I have rotated my crankshaft without the chain more than 4 full turns with no damage. That was a 2008 2.2L, no VVT.

 

Some links


https://www.google.ca/search?q=ecote...&client=safari

 

Looking through those cobalt forums, it seems like the timing chain breaking is a common problem. Some of those guys got lucky with the ticking noise. The only warning I had was the CEL and then poof... broke engine.

 

I've been trying to rack my brain about why my timing chain might have broken. I'm taking it back to the shop this week and the mechanic is gonna tear into the motor to see if thats really the problem, but when I first talked to him he mentioned that not changing the oil regularly is a pretty common cause for this type of problem. I have a feeling he is a stickler for changing the oil every 3k miles and my dad said the same thing to me, but I have always gone off the DIC and usually change it when it gets down to 30%. I've researched and it seems like a lot of other HHR owners go off the DIC too and they change their oil around 30% as well. Could going that long between oil changes really have caused my timing chain to break?

 

Only counts if you are an oil salesman.
Chains break, usually because a guide breaks. The guides are nylon/plastic, having a piece of metal running at high speed on them for millions of yards wears them out.

 

Yes and no.

Not changing oil regularly will cause engine parts(including timing chains and guides) to wear prematurely.

If you use the recommended oil, 5w-30 synthetic meeting GM Standard GM6094M, and change at 30%, you should have no problem at 78,000 miles. Unless it takes over a year to get to 30%, then that would be risky(you should change your oil once a year minimum).

Have the mechanic pull the valve cover and show you, if it's broken. Then you won't feel like you're being scammed. In his defense, just because he didn't have it very long, doesn't mean he didn't do a proper diagnosis. It would not take long at all to pull the valve cover. Or he may have done a compression test and determined that the valves weren't closing. Ask him what test made the diagnosis.

 

It's not the oil change intervals, it's just life!

 

Well that's good. I was gonna be pretty upset with myself if I ended up doing the damage by doing the wrong maintenance. Guess it was just "bad timing".... hahaha.

 

Just to compare, on my 06 2.2 I went off the DIC and usually had around 7300 miles at 5% and changed with M1. I did that starting at 5K miles. At 117K miles, no issues.

But, I remember back a few years ago there was a new part for the cam guide that had an extra oiling hole. I did make that swap as they said it would provide better oiling for the chain. Whether that made a difference or not, no clue.

 

Yes the new style timing chain tensioner

https://www.amazon.ca/ACDelco-126085.../dp/B0049Z8JNC

New on the left old on the right