The first pic is more for reference. You can sort of see the pit on the number 2 cylinder coolant passage. The second pic shows a bit more detail but still, it's hard to capture a 3 dimensional problem and relate texture, etc on film.

It's an irregular shaped pit a few millimeters deep, several millimeters in diameter and has rough, sharp edges. There is good flat (machined) metal between the passage and the cylinder.

I'm worried about the sharp edges though and gasket tearing. Also, I'm wondering if the shortened surface for sealing will be an issue. Am I probably safe or is there a cure I should pursue?

This existed before machining and believe it or not, it was the only cylinder that wasn't burning water! After machining and learning that the head was slightly bowed/warped, I figure the bowing was probably the cause of gasket failure after only 30,000 km.

PS: As for checking for internal cracks...any suggestions? I'm thinking of running varsol through the coolant ports till they're full and checking for seeps.

 

Ah crap, hang on a second. Pic's were too big

 

Ok. 2nd try

 

Just be careful. Those fail because of the erosion by the water jackets. As long as the pit isn't into the firing ring on the h/g you should be ok

 

If by "firing ring" you mean the steel reinforcement ring around each cylinder on the gasket, yes it is. It lays right over the pit. In fact, I think All that nice flat area in my picture is inside the cutout. The thing that's really strange is there were no leaks in that cylinder - the pit was there albeit it wasn't as wide. It has nice and clean piston head - the only one without pinkish white valves!

S*** I should have seen this coming before machining it. Now I'm nervous because I don't want to do this job again. Truck has been out of commission for over half a month while I've been chipping away at it as time allows. I can get a used head for 200 bucks but it hasn't been machined. I better start researching prices.

 

Yep. If its at the firing ring and you put it together, you will be doing it again and soon. Find a good used head. Ask machine shops. Sometimes they have them ready to go for sale

 

Well I'm seeing brand new ones for 150 -250 plus shipping. Local shops are quoting 400. Guessing I'll be hangin out for a while longer

Just quit smoking 4 days ago too! Ah today is going to be a rollercoaster. But thanks bro Better to be smart than sorry.

 

Good luck with it!

 

a good machine shop can weld that area up and mill it back down.

 

as small as that area is I wouldn't trust that no matter how good they were. Save your money and buy another head