MGB MGB Cracked Cylinder Heads Question

[Deleted member 8566]

Hey everyone,

Right now I have a post in the WTB section trying to find a crack free cylinder head. Although something has been recently brought to my attention by two separate people and I wanted to get a confirmation before I made any decisions. I would appreciate any help and advice.

So I have taken 7 cylinder heads to a local machine shop to be checked for cracks. According to the shop, ALL of them are cracked somewhere or another. We all know MGB cylinder heads are prone to cracking and notorious for doing so. However, what I have been told is that at least 1 or 2 of the cracks are surface and not near where the cylinder meets up, the valve seat area or spark plug area, basically just a crack somewhere in the top casting near nothing significant.

I haven't seen the severity of all of them in person, just the initial 2 I dropped off. I am going to pick up the rest in a couple hours.

The shop these heads are at does not do welding repairs to cylinder heads either. Also, they don't specialize in British/European car heads (I'm in San Antonio, almost no one does, not sure if that makes any type of difference)

My questions are first, if the cylinder head has a surface crack near nothing significant, if it still usable (without repair), second, I know one of the heads cannot be repaired for cracks but the other 6 may be able to be repaired by a different shop, and if that is the case, what should those type of repairs cost?

Also is there any other information I need to know?

I know it is hard to give feedback without seeing them and until I go grab them I know it's still a bit of a guessing game, but I do appreciate any help that can be offered.

Best regards,

Justin

 

[bobhustead]

I was an MG line mechanic for a couple years after I got out of college in 71, and there are guys on this forum with a lot more knowledge, but, I did not know of a propensity for cracking. Hard to imagine that all these heads are cracked. Go to another machine shop. Bob

 

[Marvin Gruber]

I have a stack of cracked MGB heads. Most are cracked ( later heads) on the outside by the #2 sparkplug and head bolt. They weep fluid but could still be run. I've seen several that were welded, some worked some didn't. The early heads seem to crack between valves. Those, I've been told are easier to repair.

Marv

 

[David_DuBois]

For crack repair in non critical areas, you can use a process called stitching. Basically you drill and tap a hole at one end or the other of the crack. Screw in a bolt with locktite and then cut the bolt off flush with the surface. You then drill and tap another hole half way in the first bolt and put another bolt in with locktite, cut off flush and continue to the other end of the crack. I had that done on a head with a crack in it and it is still in use. For more information on this process go to: https://www.locknstitch.com/
Cheers,

 

[blueosprey90]

https://www.flowspeed.com/cracked.htm