cylinder #5 had 200# XXXXX pressure while cylinder #1 had only 86#. I didn't continue because my compression tester hose adapter is now stuck in the #1 cylinder!!! (I'll get it out eventually). But in the mean time, with those numbers would it be safe to say the chain on my passenger side bank is probably off by one tooth? Any guess if its one tooth forward or back? The new chains didn't have copper colored links, but there were black ones that were on the opposite ends of the chains when it was flattened out. I was so sure I had the marks line up correctly, but I guess not. Oh well, here we go again....
No, there is not really any definitive way to tell if it is off one way or the other, if you still have the old chains, you can hold the old one up to the installed new one to compare or count the links between the copper links on the old and compare to the placement of the new one before you take it off!
Customer: replied 5 years ago.

I opened up the front cover. The black links on both cams were one tooth behind the notches on the cam gears. I moved both of them forward to align all three marks. I then rotated the chains a few turns and when the rotation came back to the point where all three marks should align, the links on the cam gears were again one tooth behind. Shouldn't they line back up at some point?


I think I really messed up. The chain set I picked up (Cloyes 9-0387SH) came with cam gears that had large center holes. Apparently my engine came with press-fit cam gears, and this replacement came with bolt-on gears. Since the gears were the same diameter, and I wasn't comfortable pulling and pressing on new gears, I decided to reuse the old cam gears being that they didn't show any excessive wear. On top of that I already threw out the old parts so I can't compare the cam gear tooth count or the number of links on the chains.


Are you familiar with the Cloyes replacement chain set? I counted 58 links on the Cloyes chain. Any idea how many links on a stock chain? Do you think I need to change to an OEM chain from the dealer in order to guarantee to get everything to line up properly with the original cam gears?

If they are both one tooth off at the cam gear, they should also be 1/2 tooth off at the crankshaft! It sounds like there is some difference in this aftermarket chain over the O.E. chain! I am not familiar with Cloyes chain, I think you should contact them and tell them what you did by using the factory sprocket with their chain and see if they know of any known problems by doing this, if there sprockets have just a minor amount of diameter difference from the factory sprockets it may cause this concern, Here is the link you need


Customer: replied 5 years ago.
Sorry, I just checked, the chain is also one link behind at the crank gear.
Customer: replied 5 years ago.
Sorry, I just checked again, the chain is actually looks like it is two teeth behind at the cam gears and the crank gear. I counted 21 teeth on the crank gear and 42 teeth on the cam gears (with 58 links on the chain). Does that sound right? Do these Windsor motors use the same chain link/gear tooth count as the Romeos?
Let me check on that, BRB
weather it is a romeo 2valve, romeo 4 valve or, windsor 2valve, the O.E. chains have the same part numbers
Customer: replied 5 years ago.
So mixing the old and new chains/gears should not cause a problem? I've seen listings for Ford 4.6's which stated 21 crank gear teeth and 116 chain links (two chains) which seems to match what I have. If I wanted to start from scratch, where should I start as far as where the cams and crank should be?
It should not matter unless the aftermarket sprocket you got is different from the O.E. sprocket, which would mean the chains are different! Did you hear anything from Cloyes yet?
Customer: replied 5 years ago.

Haven't heard from Cloyes yet. Not sure what kind of response time they have.


So is it wrong for me to assume that the marked chain links should realign with the crank and cam gear marks after the crank is rotated a few times? Or do the link count/tooth counts mean they won't line up regularly?

they should all be in alignment when the crank gear is in the correct location with respect to each chain, every time!
Customer: replied 5 years ago.

I've been trying to figure out why I keep coming out with different alignments. If my math is correct, these chain link and tooth counts don't match up. With 21 crank teeth, 42 cam teeth, and 116 links, the closest I get is: at 22 crank rotations (462 teeth) = 11 cam rotations (462 teeth) = 4 chain rotations (464 links). This would leave the chain two teeth behind the cam/crank gears (which seems to be where I am at right now). Just seems like the numbers on the gears and chains don't match. The chain would continue to "fall behind" by one tooth with each chain rotation and eventually realigning with the timing marks after 21 chain rotations (58 cam rotations/116 crank rotations).


Does this make sense? That as long as they maintain the same spacing from the timing marks (equal number of teeth behind on the cam and crank gears) they should be aligned properly?












Customer: replied 5 years ago.
I just rotated the crank with the chains installed. I lost count of how many revolutions I did, but eventually the marked chain links did align with the crank/cam gear marks at the same time with the crank at TDC. Does this sound acceptable as far as the chains being in the proper location?

Yes it does, my only real concern is that if the initial alignment that you did with the chain the first time you started the engine, if you had the chain off by two or more teeth, you may have had contact between some of the valves and a piston or two. I would advise running a compression test again with the front cover off and see if the compression is equal on all cylinders! Install the crank pulley to hold the timing chain sprocket and remove all of the spark plugs prior to doing this!

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Customer: replied 5 years ago.

I finally got everything put back together. It seems like the chains are lined up okay now.

There seems to be a miss when climbing uphill. I know I cracked the terminal side of one of the coils, but I checked it with an ohmmeter and it seemed to be alright. I'll change the spark plugs (since some of them had some tan build up on them). Any other suggestions?

Also, there is a bad surging at idle with the A/C on. I understand that this is often a sign the system needs a charge so I'll look into that as well.

Thank you for all your help in dealing with this issue. Your quick responses really helped keep things moving.

I am glad you got the chains corrected! an ohm check on the coil is not a conclusive test, at the dealer we use an oscilloscope to monitor the wave form of the coil when it collapses, what you can do is attempt a slight power brake in drive with the car stopped and the park brake set, see if you can duplicate the miss and if you can, then have an assistant learn how to make the miss happen while you disconnect one coil connector at a time to see if you can identify which cylinder does NOT make the engine run worse when it is disconnected, then you will want to swap that coil with a coil that DID make the engine run worse when it was disconnected, and re run the same test to see if the miss fire followed the coil or stayed on the same cylinder! if it followed the coil, replace the coil, if it stayed on the same cylinder replace the plugs! You do not want to hold the engine in a power brake mode for more than 30 seconds at a time without giving your torque converter about 10 minutes to cool before power braking again, so you will want to make quick work of your testing!
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