HOW-TO: Fix Your Timing Chain Rattle

[ILikeMy240sx]

Objective: To get rid of the "marble-in-tin-can" noise coming from the front of your valve cover by removing the two guides for the upper chain. The guides are considered unnecessary by Nissan as seen in their TSB. DO NOT REMOVE THE GUIDE FOR LOWER CHAIN.The procedure is written for a 96 S14 but should be similar for all DOHC engines.

Introduction:
There are three possible reasons why your timing chain is making the rattling noise.
1. Oil pressure is low: The tensioners that keep the timing chain tight are operated by oil pressure so if your oil pressure is low then the tensioner will not be working properly hence your chain will flap around and hit the guides.
2. Tensioner is stuck: If you have alot of oil gunk on your tensioner then the tensioner will be stuck and not extend out all the way to keep the timing chain tight.
3. Tensioner is broken: If your tensioner is mechanically broken then you need to replace it.
Having said that, before you follow this write-up it is a good idea to check your oil pressure. Also, in this write up I will not go over how to replace the tensioner but rather tell you how to clean it while it's still installed.

Difficulty: On a scale from 1~5 (5 being the hardest): 2/5

Time: Approximately 3 hours. Assuming you have no previous experience.

Tools:
-Metric Sockets including 27mm for the crank bolt
-Ratchet and wobble extensions
-Screwdriver
-Torque wrench
-Breaker bar (not necessary)
-Timing Light
-RTV Liquid Gasket

Procedures:
1. Set your #1 piston at TDC on compression stroke
-NOTE: You can tell you are at TDC on compression stroke by looking at the cams. As seen in the picture of the cams below, exhaust and intake cam lobes for #1 cylinder should be facing outward. So you might want to open the valve cover first then rotate the crank pulley. If the #1 cylinder cams are facing inwards then just rotate your pulley another 360 degrees until they are facing outwards.
-Jack up your car and crawl under your car
-Take a 27mm socket and a breaker bar and rotate the crank pulley clockwise using the crank bolt.
-Match the notches on the crank pulley with the needle as shown.



-Lower your car

2. Take off the valve cover
-Remove the spark plug wires.
-Loosen bolts as shown below.


-The bolts closest to the firewall might be a bit hard to get to because of wires and brake lines but try to push those away and wobble extension will help.

3. Remove the upper timing chain guide #1
-Note here the position of the cam lobes on #1 cylinder. They are facing outwards which means its at TDC on compression stroke. If the #1 cylinder cams are facing inwards then just rotate your pulley another 360 degrees until they are facing outwards.
-Remove the two bolts circled in yellow


-What my guide looked like. Check out the wear.


4. Take off the distributor.
-Now before you start taking off the distributor, make a making on the mount as shown below. This will help you with installing everything back with close to correct timing.


-Using a screw driver take off the cap(part that has the spark plug wires attached) off the distributor. There are two screws holding this. One on top and one on bottom. Once you take it off, you should see this. Make a marking on the rotor and the distributor so that when you install it, you know it's in correct position.


- Now, you are ready to take the distributor off. Unbolt the two bolts, circled in yellow, that are holding the distributor. One on top and one on bottom.


- Tug on the distributor with a bit of force. It should come out with a sound of "pop"

5. Take off the camshaft sprocket cover
- Here is a picture of the cover with location of the bolts and their torque specs. Please remember to distinguish between lb*in and lb*ft

- You might have to take a rummer mallet and gently tap on cover to get it off.

6. Remove the guide #2 and clean the tensioner
- Remove the two bolts, circled in yellow, to remove the guide #2.


-What my guide looked like.


-Now check the condition of the tensioner. If it's really gunked up with oil then spray some WD-40 and move the tensioner in and out repeatedly (many many times) until it comes out all the way and goes in all the way freely. Here is a video of what I am talking about. http://www-personal.umich.edu/...1.AVI
To make sure that the tensioner is all the way out, try pushing the tensioner towards the chain.

-Check the condition of the bottom tensioner as well. It it's stuck then do the same thing as the upper tensioner. Here is a picture of the lower tensioner


7. Install the camshaft sprocket cover
-Now your guides are gone and your tensioners are working again. It's time to install everything back together.
-Using a plastic scrapper of some sort clean the surface where the camshaft sprocket cover meets the engine. Be careful not to drop any gunk down the front cover.
-Apply your RTV liquid gasket as shown in the picture.

-Install the camshaft sprocket cover and torque to specs. Go easy on the tightening since the head is aluminium and you can easily strip the thread.

8. Install your valve cover
- Put your gasket in the valve cover as shown in the picture.


-Apply RTV sealant at the semi-cricle "ditch" in front of the camshaft and also in the back as shown in the picture.


-Install your valve cover and tighten as shown below. Torque spec is around 7~10 lb*ft


9. Install Distributor.
-Now this is the tricky part...
-If your car is S13, your distributor should look like this when #1 piston is at TDC on compression stroke.


-If your car is S14, you should align the distributor as shown below and it should look like this installed.


-If you made the mark on the rotor before, this would be a simple process assuming your engine did not move.

-Also, your rotor should be perfectly aligned with #1 spark plug wire as shown below.


-Rotate your distributor so that it matches the marking you made on the mounts previously. This should bring you close to the timing you had before.

-Please note the spark plug wire position and install them back.


-Make sure everything is connected and good to go. Start your car and check your timing. If its not in spec, disconnect your throttle position sensor and adjust your idle so that is around 700 +-50 and check your timing. If its out of spec, make sure you installed your distributor correctly and rotate your distributor accordingly to retard or advance timing.


Pat your self on the back and grab a bottle of beer. You are finally done with the infamous timing chain guide noise.

[Veriest1]

Nice right up. It was very informative and the pictures were great.

It'd be more usefull if I had a DOHC though.

[4felix20]

do i hear angels singing..!?

damn. thanks ALOT man. that is a very nice write up with VERY nice clear pictures too. i think you should get a free NICO shirt or something..

[ILikeMy240sx]

Thanx guys for the compiment.

Just giving back to the community that has given me so much.

[D1SR240]

Nice write up, now your sig kinda matches mine.

[ILikeMy240sx]

Ok I admit it... Yes, I copied the idea from you hehehehe.

[Tsukai240]

GR8 WRITE UP i'm probably going to use your instructions soon. ( I H8TE THAT DAMM RATTLE )

[phuphyter]

Can a mod sticky this in the tech forum?

[s13EastTN]

That picture of the distributor will certainly come in handy for getting my timing in place.

[spider_slayer]

this should definitally be a sticky thread

[DammitBobby]

I have read how to do this many times but this article is the best I have seen. Please make this one a Sticky!! Great Job!

[ILikeMy240sx]

Thank you all for your compliments.

Mods, do feel free to move it to technical and make it a sticky there if youd like.

[Jookmasta]

great write up. i havent seen anything like this b/f when it came to our timing chains. u may have just saved the existence of all 240s...............

[skydragoness]

You're the man now dog!!!

I've been real upset/worried/nervous/paranoid about my timing chain, it's not going bad yet. But i do hear the tell-tale rattle now that i have 113k on the odo. This writeup makes it look easy enough that me and my bf could tackle it. Since the FSM seems so cryptic, and pictures/specific guidlines REALLY help. This is a simple way of getting in there and cleaning house/checking out the guides. And since my mechanical fan and the shroud are gone, there's definitely plenty of room for me to try this out.

You ROCK.

[gabossie]

Very nice write up. Only one little mistake, the KA block is iron, not alluminum

[ILikeMy240sx]

Yes you are right the bottom block is iron but the head is Aluminum.

edit: WTF I said block is alum in the write-up lol fixed. thanx for the correction.

[Zyphar]

very nice how-to! very informative and visual!


just 2 quick questions...

1. You stated that you needed a timing light. In what step do u use it ? or did you not use it at all?

2. In order to reach the lower tensioner and guides another cover must be taken off correct ?

[ILikeMy240sx]

1. After you put everything back together... you have to make sure that your timing is correct because you are taking off and putting on the distributor which adjusts the timing. If you make a mark on the mount/rotor I described and you did not rotate the engine then you probably won't need it but its always good to check.

2. Yes the front cover must be taken off which is a long process and a PITA procedure if your engine is in the car from what I hear... BTW, you can still see and play with the lower tensioner with only the camshaft sprocket cover off.

[jgtc_s14]

thanks very very useful

[Silverbullet91]

Is the picture above showing which way to rotate the distributor for advancing/retarding correct? I thought that the rotor button turned clockwise and therefore turning the distributor clockwise would retard the ignition and counter-clockwise would advance the igniton. Am I wrong? Somebody please correct me.

[ILikeMy240sx]

Nope, the way I have it in the picture is correct. I originally thought the same thing but it turned out that I was wrong.

[Tsukai240]

once again thanks for the great write up. 2 questions:
how do you incerase your oil preasure
what are the part numbers on the new tensioners

my timing chain is sooo loose i'm having very noticeable timing drift. (oh and its fugging NOISEY)

[ILikeMy240sx]

your oil pressure is low when something is wrong for example oil pump, oil filter and maybe the oil pick up in the oil pan, or something is blocking the passage...

You can go to sites like midwaypartsteam or nissanparts and search for timing tensioner for your car and it will give you the part #

[nismofly]

somebody do this for the SOHC!!

not going to be me either lol...im waiting for it so i can do it myself

[240sx2nr]

dope write up.... imma for sure do this on my zenki cause the tick is super annoying

[sanioll]

god, this is a great write up, you relieved so much from my shoulders.

So thats where the noise is coming from. its simply the guides.

youre a genious!

i'm simply not going that deep, i have to look into FSM learn at bit more about the engine before going that deep.

But, can I just remove the top guide and leave the bottom guide inside?

I think on mine its only the top guide making that noise. I hope its okay to remove only one. this doesn't cause any kind of looseness in the chain does it?


Modified by sanioll at 3:48 AM 3/21/2005

[ILikeMy240sx]

You can just remove the top guide but alot of people have reported that even with the top one removed, they still hear slight ticking and trust me most of them regret that they didnt remove the #2 guide while they were removing the #1...
As seen in the picture above, its clear that #2 guide also has wear on it. Sooner or later depending on the condidion of the tensioner, that wear is going to get bigger and bigger until the guide snaps, falls into the front cover and breaks the chain and kaboom (worst case scenario)... I suggest you remove the side guide while you are at it.

BTW, the chains are hitting the guides because the chain is loose. So be sure to clean and check the condition of the tensioner instead of just removing the guides. You can do this for both bottom and top tensioner with the camshaft sprocket cover off so go ahead and do the entire job while you are at it

[sanioll]

see i'm still a virgin when it comes to engines, set tdc at compression stroke, etc... i donno what that even means. so i gotta look into FSM more and learn a bit more to get more comfortable doing it

i'll just remove the top guide for now, also my valve cover is leaking since i switched to mobil 1. so i gotta take it out, probabbly replace the gasket and apply some seal.

[ILikeMy240sx]

TDC - top dead center. When the piston is at the highest point.

Compression stroke - This is the stroke of the piston that compresses the fuel and air mixture before cumbustion.

TDC at compression stroke. The highest point of piston when its compressing the fuel and air mixture. So TDC at exhaust stroke would be the highest point of piston when its letting the exhaust out of the cylinder.

Hope this helped. If you have any questions feel free to email me or im me or post here.

[sanioll]

sow how do youj know that TDC is at compression stroke? Do you start and stop the engine until its aligned??

^--blonde/redneck style --^