Rusted freeze plugs.

[JDaniel64]

Hey everyone, new to the forum. I have a 1952 meadowbrook that has been in my family for 25 years, and just the other day while letting it warm up, one of the freeze plugs failed and left a giant puddle of coolant on the garage floor. It was one of the large stamped steel plugs towards the rear of the block. It looks to have failed due to corrosion. I was just wondering how to go about replacing it and possibly if the others need replacing as well. Thanks.

[Grdpa's 50 Dodge]

Think you pry out the old one best you can, probably clean as much gunk out as you can and pop another in its place,,,if only it was THAT easy.  I think they use a dab of sealant on them but hoping better wrench heads follow with better advice.

[Don Coatney]

Use a self tapping sheet medal screw to remove the old one. Surgically (or as best you can) clean the hole. Use a good sealent such as is pictured all around the outside edges. Slip the replacement into the hole and using a ball pien hammer dimple the center of the replacement to expand it and lock it into place. Replacement plugs are 1 5/8" and can be found at most any good auto parts store. Brass is better if you can find them.

 

 

 

 

 

[Grdpa's 50 Dodge]

by ball peen hammer me thinks Don means put round end on frost plug tight,,,hit with a bigger hammer a good rap to dimple plug and expand it

[Don Coatney]

by ball peen hammer me thinks Don means put round end on frost plug tight,,,hit with a bigger hammer a good rap to dimple plug and expand it

If your aim is bad

[JDaniel64]

Thanks for the responses Very helpful, especially the visual tutorial, very nice. Would have taken me a LOT longer on my own. Lol, wish I could get it as flat/perfect as Chrysler did from the factory, but we'll see.

[Andydodge]

Be VERY careful hitting one hammer against another as either one could shatter, at least wear goggles.......what I do is use an old coach bolt or some other steel or brass drift of about 1/2 to 3/4" round and hold it against the plug........I use a large headed hammer, ie, like a mallet or similar and usually you only need one good wack........Dons right re the brass plugs, its worth finding them as they will never rust.......also if you need to do one check the other 4 and if they are all about the same appearance and age its worth getting into them as well........with any or all out cover the dissy and give the water passage a good hose out...ain't cars fun!......lol..........andyd

[54Illinois]

My dad taught me to use a 1-1/4 socket to set the plug.  Or was it 1-1/2?

[Ricky Luke]

And replace them all....

 

Rick

[captden29]

dorman makes a metal expansion plug that installs with a wrench[ 7/8 I think],part # 568 010. I installed them 2 years ago on my flathead.they can be left in permanently. very easy installation, no need to swing hammers.about $5.00 each. capt den

[Plymouthy Adams]

installing the Dorman unit is not just bolt in and forget..the Dorman stock 1 5/8 size is rather thick rubber seal..actually made for the thicker casting plug of the later V8 type application that is not a step cut hole...you may find that the plug will acutally hit the cylinder inside the jacket and prevent proper seating....over tightening this style will also prevent it from popping out should for some reason one get caught up without antifreeze and the ice starts forming...use caution here...you may also find that the Dorman 1 1/2"  unit be the better fits....

Edited December 11, 2013 by Plymouthy Adams

[Don Coatney]

I would not recomend the screw in  expansion plugs. If they were meant to be perminent I would think the factory would have installed them.

[Dave72dt]

They're mistakenly and commonly called "freeze plugs"  but don't bet on them popping out and saving a block.  They're core plugs designed for getting the core sand out after casting.

[Plymouthy Adams]

that is true Dave...I have seen frozen cracked blocks with all plugs securely in place...they are not guaranteed to pop out....but as a side benefit to the casting process you may get a bit more protection..were they over dimpled? do brass ones pop out easier than steel ones?   As Dave points out..don't bet the farm on these popping out...ensure you have adequate protection level with your coolant..

[Dodgeb4ya]

I use a heavy large flat steel driver to install the Mopar flathead soft plugs so as to make them look flat and kinda factory looking.

Some more visual soft plug info....

Bob

[JDaniel64]

I looked at the dorman expansion/compression plugs, they would be handy, especially since the plug that popped was right behind the oil filter canister. Anyways, the 1-5/8 would be too large regardless since the opening tapers to about ~1", also I agree that they seem more temporary than permanent. Thanks for the info that they are 'core plugs', would not have guessed and neither would the parts stores that I visited, but nevertheless I found the correct plug! I found the old plug that popped out laying in the corner of my garage, and it did not fail due to rust as I had thought but simply dislodged from the engine. It is not an original plug but a very old replacement that was poorly installed (some small chisel marks, had pipe dope around the edge), and was in fairly good shape with a neat design on the back. Will attempt to replace it next week when the temp. rises past 50F, too cold now to be smashing fingers :S Thanks for the replies so far!

[captden29]

the dorman plug I referred to has no rubber or plastic parts. it is steel and copper plated steel. it has a blowout pressure resistance to 300 psi.i do not think the factory had these available when our cars were built. even so, the standard core plug is cheaper and easier to install when the engine is out of the car.the dorman core plug can be used as a permanent installation, but certainly keeping one in the glovebox is a good idea for a quick easy roadside repair. capt den

[bamfordsgarage]

...keeping one in the glovebox is a good idea for a quick easy roadside repair...

 

Smart suggestion. I'll put one in my road-trip toolbox this week. Thanks!

[48ply1stcar]

I used the expansion plugs because the engine was in the car and I couldn't get a hammer on it.  That was in 1995 when I started my project.  Never a leak, never a problem.  In fact I can walk over to that engine on the floor and it's still there.

[Plymouthy Adams]

so you are saying...the freeze plug help up but the engine somehow fell out....

[48ply1stcar]

That's close to what happened.

[JDaniel64]

Today was nice enough to change the plug finally. Here are some pictures of the old plug (right) and the new plug (left).

After I cleaned all the old crud off the old core plug I saw that it most likely wasn't original, and that the indentation necessary to completely seal/lock the plug in place seemed insufficient (almost looks like a toothed masonry chisel was used). 

Here is the uncleaned opening for the old plug right behind the oil filter. (Please forgive the dirty engine)

And here it is after cleaning with #0000 steel wool and isopropyl alcohol.

Now the pipe dope, a little messy but wiped some away after the picture was taken. 

New plug popped in!!! Started with a 1-1/2 ratchet socket to seat it but come to find out that was too big (was thinking that since the plug was 1-5/8 that a 1-1/2 ratchet socket would seat it, right? Nope, the INSIDE diameter is 1-1/2 but the outside diameter is not, it's over 1-5/8, duh...), so used a 1-1/8 and after a few whacks with a hammer it was in. 

Pipe dope cleaned off.

Now here is where it got interesting, indenting the plug to seal/secure it. Hammer-on-hammer was a no-go, not enough room behind the oil filter. What I settled on was a ~8" x 1/2" piece of rebar and a sledge hammer (using the side), a few hits and misses later I got the amount of dent-age I was looking for. It has held for over 3 hours, both idling and driving with no leaks, so I think it is a mission success!! Thank you guys for the responses, you made a depressing problem into a pretty easy repair! 

Edited December 17, 2013 by JDaniel64

[desoto1939]

I did a search on Dorman Products and the 1 5/8 cooper expansion quick seal copper plug is part number 568-010.1

specifications  1 5/8  maximum expansion 1.655

 

 

[fstfish66]

ive seen the dorman expandables used in the early hemi and poly motors,  i currenty have one in an early hemi,,,no problems so far,,i have seen guys spread JB weld on the expandables and  standard freeze plugs i guess to prevent them from leaking or poppng out,,,just my .02

[mayflower48]

I made my freeze plugs out of  stainless steel and used O-rings.  I would add a photo but have spent an hour and a half trying to figure out how with no luck.  Used the search with no luck.