Posted by Matt Wilson [172.69.69.25] on Saturday, July 07, 2018 at 22:17:06 :
In Reply to: freeze plug popped again posted by scott56 [172.69.22.239] on Saturday, July 07, 2018 at 19:57:27 :
It looks like you used something fairly narrow to put the dimple in it. I haven't done very many of these (about one engine's worth), so take what I say for what it's worth, but it seems like you should use something wider, as Kaegi says. I agree it should be almost as wide as the plug/hole. I have used the flat face of a ball peen hammer (the side opposite the ball), placing it up against the plug and then rapping the ball side of it firmly with another hammer. This should flatten out the plug and spread out its edges nicely to make a good seal. The diameter of the flattened area should be pretty sizable, probably half the diameter of the plug, or more. Sealant is recommended too. I don't recall what kind I used, but others here will have suggestions, and you can search Phil's Archives.
I had a bad experience with a plug popping out while I was going down the road, and didn't realize it, and almost burned up an engine. When I looked at the rest of the plugs, I found that the dimple was barely visible. The machine shop had installed the plugs and I didn't notice how poorly they were installed as I assembled the engine. I ended up replacing all the plugs, including those under the timing cover and those on the back of the engine. For the ones on the left side, I installed the type with the compressible rubber, with the stud in the middle, like the Dodge Boys talked about. They seemed to work fine.