repairing broken corner from head

[inmyshadow]

I was doing thread repair today on the back of the head on the timing belt side. I was chasing the threads. The corner broke off.

Can the head be saved? I wasn't in the mood for this. This is my good head that was rebuilt a few years ago with very little mileage.

[turbovanman²]

Pics?

[inmyshadow]

No Pictures. Head is still stuck on the motor. The corner is broken off at the bolt hole. I can see the what is left of the theards. Goes down the side of the head until is mets the block.

So far, just idling the car it isn't a problem. I sure it will piss out oil whenever I drive it.

I'm planning a short block rebuild. Just wondering if its safe to have the corner of the head welded for a new bolt hole. Not it the mood for chasing down more good heads for rebuild.

later

Pics?

[MiniMopar]

The entire corner of the head cracked off? Well if it doesn't intersect any thing important like a coolant passage or anything, I'd just clean it up real good, JB Weld it back on, and carefully redrill and rechase the threads.

[4 l-bodies]

The head probably was cracked from hydrolocking it from silicone. Seen that about 25 times over the years. Might also have happened if you bottomed out the tap and kept turning. I always chase threads every time when using any 2 piece valve cover gaskets due to this issue. They never crack into anything critical, but the correct fix is to weld it and retap, helicoil, or time sert. JB weld might buy you some time though, but it's a band-aid fix.
Todd Nelson

[inmyshadow]

I don't use silicone to seal my valve cover. Using a one-piece valve cover gasket ensures that. I sprayed carb cleaner in there before I started. But I let it sit for about 1/4hr before I tried the repair the threads.

That hole had been heli-coiled before. I'm thinking as I chased the threads, it actually compressed the heli-coil. Then breaking off the corner.

Once I get this motor pulled, I'll see if the machine shop can weld that corner up enough to put some threads in there.

It just bothers me because it is one more thing I have to fix this summer on the car. I haven't been able to enjoy the car since 2006. But, this is why I have the beater neon for. Just tired of driving that slow POS.

later

The head probably was cracked from hydrolocking it from silicone. Seen that about 25 times over the years. Might also have happened if you bottomed out the tap and kept turning. I always chase threads every time when using any 2 piece valve cover gaskets due to this issue. They never crack into anything critical, but the correct fix is to weld it and retap, helicoil, or time sert. JB weld might buy you some time though, but it's a band-aid fix.
Todd Nelson