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Discussion Starter #1 (Edited)
To start off I will let you know how to tell if this may need to be replaced. I had an engine noise coming from the top end toward the passenger side of the car. The noise got louder the higher the RPMs got. The two most likely suspect were the timing chain and the balance shaft chain. To check the timing chain I took off the valve cover and made sure the timing chain was tight around the cam gears and that I could not make any slack in it. To check the balance shaft chain (also runs the internal water pump) I took off the water pump access cover on the side. I was able to get a couple fingers inside to check the chain. This chain is also suppose to be tight but I was able to move it. This is how I knew the tensioner was probably bad or something else was wrong.

Floor Jack
Jack Stand
Piece of Wood
Screw Driver
Impact Gun
3/8" Ratchet
1/2" Ratchet or Breaker Bar
6" Extension
Harmonic Balancer Puller
10mm, 13mm, 15mm, 18mm, 22mm Sockets
5/8" Hex Key Socket
10mm End wrench
Torque Wrench
Think thats all but I may have missed something

Balance Shaft Chain Tensioner
Crankshaft Bolt (Dealer only can't reuse the old one)

The one online guide I have states it takes around 6 hours to complete. I would give yourself at least a full weekend. This will allow for the numerous beer breaks

First you will need to remove the following items. I will not go into detail as they are pretty self explanatory or there are other tutorials that will describe :

Passenger Tire
Inner Wheel Liners
Air Intake

Now that all of that is removed you will need to remove the motor mount. To do this support the engine with a floor jack with a piece of wood on top. There are 3 Hex keys bolts that attach to bracket to the engine and then (2) 18mm nuts that hold the mount to the unibody.

Now you will need to remove the serp belt tensioner. You may need to jack the engine up or lower it to be able to get a 3/8 ratchet attached to it. Once attached rotate the tensioner counter-clockwise to release tension on the belt and remove the belt.

This is where things get fun. You need to take off the harmonic balancer. This takes a 22mm socket and should typically come off with an impact gun. I however did not have such luck. I had to use an old school trick to break it loose. I had to take a breaker bar with the socket attached and wedged the bar between the axle shaft and the control arm. If needed have someone steady this while someone else bumps the ignition. This will cause the harmonic balancer to turn but the bolt to stay still and thus loosen. I still needed to use the impact gun afterwards to get it to come completely free.

After you get the bolt out you will need to take a harmonic balancer remover/puller with an 18mm socket to remove it.

Next is to remove the serp belt tensioner. There is an access hole that will line up with the tensioner bolt. You may need to lower or raise the engine again with the jack to get it to line up. Once lined up use a 6" extension and a 15mm socket to take the bolt out. Note be very careful not to drop the bolt in between the two access holes. I unfortunately made this mistake and had to retrieve it by making the access hole slightly larger and then using a magnetic tool to pull it out.

Now its time to remove the cover. To do this there are (10) 10mm bolts around the outside of the cover. I have tried to show all of them in the pics but it may be easier by looking at the picture of the cover removed. Once again you will need to move the engine up and down to be able to get to these. Some of the ones on the top I had to use an end wrench to get to. There is also one larger bolt near the middle of the cover by the water pump. I think this was a 13mm but it might be a 15mm.

Now that the cover is off we can see that there is slack in the chain near the tensioner guide. If I push on the guide like the tensioner is suppose to the slack is removed. You can see that when I push on the guide the slack is gone. This means the tensioner is bad and needs to be removed. To remove this remove the (2) 10mm bolts that hold it in place and maneuver it around so that thethe piston from the tensioner comes out of the guide

Now install the new tensioner using the original bolts. The new tensioner will come with a lock pin. This hold the piston in place. Don't remove the pin until you have it bolted in.

Now its time to put everything back together. All the bolts for the cover and the larger bolt by the water pump all require 18 ft lbs which is pretty much means snug with a wrench. You will want to make sure to put the serp belt tensioner on before the harmonic balancer otherwise you wont be able te get it between everything. The bolt for it I believe needs to be tightened to 33 ft lbs.

Next its time to put the harmonic balancer back on. Most people will tell you that you need an installer tool. I got one of these but it turned out to be useless as the adapters do not fit into the bolt area. I just lined up the balancer with the key on the inside and was able to push it back on fairly easy. I then used the old bolt to push it in the rest of the way. YOU WILL NEED A NEW BOLT for re-installation. These bolts are torque to yield bolts and require replacement any time they are loosened. Put the new bolt in and torque it to 74 ft lbs plus 75*

Almost done, put the serp belt back on and the motor mount. The hex key bolts get torqued to 37 ft lbs and the nuts get torqued to 74 ft lbs. Now put the intake, inner fenders, and wheel back on. Lower the car and your done.

1 Posts

Great write up!

I just had a shop change my water pump, simply because I didn't want to have to do this. They used my holding tool, but after driving out of thier facility I heard the dreaded whine from the chain area. Obviously the holding tool must of slipped or moved the slightest, causing the tensioner on the balance chain to ratchet out a click or two. I should be going back to the shop today to adress the issue, but in some way I'm fearing that they'll not be too willing to fix this even though it was them that caused it.
Worst case scenario, I may have to reset the tensioner myself. The only real issue I have with having to do so is the fact that I'm not set up with a compressor / impact gun for the crank pulley.
How essential was it to remove the motor mount and raise / lower to access all of the bolts for the cover?
I'm an ss LSJ, not that it really makes a difference though.

Definitely a great write up though, very detailed.
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