So I have talked to many mechanics at various dealers and private shops and nobody can give me a good answer to why my overflow tank on my radiator is overflowing. Here is the story, about a month ago I drove my 70 Jav with a 360 (slightly built) to my brothers shop 15 miles away. It was a nice night so I was driving a bit harder then normal just having fun with my car. When I got there my overflow tank was spraying out the overflow hole. I have stared with simple repairs and gone up, I have replaced the line to the overflow tank and cleaned it to make sure it is not blocked and has a tight connection to the radiator. I have replaced my rad. cap, I have taken out the thermostat. I have done multiple pressure tests on the rad. to see if it builds pressure and it does not. I do not have any white smoke or coolant in my oil. I have driven it up to 80 miles with out getting on it and the level in my overflow tank does not change but, I can take it out when it is cold and drive it hard for 2 miles (a few hard starts off the line) and it will be overflowing before I can get the hood open. I was just told to put a 15lb cap in the radiator since it is not a stock motor it may need a higher pressure cap. I have been told it was the head gasket or cracked head, but since it does not build pressure when I drive it without getting on it that does not seem like the problem either. Could I be looking at some kind of vacuum leak? Any help would be great. I don't want to pull my heads if I don't have to. Keith Evenson -------------- next part -------------- An HTML attachment was scrubbed... URL: http://splatter.wps.com/pipermail/amc-list/attachments/20081028/10ba82ad/attachment.htm _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://splatter.wps.com/cgi-bin/mailman/listinfo/amc-list