CJAA Piston/Valve Inspection guide??

[Kaija]

I had the dreaded timing belt break on my 2013 Sportwagen CJAA engine a while ago, and am finally getting a chance to really dig in. I wonder if anyone has a good step by step guide on what/how to inspect the damage.

I replaced the belt in July '22, then used the car as normal for 6 months before it broke.

 

[lemoncurd]

how did it break so early?
how many miles did you put on it?
where you leaking oil on it?
did the drive belt snap and get wrapped up into it?
so many questions..

generally inspecting damage is the same across all engines. take the head off, and look for witness marks. there is a nonzero chance you got lucky and didnt get any piston to valve contact but its slim to none. if you see any witness marks youre looking at a total rebuild, atleast a top end rebuild + bottom end inspection.

it may be more worth your time to just buy a working used engine off ebay, do the preventative maintenance to it when installing, then keep cruising.

 

[oilhammer]

You'll be better off buying a good used engine, and replacing it. And if you are uncertain of what you did wrong, have someone who knows these engines help you replace that belt so it doesn't happen again.

 

[greengeeker]

What he ^ said, x2

The long story short - there is no reasonable way to inspect for camshaft lobe slippage (they're pressed onto the camshaft tube) so you more or less need to replace them blindly, at significant expense. Combine that with the rest of the cost of the head rebuild, head R&R and you've exceeded the cost of a good used engine.