About a month ago I started a thread about having an oil leak around my timing chain tensioner. Long story short the dealership determined it was actually the head leaking through the casting which they said they'd fix under warranty. Then they changed their mind and said my warranty was void so they'd fix it but it would cost $1400! F*** that! Here's the thread if anyone wants to check it out: https://www.cobaltss.net/forums/prob...licies-264772/

So anyway I'm looking into buying a reconditioned head and swapping it myself. Actually taking off the old one and putting on the new is no prob but can anybody tell me the best way to set the timing right so I don't bend all the valves and have to start all over. Any help is appreciated!

 

bump anyone?

 

bump! come on someone has to have some suggestion for me

 

All you do to set the timing is line up the three marks. There's one on each cam gear and one on the oil pump gear or whatever that is down there. You will have to turn the cams in for them to work. Take off the gears then put the gears on the cam once you have them on the chain right. It's pretty straight forward. I'm sure there is a write up somewhere or if you have that 300hp book it shows you in there.

 

I have a copy of the ecotec engine handbook, but all it shows in there is taking the head off when the motor is set to TDC to do a rod and piston swap and then putting that same head back on so as long as the motor is at TDC, the timing will be set right. This makes me wonder if I set the motor to TDC and marked the cam gears and timing chain, would i just be able to put the cam gears on the new cams and rotate them to line up with the marks I made on the timing chain?

 

The timing chain already has 3 marks on it. One for each gear and one for the gear on the oil pump/ crank gear. You don't have to mark it.

 

Do you happen to know which marks on the chain correspond to the which marks on the cam gears? And do I set the engine to TDC and then move the cams or does it matter what position the engine is in?

 

Blue mark is intake cam. Purple is crank gear. I think there's two purple the one clossest to the blue one is for the exhaust cam.

 

Ok thanks. What about the position of the crank? Does it matter if it's in TDC or should I just leave it where it stops when I shut it off?

 

You have to have it in the 5 oclock position. That's where it will be at when the car is at TDC.

 

Ok thanks for the help. I hope this won't be too hard

 

One more question, will I need to pull off the front cover so I can get at the crank gear to line up the timing chain? Or is there some way to keep the chain on the crank gear so that I will only have to worry about the cam gears?