Just ordered the XE 224/230 cam kit from Combination Motorsports with their valve springs. I was on Streetillusions website looking at the valve spring install and they say to just make sure piston #1 is at TDC and you are good to go the swap out the springs for cylinder 1 and the same (TDC for the springs you are working on) for each corresponding cylinder. I thought you had to use compressed air in the spark plug hole to keep the valves from dropping into the cylinder? Or, by having the pistons at TDC you don't have to worry about the valves dropping ? Just need to know before I make something simple into a huge headache!

Jeff

 

all you do is take your rockers off put compressed air in the cylenders and pull the springs. as soon as you put the air in the cylender the piston will go to bdc. and the air keeps the valve from falling. you need a special fiting all i used was a old sparkplug with a air fitting welded to it (remove ceramic first).

 

The TDC per cylinder method will work, too. As hard as it is to get plug access, the TDC method seems less trouble.

 

So, if I do the TDC method I don't have to worry about the valves dropping correct?

Jeff
(sorry, sometimes I am an idiot!)

 

They will go down a little (~3/4") until they hit the piston. When you do the first one, hold on to the valve and lower it down until you feel the piston catch it. There was a guy on here the other day that his pulley mark was not lined up with what was supposed to be TDC and he nearly lost the valve down the cylinder. (don't mean to scare you )

 

the TDC works like a charm but if you can hook up a compressor then that would be better IMO. i found it kinda annoying while putting on a valvespring having the valve drop about an inch so the dang locks wouldnt go on. you have to be real careful not to bump the valve or it drops down.. it was a real PITA. if you had compressed air then it shouldnt drop at all.

 

Wow great idea, I was going to go and buy one of those tools, but this sounds much better, and cheaper to boot!--Thanks for the tip:

 

One way you can check the accuracy of you balancer mark is by pulling the no. 1 plug and sticking your finger in the plughole, rotate the motor by hand and when your finger pops out like the cork from a champagne bottle you are at or about TDC.

 

If your valve guide seals are good the valve will stay up. If you have a dropper, a little bearing grease on the valve stem will help to hold it up.
Here's how I do it. Bring the #1 piston to tdc on compression stoke. Pull the rocker arm, change out the valve spring, reinstall rocker arm and adjust. You can do half of them in this position. Then rotate the crank 360 degrees and do the rest. Done deal, no air required. (Haynes manual has a layout of the sequence)

 

One very important thing with the compressed air method if u have a M6 is to make sure it out of gear!!! I had mine on jack stands in the front, pretty high, hooked the air to it and it almost jumped off the stands, scared the hell out of me. Piston goes down, so the motor turns over when the air is applied,if its in gear its gonna move, double check it!!

 

I use a straw or a piece of plastic tubing in the plug hole and rotate until I feel the piston at fully TDC. Can't make a mistake this way. I have a air fitting but it was to much like changing plugs
. Time consuming.

 

If I do the TDC method. I bring each cylinder up to TDC. That way the valve will not fall. You have to turn the engine over to TDC for each cylinder though.

Before you begin each cylinder.... When you take the keepers off, pull and push the valve up and down slowly to make sure the piston is up. ( Of course find TDC first. And be gentle so you the valve won't slip out of your fingers... just in case you don't really have TDC. If the piston is up... it won't matter whether you drop the valve or not, because the piston will stop it.


Putting something into the plug hole , or using air to hold the valve may be a desireable alternative also, becuase trying to put the keepers on while the valve keeps falling gets annoying.

 

I tried the compressed air method when doing mine, I gave up on that idea after about 5 minutes. I could barely thread the fitting into the #1 plug to start, a lot of the others I can barely reach to do a plug let alone thread that adapter hose into the hole
The only way I could possibly see that working is if you had the headers removed, especially with SLP shorties there was no way it was going to work. I ended up doing the TDC #1 & TDC #6 method, it worked very well.

 

I concur. The compressed air method works great...but easy plug access is the deciding factor. I tried using air once but found the hassle of trying to connected the fitting was 5 times worse than doing a spark plug change on these cars. I recommend the TDC on a LT1 f-body.