Cracks on the outside of cylinder head (1 Viewer)

[aclos3]

Looking at the passenger side, just above the exhaust manifold. These cracks looks wicked. I have it pulled apart to replace the original radiator, oil pump seal, alternator, fuel injector service, power steering cooler, etc. Is my head on its last legs? To my knowledge, the HG is original at 235k miles. Thank you!!

 

[NorCalFJ100]

Wow. Doesn't look like it's leaking oil! But that doesn't look good at all. I have an almost invisible hairline crack that leaks out oil when the engine warms up.

 

[1911garand]

I believe the "cracks" are normal and from the casting process..not really cracks at all. Please correct me if I'm wrong.

 

[aclos3]

I agree with you both. They look horrible, but nothing seems to be leaking through them. Hoping they're casting cracks and superficial, but don't want to neglect it if it is a genuine problem.

 

[ferg]

Are they actually cracks? Looks like casting flash to me.

 

[maxamillion2345]

Casting. 100% normal

 

[NorCalFJ100]

@aclos3 as long as they don't leak oil, I'm sure you're fine!

 

[aclos3]

Thanks for the sanity check everyone. Here's where I am with the big work list. Still in tear down mode, but tons of parts are about to start going in.

 

[aclos3]

 

[aclos3]

 

[Rifleman]

If you do a search, you'll find that these cylinder heads can, and do crack. Most of the photos I've seen the cracks develop in, and below the valve cover gasket mating rail. Once it cracks you'll start to notice oil seeping out where the crack is located.

 

[NorCalFJ100]

@Rifleman that's exactly what happened to me...3k miles after a brand new rebuilt motor and head (which was also pressure tested.)