No compression after overheating

[xxboulavardxx]

Well if the piston is at TDC then you have a mechanical timing problem. Now without the model and type I don't if this had the plastic camshaft or not. IF it the one I suspect then the cam lobe section has slipped on the camshaft. Now it does depends which TDC you are on too. Normally the exhaust only opens from BDC to TDC on the exhaust stroke. It also opens slight and close right before TDC compression stroke as most of these engine do have automatic compression release to slightly lower cranking compression.

For the compression gauge you do need one for small engines as compression gauges for larger engines are not accurate at low volumes.

Thanks for the pointers, a lot of good info. The compression gauge I have ranges from 0-300
psi. The engine model number is 128T02. I didn’t take a look at the camshaft but I looked up the original part (691449) and I think it’s metal. This is the first time I’ve taken it apart so I’m learning as I go