http://forums.corvetteforum.com/c5-z...as-broken.html

I am now a believer in just replacing them as PM. All appears good, but just one spring broke (1st cyliner on right second lifter in). see my post running now

 

I ordered Pac 1218 today and the tool for the springs......... where do I get detailed instructions on how change them with the proper TQ specs on the rockers and in what order they go in?

Thanks for any help

 

Rockers should be tightened to 22 ft/lbs

Changing the valve springs is pretty easy.

1. Disconnect battery

2. Remove Fuel Rail Covers (FRC's)

3. Remove plug wires and plugs.

4. Remove coil packs and brackets.

5. Remove valve cover.

6. Remove rocker arms and push rods. (keep them in order and put them back exactly where they came from)

7. Thread air holding tool into spark plug hole of the cylinder of the first two valve springs you wish to remove.

8. Attach air compressor line to air holding tool at which time the cylinder will immediatley pressurize with air.

9. With a rubber or plastic mallet, give a couple light taps to the top of each valve spring your removing. This helps break the valve keepers free.

10. Using the valve compressor tool (depeding on which one you have), begin compressing the valve spring down over the valve stem.

11. Have a good magnet ready to catch the valve keepers from falling as the spring compresses down.

12. Once the keepers are removed and in a safe place, start decompressing the valve spring and remove it off of the valve.

13. Remove the retainer off of the old spring and put it on top of the new spring.

14. Put the new spring over the valve and reattach your valve spring compressor and begin compressing the new valve spring.

15 Once the spring is compressed, reinstall the valve keepers. Be very careful not to drop the keepers. It helps to use vasoline to help hold the keepers into the groove in the valve stem.

16. Once the keepers are in place, you can slowly start decompressing the valve spring. Make sure that the keepers stay in place and once the spring is fully decompressed, remove your tool.

17. Give the top of your valve springs a couple of light taps to ensure the valve springs are properly installed and the keepers are secure.

18. Repeat the process (one cylinder at a time) until you have replaced all 16 valve springs or you have completed one side of the engine...however you want to do it. I did it one side at a time.

19. Reinstall your pushrods and rocker arms and torque to 22 ft/lbs.

20. Check everything over and recheck...and recheck.

21. Pour a small amount of motor oil over all the new valve springs and rockers. This will help with lubrication on intial start up.

22. Reinstall valve cover, coil pack bracket and coild packs.

23. Reinstall plugs and wires. (good time to install new ones if needed).

 

The valve spring tool that I used:



PAC 1218 Springs next to the stock LS6 Spring:

 

I had always worried about those springs, how annoying on such a sophisticated car.

I bought the comp 918 springs and the average install is $300. $500 total. Not only do I not worry anymore but the valvetrain noise at idle is much quieter.

 

#19 Just tighten them down to 22LBS down one side then the other? With the lifter up or down it does not matter?

I also have the Proform tool #67605 on the way.

http://www.jegs.com/i/Proform/778/67...ductId=1631816

 

Yep. The nice thing about LS engines is that you don't have do adjust valve lash like the older small blocks. Just torque the rocker arms to 22 ft/lbs.

I have read that many have used and liked the Proform spring compressor. You shouldn't have any problems.

 

I have built many Gen 1 SB but this is my 1st time working on the LS engines.

Thanks for your help,

Sid

 

Read this ... and pay attention to Post #7.
http://forums.corvetteforum.com/c5-t...reinstall.html

You guys doing the valve spring replacement ... use the search function, as there are about 20 threads that talk about how to do the swap-out.

 

I know this is the "proper procedure" according to the GM tech manual but I have never done this on any of the LS engines I have worked on. This includes head and cam swaps and nitrous and FI engines. I have never had (or heard of) an issue when you torque the rockers with the valve open. Inward out is the method I (and many others that I know) have always used.

I tend to think that people get so paranoid when working on their own engine because it's a "Corvette". It's pretty much the same old LS engine that GM put's in about every vehicle that has a V8 option. Just different configurations and HP levels. All LS engine family.

Maybe it's just me... but swapping out some valve springs on a C5 ZO6 is easier that swapping spark plugs on a 4th get F-Body any day of the week.

Don't over think it and just do it.

 

like i said guys just check out my threads from when my broke back in august & the video that i also made once i got it back up and running. for those of you that broke a spring and thats all that happened to your car, consider yourself very luck, it could have been worse. i truely believe that if i had been cruising at 70+ when it happened instead of doing 20mph right in front of my house, it would have grenaded the engine.

 

I changed mine last nite......

 

How did it go?

 

It went fine ruined a few plug wires but Jegs ships till 9:00pm so I got them in today,so It is just sitting there waiting for the wires then turn the key.

Thanks for your help,

Sid

 

I did mine around the 40k mark, I count valve springs as a wear item. Too many horror stories, did them with a buddy and it alot cheap then a new ls6

 

I have an '02 Z06 and although I appreciate that the chances of having a spring failure are 2% ~ 3%, I also realize "the penalty for failure" is pretty high. So I'm going to change my springs to make sure I'm not one of those 2%'ers.

The question I have is, will GM performance parts #12499224 for $60 fix the problem just as well as $190 PAC 1218 springs will?

If I understand correctly, the problem was caused by a bad batch of springs from the supplier in the 2002 ~ 2003 time frame. So new GMPP springs should ensure I don't have one of the bad springs.

I'm not looking to install a higher lift cam, and I don't race the car, so what benefit would the PAC springs give me for the extra $130?

I'm not adverse to spending the extra money if there is any tangible benefit, but if new GM parts will solve the problem, that extra $130 will pay for the spring compressor, new valve seals, and beer.

 

Supposedly, the new springs from GM performance work fine ... I haven't heard of any issues with them. I think they are now blue in color and made in Mexico.

Here's some PAC 1218s for $165 to your door (free shipping over $100).
http://www.speedinc.com/cont.cfm?cid=C0000794

I went for the PAC 1518s ... a few extra bucks is worth the insurance that they will be reliable and long lived for me.

 

Here is where I got my Pac 1218

http://www.carshopinc.com/index.php

$147.00 to the door and ordered at 4:50 pm and got the next day

Sid

 

I have done it several times and I have never had an issue with the rocker arms with just torquing them down on one pass. I use red lock tight on them and torq them to 22 foot pounds and enjoy the car with a better feeling, because I am confident that my new springs will not snap.

 

I was doing 70 mph when my valve spring broke. Your right. it will grenade your engine. Mine busted number 1 piston, broke the rod, 2 holes in the block and 1 in the oil pan. No warning at all when it broke.