Hi,
Just bought his hhr which actually ran pretty smoothly after a hard start and coding P0016.
So I knew it needed a timing chain that I am in the process of replacing as I outlined in another thread - that had it's own issues.

But, I have seen differing opinions on this. Some say don't mess with it because it will cause issues down the line from chunks you don't remove. Others suggest taking a wire brush to it and cleaning as much as you can.

I only hesitate because that car would run very smooth but the amount of sludge this cat has on the top end concerns me.

Your suggestions are appreciated.

Thanks

 

Wire brushes shed bristles, a loose piece of steel floating around is more dangerous that a loose bit of sludge. I'm not saying to not clean it, I'm saying don't use a wire brush.

 

Old timey cure would be a quart of diesel in the oil far several hours running. Or, Sea Foam, Lucas oil etc. Read the labels, they are really diesel/aviation fuel.

 

Another old time treatment is Marvel’s mystery oil.

 

And change the filter often during the process

 

It looks excessively dirty, it needs to be washed. The upsetting thing is that this dirt is probably in the depths too. You won't come there with a rag - you need chemistry.
Flushing of the oil system, chemicals from carbon deposits on valves, etc.
And yes - a good filter

 

Should I clean some of the excess with a rag while I have the cover off?

 

Would not hurt.

 

Soak a rag in gasoline, or white spirit, or alcohol, or brake fluid ... anything that can dissolve fats except Ferry.
And then a slow, progressive wiping of deposits.

 

Here's what you need to be concerned with, If you get pieces of gunk and or cleaning material such as scotch brite or pieces of metal brush and even one of these gets through and into an oil gallery you will spin a bearing.
That really isn't that bad. I would leave it alone.