Noisy tapping sound on 4AGE after rebuild

[ChezzaV8]

Hi,

This is my first attempt at a rebuild after I had a bottom end failure on a track day at Donington. I've rebuilt it, it seems to be running okay apart from this annoying tapping noise. Above 3000rpm it gets quite loud, and then is particularly loud on overrun. I've checked all the valve clearances and they are fine. I think the timing is okay, the compression is okay and it seems to run okay. There's a high probably that I've put some of the valve springs in upside down as I didn't realise there was a right way up.

The engine is a small port 4AGE out of a toyota corolla.

Has anyone got any ideas?

Here's a vid of the noise:

https://www.youtube.com/watch?v=UYv0qfhJ1Ho

[ChezzaV8]

I think it's something in the bottom end. I checked the valve timing and its all okay. I also checked the valve drop at TDC and there's plenty of clearance.

I think it's the rod bush. I'll have to take it out and remeasure the big end clearances and check the rod bushes. Will also check the rings and skirts for piston slap.

[ChezzaV8]

I've got to the bottom of the issue. It's contact between the pistons and head. The squish clearance is too small so at higher rpm the extension of the rod is causing the contact. Time for a thicker gasket.