After all the threads lately about valve spring failure I'm starting to get a little worried. I posted these questions in another thread but thought I would create a new thread to try and answer a few questions I have about this issue.

1) Does this effect both LS1 and LS6 engines?
2) What years have been associated with the problem?
3) Are there any identifying marks on the springs or associated hardware that can positively identify bad springs?
4) Do we have any way of knowing how many on the forum have had this problem?
5) Is it always catastrophic when the spring breaks?
6) Since I'm beginning to get worried about this, who wants to come over and change my valve springs?

Please don't start flamin me if some of these questions have been answered already.

 

I'm not answering all those questions after reading your sig...seeing you have an 02 LS6......change your springs, and rest easy.

 

1) Does this effect both LS1 and LS6 engines?
I'm not sure, but I think more common on LS6 (yellow springs)
2) What years have been associated with the problem?
Again not sure, 01-02 are what I've seen mostly
3) Are there any identifying marks on the springs or associated hardware that can positively identify bad springs?
Not that I'm aware of
4) Do we have any way of knowing how many on the forum have had this problem?
No help here either, but keep in mind that only a certain percentage of owners frequent the forum
5) Is it always catastrophic when the spring breaks?
Valve hit's piston. Best Case: remove head and fix bent valve. Worst case, hole in piston.
6) Since I'm beginning to get worried about this, who wants to come over and change my valve springs?
If you go with Dual Valve Springs, then you'll have a bit more piece of mind since it wouldn't drop the valve if it broke, just clatter

EDIT: If you need help changing your springs, I'm not that far from you.

 

According to your profile, you have an 02 Z 06.
Be worried.
Change them out, like yesterday.
Good luck.

 

It's not a hard job, buy one of these:



And make it look like this:

 

EDIT: If you need help changing your springs, I'm not that far from you.[/QUOTE]

You may regret saying that.

 

I think you nailed it as usual. It's just not worth the gamble I guess.

 

Do you have a part number and vendor info?

 

I need that tool...gonna change mine as soon as I buy the car...

 

on sale at this vendor

http://www.speedinc.com/saleitem.cfm

 

That's a good price & worth every penny!

 

If you are stock, simply replace the springs with new GM or PAC 1215's. No need for duals where you will need to replace seats, seals, etc.

 

Excuse me if this is a stupid question, but do you need compressed air to hold the valves inplace while using this tool ? :o

 

No, if the piston is at the top the valve will go down about 1/8" before contact. You can also use the rope method.

 

The compressed air is so easy. Buy the hose kit from Summit Racing, part # is Moroso 62385 for $29.95.

 

Air method made me too nervous.
Being you all ready have the s/plugs out to use the air method.......

Why not turn the crank pully by hand,(15/16" wrench) you can look into each s/plug hole, via flashlight & see when piston is at top. No chance of having the valves drop.

Takes a little longer, but safer/ less nervous, using this method.
And of course, just my two cents.

 

So if the valve drops down 1/8'' you can still compress the spring enough for the clip to catch the stem?

 

Why would that make you nervous? If you have all the plugs out, the engine will easily turn over by hand, so you plug in the air tool, hook up the air hose, the piston will go down to BDC, as the air is pushing it, but the air holds the valves in place...Change the springs, go to the next cylinder.

Beats the crap out of trying the get the piston right at TDC, then hoping you can compress the springs enough to install the retainers and locks, while hoping that that 1/8" "drop" that was mentioned earlier, is able to be overcome by your spring compressor....

 

1) Does this effect both LS1 and LS6 engines?

From the data I've seen on this and other forums the vast majority of failures were in the Apr/May 2002 thru about Dec 2002 build dates. This would account for a few 2002 and 2003 model year cars. There were one or two prior to and after those dates, but the vast majority fall in that production run. Having said that, another member on here recently broke a spring with a Jan 2002 build date, same month as mine, so I got spooked and swapped out the springs.

2) What years have been associated with the problem?

See above.

3) Are there any identifying marks on the springs or associated hardware that can positively identify bad springs?

None that I'm aware of. The springs are yellow from the factory as are the GM replacement springs.

4) Do we have any way of knowing how many on the forum have had this problem?

There have been several attempts to collect such data but it has been inconsistent. It takes a few hours of poking around the forum to gather the information. Keep in mind you may run across the same member recounting their broken spring event in more than one thread.

5) Is it always catastrophic when the spring breaks?

It depends....The best case scenario is the valve is retained with no piston contact, problem immediately recognized and engine shut down to prevent further damage. Worse case is valve drops and motor eats itself. Problem is you just don't know and can't predict. Many have gotten off lucky, others didn't fare so well. That's the real crux of the problem, you just don't know.

6) Since I'm beginning to get worried about this, who wants to come over and change my valve springs?

I'd help if I was closer. I'd be happy to answer any other questions via PM if you so desire.

There are several threads outlining the procedure with pictures. They are all very good. I will add a few things I thought to be beneficial.

Take the alternator out. It is very easy and allows more room. I believe the service manual calls for it as well. Having said that the service manual also calls for removing some evap lines etc which is completely unnecessary.

Coil packs come off super easy. Push the electrical harness clip down slightly before unplugging it. Plug wires were kind of a bitch to remove. Work gloves are a must lest you want your hand coming out like they went through a meat grinder. I used a plug boot removal tool for grip and leverage. You have to get creative for a few cylinders (#7 & #8). Twist the plug boot a good half turn if at all possible and this will make removal easier. Buy new plug wires!! I ended up pulling one plug wire from the boot, but I did manage to perfectly save all the boot heat shields. Just don't grip the shield with the boot tool.

Removing the plugs wasn't as difficult as I had anticipated. Wasn't a walk in the park, but not impossible. A good combination of plug sockets, extensions, u-joint or wobbler drives will aid the process.

After that it's pretty easy. Buy a 8mm 3/8" drive socket if you don't have one. It's required for the rocker arms. Several have broken the 1/4" drive 8 mm sockets trying to remove the rockers. Those buggers were on tighter than I anticipated.

My biggest stumbling block was turning the engine over. I bought a 24mm socket to put on the front of the crank. Problem is the ratchet won't fit on the socket as the steering assembly is in the way. Try find a 24mm off set box end wrench. If not a 15/16" off set box end wrench will work (it's like 23.8 mm). The other option is to jack the back wheels off the ground and with the car in 5th or 6th turn the rear wheels to rotate the motor.

With the 15/16th wrench from the passenger side you can rotate the engine about 1/8 of a turn each time. I didn't opt for the compressed air method. I had planned on the rope method, but found even that problematic getting the rope started down the plug hole and fed into the cylinder. Perhaps I needed stiffer rope.

I rotated the engine watching the number 1 cylinder rockers and got it to TDC on the compression stroke. You're at a know starting point now. I removed the rockers and rocker stand "thingy", being careful to keep all the parts organized so they go back in the same spot. I then placed a bright colored drinking straw down the plug hole and you can feel the piston at TDC. Rotate the engine slightly either direction and you will see the straw move up or down and verify the piston is at TDC on #1.

The dual spring compressor tool is VERY useful and makes the job very easy. Tap the spring retainers slightly (I used the handle of a large screw driver) to break the varnish. Crank the spring compressor down on #1 and you'll see the retainers and locks loosen up. A magnetic pick up tool is indispensable for removing the little locks. Again keep the parts organized. Back off the compressor tool and remove the springs. I gingerly replaced the springs and never saw any valve move what so ever. (BTW, I bought the GM replacement springs and plug kit from Gene Culley and his crew)

Without rotating the engine go to # 6 and do the same thing. It should be at TDC of the exhaust stroke. Rotate the engine 90 degrees and do #8 & #5. Rotate 90 and do #7 & #4, and finally another 90 degrees and #2 & #3. Rotate another 90 and your back at #1 TDC. I put a piece of tape on the balance to aid in monitoring the rotation. (Firing order 1-8-7-2-6-5-4-3) I basically followed the same procedure as the service manual calls for torquing down the rockers. You want the lifter off the lobe and on the base circle.

Getting everything back together was easy. Gingerly thread the plugs so they don't cross thread.

When I was done it fire right up with not one issue. No codes, stumbling, excessive engine (rocker) noise, etc.

This got kind of long winded...sorry.

 

Hey, I really appreciate your feedback and I'll probably be using some of your tips. I may also PM you if I get in a bind.

I'm currently getting the parts and tools together to do it in 2 weeks. I'm also planning to change the spark plugs, wires and valve cover gaskets while I'm there.

Thanks again.