Coolant Plug Leak On Dart Head Help
Coolant Plug Leak On Dart Head Help I have a small coolant leak coming from the plug toward the back, passenger side, of my newly installed Dart head. It is the plug that came off the original head. I noticed that the plug seemed to sit flush against the original head when installed. But on the Dart head, it has about 1/4" of space between the head surface and the head of the plug, after tightening. I called Dart and they said it should be OK that way because its a pipe thread (tapered). I took the plug out, put a load of thread sealant (ARP) back on it and tightened it as much as I could, it still leaks. I was thinking of getting a brass plug to try. Anyone have any other ideas? Does anyone know the thread size and pitch for that plug? Thanks 
Last edited by JoeMack; May 21, 2006 at 10:56 AM.
I don't know what ARP is, but I used the hi temp thread sealant that looks like liquid teflon. On my Dart heads, the plug didn't go in as far as my stock heads. You could order a new plug from GM and try that. Did you clean the plug good of old sealant?
Mine was the same way, the temp sensor screwed all the way in but the stock plug out of my 98 heads (whech went all the way in the stock head) sticks out like 1/4" or so. I just used silicone and it hasnt leaked at all..
Found out that the thread is an M12x1.5 (not pipe thread). Don't think they make that in a brass plug. I'm going to try an O-ring and some silicone on the original plug. Thanks for the help.
