What is causing this? Engine has recently be done. I have a new radiator. No steaming or boiling over. I have verified that the over flow is free and clear.
Not enough goo. I used Permatex #2, but had to do one over because I didn't use enough.
You can use Permatex #2 but the more prefered one to use is Permatex #1.
You can also use RTV. The RIGHT STUFF should do the job too.
I have used them all, but prefer Permatex 1. I have never had one leak in all my years.
Rub a little with your finger all the way around the hole. Look in there, make sure there is some all the way around.
Also, use a regular nickel (Buffalo head are best) instead of the freeze plug you buy. You'll save a bit of money and they won't rust.
They sell Brass freeze plugs. Are you using water or an antifreeze?
Gary is right. The buffalo nickel is a beautiful coin, but a bad feature of its design was the raised date. The ones with the date worn off have so little collector value that they're cheaper than new brass freeze plugs.
If you put them in with JB Weld you won't have any leaks ever.
Is that where "It ain't worth a plug nickel." came from?
I'm with Jack,BRASS!!
I've never tried using nickels. About 1o years ago I put steel steel freeze plugs in my engine. Within about a year they failed, rusted through looking just like the one in your first photo. I replaced them with brass plugs and have had no trouble since then. I didn't know the recommended procedure is to goop them up, and I installed them dry. I thoroughly cleaned everything and tapped them in place.
Just my experience.....
I used a nickel out of my pocket. One of the plugs on my 21 rebuild leaked a little so I replaced it. It was a 1970 something as I remember. Worked just fine and I only spent a nickel! If I ever rebuild another T engine it will only cost me 15 cents for freeze plugs. And that's if I happen to have 15 cents in my pocket.
Along with some type of sealant of course.
If the freeze plug counter-bores are re-machined to clean metal in the re-build process they generally will not leak and you don't have to use any sort of sealer. But this usually doesn't get done on a "low cost" rebuild.
Adam is spot on here. Blocks such as the one pictured need the manifold deck surfaced and the core plug (NOT freeze plug) bores deepened. Otherwise, you will be forever dealing with exhaust leaks and water leaks. On a previous thread, Steve kindly posted a pic of this process on my milling machine.
I personally would not use JB Weld use the Permatex or RTV. The reason is; if the block freezes you want the freeze plug to pop out with the expansion of the ice forming. Hence the name: freeze plug.
Kevin is right use the Ultra Black
If the block freezes the plugs may or may not pop out. This will happen about the same time as the water jacket is breaking open. Anti freeze coolant has been in common use for something like 80 years or more, yet new vehicles still have these plugs in block and head castings. This is because their only function is to support the sand core in the casting mold.
I use permatex on the core plugs, and always use brass, or nickels.
Freeze plug is a misnomer, they are really holes to support the internal cores during casting. In myho if your coolant freezes your block will crack.
Erik and Ted are correct. The term "freeze plug" became popular probably back when water cooled gasoline engines were first made. Sometimes when an engine froze the plugs were pushed out, but that was not their main purpose. The term "freeze plug" has endured since then. I learned that over fifty five years ago. Dave
Yep they are core or casting plugs! But I still would not use JB weld to install them! JB Weld is hard to remove and I want something that can be removed if I have to rebuild the engine in the future.
Don't need to freeze to have one blow out! one of my T's is a USA import and it popped one of those nickel plugs going up a hill on me, man that water can come out fast. lucky I had an modern spark plug in my tool box, rapped some electrical tape around the thread and screwed it in the hole, I always carry water with me and that got me home.
I've seen maybe 100 freeze cracked blocks and I don't think I ever saw one of them missing a "freeze plug".