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Discussion Starter · #1 · (Edited)
I've had to pull the timing chain tensioner one too many times by now, removing the valve cover every single time gets real old. Here are some steps for replacing it fairly quickly.

Part numbers for replacement parts:
13070-2J203 - Timing Chain Tensioner
13069-53J00 - O-Ring
13079-2J200 - Timing Chain Tensioner Gasket

Remove 1st cylinder's spark plug and rotate the engine by hand till it's at TDC (Top Dead Center). You'll know it's at TDC by looking at these three items:

Crank is on mark 2 from the left:


You should see the piston in the first cylinder:


Also the Intake and exhaust cam lobes will be pointing away from the center, since we can only see the intake lobe should look like this:


Remove the oil filter and start loosening the nuts, don't loose the lock washers. I used a towel to trap them and the nuts.



Reason for pulling the TCT out was to replace the gaskets, you can see the other one ripped when I tried to remove it.


TCT compressed and ready to be installed


New gasket installed


The tensioner has a U fork, it sometimes wont go into the chain guide properly, you'll know when it's in when enough threads are visible to screw in the nuts. I tightened one nut without the washer until there was enough threads to fit the other nut and washer, then removed the first nut and added the washer in front of it.


After everything is tightened and oil filter is installed back, rotate the crank to make the tensioner extend out, this helps reduce the chance of the chain jumping a tooth when you go to first start it.


After that reinstall the spark plug and start the engine, mine stilled rattled for a few seconds, probably because the TCT was empty from compressing before installation.
 

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I've had to pull the timing chain tensioner one too many times by now, removing the valve cover every single time gets real old. Here are some steps for replacing it fairly quickly.

Part numbers for replacement parts:
13070-2J203 - Timing Chain Tensioner
13069-53J00 - O-Ring
13079-2J200 - Timing Chain Tensioner Gasket

Remove 1st cylinder's spark plug and rotate the engine by hand till it's at TDC (Top Dead Center). You'll know it's at TDC by looking at these three items:

Crank is on mark 2 from the left:


You should see the piston in the first cylinder:


Also the Intake and exhaust cam lobes will be pointing away from the center, since we can only see the intake lobe should look like this:


Remove the oil filter and start loosening the nuts, don't loose the lock washers. I used a towel to trap them and the nuts.



Reason for pulling the TCT out was to replace the gaskets, you can see the other one ripped when I tried to remove it.


TCT compressed and ready to be installed


New gasket installed


The tensioner has a U fork, it sometimes wont go into the chain guide properly, you'll know when it's in when enough threads are visible to screw in the nuts. I tightened one nut without the washer until there was enough threads to fit the other nut and washer, then removed the first nut and added the washer in front of it.


After everything is tightened and oil filter is installed back, rotate the crank to make the tensioner extend out, this helps reduce the chance of the chain jumping a tooth when you go to first start it.


After that reinstall the spark plug and start the engine, mine stilled rattled for a few seconds, probably because the TCT was empty from compressing before installation.
Nice write up CovertRussian! This must be another Nissan engine because I just changed out the tensioner and gasket on my 2000 P11 and did not have to do all the work you did. I juat removed the 2 nuts and washers, compressed the tct, inserted it the hole, installed the washers and nuts, torqued em down, started the motor....done. Nice and quiet and no leaks.
 

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Discussion Starter · #4 ·
An SR20 is an SR20 no matter how big or how small ;).

I've done it the way you said more then once, but I've also been going through timing chain tensioners every couple years. So either the used tensioners are going out or that method really stressed them.

That method is actually really dangerous and that's why I went with my new method above. Reason is if your engine is not TDC when you pull the chain tension the cams can rotate independently and jump teeth. If you don't rotate the crank slowly after the install, you run the risk of jumping more teeth when the powerful starter cranks the motor.
 

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An SR20 is an SR20 no matter how big or how small ;).

I've done it the way you said more then once, but I've also been going through timing chain tensioners every couple years. So either the used tensioners are going out or that method really stressed them.

That method is actually really dangerous and that's why I went with my new method above. Reason is if your engine is not TDC when you pull the chain tension the cams can rotate independently and jump teeth. If you don't rotate the crank slowly after the install, you run the risk of jumping more teeth when the powerful starter cranks the motor.
I understand your logic completely and I suppose I got lucky in the method I used. I got lucky twice because the first time I installed the new tensioner I reused the old gasket and ended up with a leak so I had to pull it again and install a new gasket. Perhaps you could enlighten me in regard to the number one cylinder being at TDC preventing the chain from slipping off a gear. I understand the mentality for manually rotating the engine to allow the tensioner to unlock.
 

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Discussion Starter · #7 ·
I understand your logic completely and I suppose I got lucky in the method I used. I got lucky twice because the first time I installed the new tensioner I reused the old gasket and ended up with a leak so I had to pull it again and install a new gasket. Perhaps you could enlighten me in regard to the number one cylinder being at TDC preventing the chain from slipping off a gear. I understand the mentality for manually rotating the engine to allow the tensioner to unlock.
It's actually the same reason you TDC the first cylinder for cam install. When cyl 1 is at TDC intake and exhaust cam lobes for that cylinder are in "off" portions of the cams, as in it's not trying to open the intake or exhaust valves for cylinder one. The idea is, if the valves are not being forced open on cylinder 1, which is the closest cylinder to the tensioner, the cams are less likely to spin and skip teeth when you remove the chain tension.

This is even more important when installing cams. If you don't have cyl 1 at TDC you can actually break the cams in half as you tighten them down due to uneven pressure from the cam caps.

Nice writeup! I thought everyone did it this way, ha ha whoops!
It's dangerous to assume these things if your trying to help new folks :teeth:. That's why I thought about the process and and figured the safest "quick" way of replacing the tensioner. Last thing I want is someone blaming me for their dead motor :).
 

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This is even more important when installing cams. If you don't have cyl 1 at TDC you can actually break the cams in half as you tighten them down due to uneven pressure from the cam caps.
I've seen this happen too many times I care to admin when people install JWT cams on QR25DE blocks. Car will crank over and they THOUGHT it was at TDC but they weren't or weren't "enough" (half one way half the other) and cam will snap and take the cam caps with them, if your lucky, block if you aren't.
 

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Oh man that's nuts, you hear of a few broken cams on SR20's but nothing that major!
JWT's instructions for installing the cams have tons of warnings about it. Plus you HAVE to torque the cam caps down in a particular order as to not strain the cams or they'll snap due to that as well.
 

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Discussion Starter · #12 ·
Man I'm guilty of that, I didn't use at torque wrench when replacing cams, just good-n-tite all the time. Luckily no issues so far but I think I'll be pulling my valve cover here soon and retorquing everything to be safe.
 

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Discussion Starter · #13 · (Edited)
Nice write up CovertRussian! This must be another Nissan engine because I just changed out the tensioner and gasket on my 2000 P11 and did not have to do all the work you did. I juat removed the 2 nuts and washers, compressed the tct, inserted it the hole, installed the washers and nuts, torqued em down, started the motor....done. Nice and quiet and no leaks.
I know this is really late, but I never replied to the first part of your message. My motor is a 2000 P11 SR20 too, but with a low port oil filter housing, which puts the filter right behind the tensioner, this is how 94-99 guys would have it too.

I've recently went back to the P11 style oil filter, and yes the tensioner is much more reachable now.

While I'm here, reuploaded the pictures to the site.
 

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Discussion Starter · #15 ·
It's in the exact same spot, but your manifold design is different, though I think it's even easier to get to. Takes a minute to go outside and confirm though. ;)
 

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I believe I caused my timing chain to skip a tooth on at least on of the cam sprockets but I do not know which one. (I rotated the crank pulley in both clockwise and then counterclockwise while trying to gett the crank pulley to TopDeadCenter. The tensioner was not extended; hence, no tension was on the chain, which allowed the chain to skip a tooth on a cam sprocket. Now, if I rotate the engine clockwise, eventually I come to a point where I can no longer rotate it and have to rotate it counter clockwise in order to be able to set the pulley back to the TDC mark.
How I know the chain skipped a tooth:
There are only 18 chainlink pins between the marks on the cam sprockets, and from what I understand there should be 20 (11 links, counting just the inner pin on the two outer links)
JIM WOLF: SR20 CAMSHAFT INSTALLATION
Resetting Timing When Chain Has Skipped a Tooth on Cam Sprocket(s)
Setting the Timing Chain on SR20DET engine
Setting the Timing Chain on SR20DET engine

Cam Install
BEWARE: Torque Specs are Key


It should look like this----> The X's represent the two marks on the cam sprockets.
O-X-O O-O O-O O-O O-O O-O O-O O-O O-O O-O O-X-O (11 links, 20 pins btwn. marks)
-------1 2-3 4-5 6-7 8-9 1011121314151617181920-------

Mine looks like this ---->
O-OXO-O O-O O-O O-O O-O O-O O-O O-O O-OXO-O (9 links, 18 pins between marks)
--------1-2 3-4 5-6 7- 8 9-101112131415161718--------
  • I am wondering, if I rotate the engine manually by turning the crank pulley and the tensioner is not engaged (there is no tension on the chain) and the chain skips a tooth on the cam sprockets, how do you tell which cam sprocket's tooth got skipped?
  • Also, how do you go about resetting the cam sprocket and/or cams to their correct positions?
I understand that at TopDeadCenter the cam lobes for cylinder 1 have the narrow part of their lobes pointing outward, intake side pointing toward the firewall, exhaust side pointing toward the front bumper.
  • If I set the crank pulley at TDC (lining up the pointer with the second notch from the left on the crank pulley) loosen the cam sprocket bolts and put the intake cam sprocket's "dowel" pointing to 10 o'clock and the exhaust cam sprocket's dowel pointing to 12 o'clock, WILL THE CAM LOBES BE IN THEIR CORRECT POSITIONS ALL THE WAY DOWN THE CAMS, OR WILL I HAVE TO UNFASTEN BOTH CAMS AND ROTATE THE INDIVIDUAL LOBES TO THEIR CORRECT POSITIONS?
 

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UPDATE:
I reset the timing chain across the two cam sprockets. First, I put the motor at TDC, using the marks on the crank pulley as my reference point. (2nd in from the leftmost mark)
I removed the intake cam's sprocket bolt and removed the sprocket. I pulled the chain up and off of the exhaust cam sprocket, pulling upward from the direction of the crank shaft. I then rotated the exhaust cam a bit to make sure that the mark on the sprocket would be at 12 o'clock once the chain was engaged with the sprocket. I laid the chain across the exhaust cam sprocket , maintaining the tension on the chain and pulling across to towards the intake cam sprocket.
I counted 20 chain-link pins inside the two cam sprocket marks and positioned the chain on the intake cam sprocket so as to maintain 20 pins between these two marks. This time the outermost link straddles the mark on either cam sprocket. (Before it did not.)
I fastened the intake cam sprocket into place on the cam, lining it up via the dowel key (pointing to 10 o'clock), and installed the timing chain tensioner.
I rotated the crank manually for at at lease 2 full rotations of the motor, which is 4 revolutions on the crank pulley.
PROBLEM?:
When I rotate the crank manually, there is no slack in the timing chain.
When I relax the torque on the ratchet I am using to crank, I am able to create slack in the chain by pulling downward on it between the two camshaft sprockets. There is enough slack in it to allow it to hit the upper timing chain guide if I press upward on it. This slack is not present when I am rotating the crank shaft manually.

I do not know if this slack is normal, or if the chain has too much slack in it.
If this slack should not be there, and the tensioner did not solve the problem,
I have read that it is likely due to worn chain guides or even a stretched timing chain.
The ratcheting mechanism on the old tensioner seems limp and does not engage against the tensioner's teeth.
What causes this ratchet in mechanism to fail?
 

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PROBLEM?:
When I rotate the crank manually, there is no slack in the timing chain.
When I relax the torque on the ratchet I am using to crank, I am able to create slack in the chain by pulling downward on it between the two camshaft sprockets. There is enough slack in it to allow it to hit the upper timing chain guide if I press upward on it. This slack is not present when I am rotating the crank shaft manually.
I do not know if this slack is normal, or if the chain has too much slack in it.
COULD SOMEONE PLEASE TELL ME IF THERE IS SUPPOSED TO BE SOME SLACK IN A TIMING CHAIN WHEN THE TENSIONER HAS JUST BEEN INSTALLED AND IS ENGAGED ON THE CHAIN GUIDE?
I have not cranked the engine yet.
If this slack should not be there, and the tensioner did not solve the problem,
I have read that it is likely due to worn chain guides or even a stretched timing chain. IS THERE A WAY TO TELL WHICH, WITHOUT REMOVING THE FRONT COVER?

The ratcheting mechanism on the old tensioner seems limp and does not engage against the tensioner's teeth.
What causes this ratchet in mechanism to fail?
 
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