Engine Maintenance pre goblin

[Friedhouse]

Drove about 450 miles last weekend to check out this 2007 SS/SC w/160k mi. When choosing a donor I wanted to ensure I had a mechanically decent car at a decent price, as I didn't want to dive into the engine. Well the interior and exterior are pretty much POS status, but I felt like the car ran very smooth. Only maintenance work this owner had done was a used transmission swap w/ 70k miles, a new clutch, and aem fuel pump. Didn't have any history from the previous owner he bought the car from @140k miles. I bought it for $2800, and drove it home 450 miles with no issues. Ran smooth.

My question to everyone now though is what preventative maintenance should I get done while the engine is out? I don't hear any timing chain rattle and I would think the chain would have been replaced at some point by now, but do I just do it anyways?

 

[Ross]

Replace the timing chain guide bolt with a Dorman bolt.
If your timing chain tensioner has a flat top, replace it with a tensioner with the new design, bump top.
Up to you if you want to do the timing chain, but a broken chain guide bolt is a good indication that the chain is stretched, and needs replacing.

 

[Friedhouse]

Replace the timing chain guide bolt with a Dorman bolt.
If your timing chain tensioner has a flat top, replace it with a tensioner with the new design, bump top.
Up to you if you want to do the timing chain.

Thank you Ross!

 

[Ross]

I learned a week ago that if the Cobalt timing chain guide bolt is broken, it is a strong indicator that the timing chain needs replacing.
Apparently when the chain starts getting loose from wear, it starts slapping the timing chain guides, and can lead to a broken bolt.

 

[r3drckt]

Mine broke and the resulting loose bolt head carved a hole in the cylinder head wall next to it. Car still ran fan thankfully. Definitely replace the 2 bolts that Ross suggested. It'll save you a lot of hassle later on if another tear down is needed.