i have a freeze plug seeping on the driver side of my 390 not a lot but enough so you can smell the coolent when it drips on my y pipe. How do ya replace these things? ( i hope its not from the inside )

thanks for any info !!

 

First you need to drain the coolant. There are pipe plugs in both sides of the block on the same line as the expansion plugs, close to the tranny end. Remove both of these to drain the block. If you don't have any coolant come out when you remove them, stick a screwdriver in the hole and scrape around, coolant will follow.

Next, if you are lucky you won't have to do the one behind the motor mount. Find the leak in the plug, usually on the bottom edge, and punch a hole through the plug. If you actually have a hole through the plug, slip a pry tool through and pry the plug from behind. If you have actually driven the plug onto the water jacket, put a vise-grips or pliers on it and start yanking-twisting-prying. You'll mangle the plug before anything happens to the block. If the plug is really corroded, the flat part will disintegrate and you'll have the sealing lip still stuck in the block-it's gotta come out.

After you remove all traces of the old plug, clean the sealing surface of the block. It should be clean and dry before you install the new plug. Apply your sealer of choice to the outside lip of the plug. Use the biggest socket you can fit inside the plug to hold-position-drive the new plug in place. If you can use the words finesse and hammer in the same sentence, GENTLY drive the new plug in by tapping on the socket. When the lip of the plug is even with the outside of the block, you are ready to put everything back together and check for leaks. My preference is to install drain-***** instead of the pipe plugs and clean/flush the cooling system before adding anti-freeze.

Good luck, Mike

 

Hypoid, thanks man that is what i wanted to hear. can i pick up a plug at any parts store ? Napa ect.

 

Yeah, they are pretty common. I have heard some people mention something about a slightly different sized plug. Ford used some odd fraction size, seems some suppliers rounded to a slightly different size that is more common. That's just off the top of my head, haven't done any plugs this century.LOL

 

I have one on my passenger side I plan on doing soon. I was just wondering what everyone reccomends.

I hear alot about brass is this the best?

I also noticed Napa sells Stainless Steel. I am a firm believer in stainless what do you guys think?

jd

 

I have used brass for some time and never had a problem. Stainless would last a long time, but it can be a bear to work with(hard). Might be tough to install.

I think 1 3/4" is the size in most books and kits, but actually they should be 1 49/64", they seal better.