200ci Is this cylinder head ok to run? (cracked valve guide boss)

[mob]

Hello, I recently acquired a 66 Mustang that has been sitting since 1994, it's a 200ci. I took the cylinder head off and disassembled it to replace valve springs. I went to sand blast the head today and noticed this crack on the valve guide boss. I am looking for opinions on if I need to take this to a machine shop to be repaired or if I can run it as is, I plan to use the metal body valve stem seals. I have been asking around and have gotten response saying it's just cosmetic and others saying I should get it repaired to be safe. From what I can tell it looks like new valve guides were installed and maybe at that time it cracked? Some people say it's common. So maybe it's already been run like this, not sure.

This car is not turning into a daily driver, I just want to get it running but long term I plan to swap this motor with something else so I do not have much interest in spending money on it and prefer to just run it if it's relatively safe. Thanks

 

[frozenrabbit]

Looks like a really bad valve guide job. Never seen or had any guide install with tack welds.... Are all of them tack welded?

I wouldn't trust that head in the least. I think you could find an entire engine for a reasonable price, or just a later year large log head on FB marketplace.

 

[B RON CO]

Hi, For the amount of $$$ it will cost to rebuild that head, I would look for another one. You can learn about the different heads available in the tech section and come up with a plan. Good luck

 

[The Beast]

Could you try ot make a steel sleeve and press on the cracked boss. Check and make sure no interference with springs. Good luck!

 

[Frank]

Not advice, just FYI-
Have a 300 which had the #12 valve guide boss split apart worse than that one. JB Weld, 13 years and 100k miles, still in service as a daily driver. Using an umbrella oil seal in conjunction with the factory stem seal.

 

[mob]

Not advice, just FYI-
Have a 300 which had the #12 valve guide boss split apart worse than that one. JB Weld, 13 years and 100k miles, still in service as a daily driver. Using an umbrella oil seal in conjunction with the factory stem seal.

Thanks, I keep having people tell me that this is what happens when you install new guides, installed poorly or by an amateur, but apparently it's not uncommon. Plus this was probably done back some time in the 90's by who knows who. I'm still leaning towards running it. I think I'll just take it to a local machine shop and see what they say.

 

[mob]

Looks like a really bad valve guide job. Never seen or had any guide install with tack welds.... Are all of them tack welded?

I wouldn't trust that head in the least. I think you could find an entire engine for a reasonable price, or just a later year large log head on FB marketplace.

You think they're that bad? I know it's not a good valve guide job but they cant be junk. They aren't tack welded, I think you're just seeing some residue that dried up there. Below is what they look like cleaned up. I can tell these heads have been gone through but it would have been sometime pre 1994. It has thread inserts in 3 of the exhaust manifold bolts, but they are done well and I had no issue removing all the exhaust manifold bolts. I also had someone tell me it looked like they installed hardened valve seats, but I don't know. I've had many people tell me the crack is just cosmetic.

I have also not had any luck sourcing a replacement head in my area, I've been looking for a couple months on FB. I really just don't want to put anymore money into it, I've already spent about $400 to get this engine put back together and anymore than that I am in replacement engine territory, actually I think I'm already over it but swapping an engine for me right now is not ideal.

This is the valve that has the crack: