I went over to NAPA today for a helicoil kit and I was talking to the guy working there about the crack I have between the exhaust port and the water jacket in the head. He told me about this stuff that can seal cracks in the block, heads, head gaskets, and radiator. It is called K&W Permanent Metallic Block Seal. Do you guys think this will work? Has anyone used this stuff before? I am going to do some reseach on this stuff and maybe give it a try in a few days. I just hope it doesn't clog up my new radiator.

i used it in an 83 wagon. it held up for a little bit until i flogged ot out in a farmer's field. re'popped its head gasket.

 

it worked in an spfi dl, held up about a couple of weeks but then let go(head gasket)

 

its ot a permanent fix, but it works.

 

flush out your system with straight water, and run straight water(you dont want coolant eating your bearings)

 

the instructions all for staight water, run for like 15 minutes.

 

keep running staright water, you can run antifreeze, but i only reccomend green in cold seasons

You might try JB weld, seriously. I'm not sure if it can take the temps that it would be exposed to though. But that is what is holding a large chunk of the crankcase on in my outboard motor, and my uncle used it to fix a cracked block in his classic firetruck. I also have JB weld on my exhaust near and on the cat, and it seems to be holding up there.