u/ZebraTypical

Cylinder head cracked or no?

Cylinder head cracked or no?

Hey everyone,

I was hoping to get some opinions from those with experience rebuilding heads.

I took my Z3M Roadster out of storage after about 6 months, installed a fresh battery, and the engine hydro-locked on startup. I pulled the spark plugs and found cylinder #3 full of coolant.

I removed the cylinder head and sent it to a machine shop. They pressure-tested it, resurfaced the deck, and hot-tank/power washed it. They charged about $500 CAD and told me the head passed the pressure test.

After getting the head home and inspecting it closely, I noticed a line between the intake and exhaust valves on cylinder #3 that looks very much like a crack.

Before I assume the worst, I'd like some experienced opinions.

  • Has anyone seen marks like this that turned out to be normal casting marks?
  • Or does this look like a genuine crack between the valves?
  • Is it possible for a head to pass a pressure test yet still have a crack like this?

I'm planning on getting some dye/developer tomorrow, just curious what you guys think?

https://preview.redd.it/zb975i0hchbh1.jpg?width=4032&format=pjpg&auto=webp&s=0c5c2e6bd4b2e460275263dc0ff119cb21c36678

UPDATE:

https://preview.redd.it/g787elw70nbh1.jpg?width=3024&format=pjpg&auto=webp&s=c9c122af59b70c048007ea525f73bddb6d745ca8

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u/ZebraTypical — 1 day ago