Quest for Timing Chain Rattle: Complete

[misnomer]

OK, my digital camera is pretty much dead, so I have no pictures for y'all, but I did promise a writeup of sorts :-)

This is for the DOHC ('91-98) KA motors ONLY!

My motor had been making a steady rattling sound at idle, went away at higher rpms. I had already removed my upper timing chain guide for more annoying prior rattling. Before getting into this, make sure the rattling sound is coming from the valve cover towards the front of the engine. No point ripping everything apart to find the issue is something else. Use a big beefy screwdriver or a solid metal pipe to verify this.

Tools: Ratchet, 10mm, 12mm, 14mm sockets (you may need other sizes, dunrecall for sure).

Parts: RTV (silicone sealant), valve cover gasket (optional, only replace if the old one seems dry or was leaking profusely).

-Start by removing the valve cover, four bolts along each side, three on the top, 12mm iirc. Losen and remove the vacuum tube at the top.
-Unscrew the black injector connection housing (doesn't need to be removed, just loosened). Pull out your spark plug wires. You can mark them if it makes you feel better, but they are labelled on the distributor cap (cylinder 1 being at the front of the engine).
Lift up and remove the valve cover. You will now see your timing chain at the front of the motor.

If you still have an upper timing chain guide, it's a good idea to remove it now.
-Remove the guide over the top of the chain by losening the two bolts into the block (10mm iirc). Pull out the guide and hang it on your wall, or discard it, or something. In some cases (mine) the guard will have already been snapped, just pull it out and chuck it.
It's quite possible that this guide is your only problem, if you think it is, skip down to the *, save the effort of getting into the upper timing cover.

Now you must remove the distributor ('91-94 models, this may have changed for '95 and later. if it has, you have to be the clever one, I can't do all your work for you ;-) ).
-Remove the distributor cap. Nissan caps already have the cylinders numbered on them, so don't worry so much about keeping the wires in order if you have to take them off. Use a flatblade screwdriver to losen the plastic wire cover.
-Unscrew the two screws at the top right and bottom left looking head on at the distributor.
-MARK THE POSITION OF THE ROTOR! Use a felt tip pen to indicate where the rotor is pointing before you remove the distributor. If you don't, you will have to reset the spark timing (as I did). A lot of hassle that is easy to avoid.
-Remove the distributor by unscrewing the two 12mm adjustment screws and pulling the whole shebang out, it helps if you turn the cap counterclockwise a bit to remove it from it's gears.

Pull off the upper timing cover. I don't recall how many bolts there are, but some are 12mm, some are 10mm (those into the head are smaller).
-Unscrew the bolts on the upper cover, check where they come from first :P Don't forget the bolts into the head and the two bolts behind where the distributor was.
-Pull off the cover, probably easiest to grip from the distributor hole. If it doesn't come out relatively easy, double check to make sure you have all the bolts.

Check your tensioners. The upper tensioner is on the left side of the chain, use a flat bladed screwdriver to compress and extend it. If you get the urge, you may want to replace it. Do the same with the lower tensioner (you can't reach it to replace from here, but you can test it).

Remove the lower guide on the upper chain, it's on the right side of the chain.
-remove the two 10mm bolts and pull it out.

And I'm out of time, I'll add "putting **** together" in a couple of hours.

Cliff notes: Screw you and read the whole thing, hippie!

[misnomer]

Hmm, what's wit h the "180 minutes or no edit for you" deal?

Anyhow, putting **** together:

Clean the mating surfaces for the timing cover with a rag and perhaps a very very light amount of degreaser (remember, oil is s'posed to be in your motor, don't degrease it :P)

Put down a layer of RTV around the timing cover and slap it back on. There are two pins out of the head to help guide it on. I used a mallet to tap it into place. Screw the cover back in using a star pattern (go opposite corners to make certain it goes in level). Do the head side first, then the bolts going into the shortblock. I don't have the torque specs handy, maybe I'll add them later. On the head side, you don't want much, 10-12 lbs mebbe. Remember you are going into aluminum, which will strip easily.

Reinstall the distributor:
-Align the rotor slightly counterclockwise from your marking point and slip it in, remember it will turn a bit when you push it in.
-Twist the distributor until you are aligned with your mark and bolt it in.
-Put back on the cap, lower plastic guide, wires (to appropriate connectors, they should be labelled on the cap, if not it's 1-2-4-3 starting left and going clockwise), and outer wire guide.

* Slap back on the valve cover:
-Clean off the gasket and mating surface, put a thin layer of motor oil on the gasket, and slip the cover back in place
-put in the screws in a star pattern, don't torque them down yet, just get them in place. Once all of them are in, torque them to 10-12lbs (if you don't have a torque wrench. .. be careful :P)
-Screw back in the injector connector housing, reattach the vacuum tube.

Wait a day for the RTV to cure.

Fire her up, enjoy the best sound your car has never made.

If it doesn't fire up, then you obviously screwed up and there's nothing I'm going to do about it. Use at your own risk. Has been known to cause cancer in laboratory animals. For entertainment purposes only. Caveat Emptor.

Again, no cliff notes, yah lazy bastard.

And please, somebody reply to my threads, make me feel that my time was worthwhile. Lie if you have to :-)

[240Stilo]

Let me get this straight, you removed the two upper chain guides, checked the tensioners, and the rattling went away correct?

[misnomer]

Correct.

[mrmurphz]

I took the upper chain guide off yesterday and I still have some rattling. I guess its the lower guide. Do I need to take the valve cover off again to access any bolts or do I jump straight to the distributor part? Nice instructions btw.

[misnomer]

The RTV that's already on there could be holding it, try tapping it away from the motor a bit with a mallet and "suitable tool." Remember there are bolts going down into the block and back into the head. There are also two pins sticking out from the head to guide it into place, it needs to come out, not off to the side, not down. I was able to pull mine fairly easily by gripping the hole where the distributor was and pulling out, it swung around and came out.

The valve cover has to come off for the upper timing chain cover to come off. MAKE CERTAIN YOU DO NOT REMOVE THE LOWER TIMING CHAIN GUIDES. Those are required. Just remove the guides on the upper chain. I expect the upper chain guides are what you meant, but just trying to be safe :P

As far as timing goes, to start with you need a timing light, and a relatively dark area to work in. Hook up the light to the battery and clip the inductor on the #1 spark plug wire. Start the car, and point the light at the crank pully. You should see a series of marks on the pulley, mostly white, with one red one. If I'm correct, the red is 0, and the whites increment at 5 degrees. (with them being -5, 0, 5, 10, 15, and 20). You determine where you are by the little needle thing that sticks out over the pulley on the drivers side.

To adjust, you losen the two bolts on the distributor and twist the entire housing. When you twist the housing, you will see the marks on the pulley shift position, and you'll notice a change in idle. I set mine to 20 degrees, read somewhere that was default, but advance slowly and listen for pinging (I'm high altitude, so knock isn't so much a problem). Twist the housing slowly until the last mark lines up with the needle.

It's also worth note, when you rev the engine, you should notice the timing advance (the marks will move counterclockwise of the indicator needle).

[sykikchimp]

excellent work misnomer! ARCHIVE!