I just installed a set of ported ls6 heads and everything thing went quite smooth. After the car got to operating temp. I noticed a little puff of smoke coming from the driver side header every now and then. Well I took a closer look and it seems that coolant is leaking from the header bolt hole. So I removed the two center header bolts where it looked like the leak was coming from and when I pulled the bolt toward the front of the car out coolant poured out of the bolt hole. This is not my first head swap but I have never seen this. Has anyone else seen this before and yes I will be calling the sponsor that I bought the heads from tomorrow.

 

Mine did the same thing! But with alittle sealer i fixer her up. Talke to gunner and he said there is a very fine line between the header bolt and the water area. But i did not want to take the heads off so us a small ball of two part epoxie and put it on the end ot the header bolt and used sealer on the the threads. The leak is fixed now, but it was just to Wierd.

 

It happens. I personally havent ever had a problem with that happening, but Ive seen maybe 2 other cars that did. Like blkvett mentioned, just take some epoxy (JB weld, etc) put it on the end of the bolt, then use thread sealer on the threads then re install. Give it time to dry and you should be good to go.

 

i am having a similar problem. however, i don't understand why you would put jb weld on your bolt. i want to be able to get the bolt back out.

 

I have seen it on many small blocks. some of the bolt hole lead into coolant jackets. Not sure if an LS1 is supposed to be that way but I have seen it many times. Use some blue locktite and it will seal up fine.