Freeze Plugs

RyanZJ · 03-08-2008, 04:37 PM

Looks like I finally found the source of my coolant leak. Anybody have any experience/tips for replacing freeze plugs?

RyanZJ · 03-08-2008, 06:57 PM

So I was unable to find much in my FSM regarding replacement, but I did find a section talking about oil plugs that look similar. It says to put a screwdriver on the bottom lip and hit it with a hammer until it twists in the hole, and then pull it out with pliers. Sounds simple enough?

Or, I've thought about just cleaning up the area where it's leaking, and putting some gasket maker or JB Weld on the area to see if I can stop the leak. It would be a pretty rigged fix, but I'm thinking it would work?

powerwagon67 · 03-09-2008, 06:10 AM

Yup! Use a screwdriver and a pliers or channel locks to get it out. Clean the surface well with some fine sandpaper as well as the outside of the new plug. Make sure there is no antifreeze seeping around the hole. Dry it out good. Put a fine skim amount of rtv silocone around the plug and smack it in. The best is to put a socket that fits nice in the plug and hit that when installing it. You may have to drop your exhaust to be able to work on that one easier.

RyanZJ · 03-09-2008, 08:47 AM

Thanks for the reply! Looks like I've got today's project figured out. It looked simple enough, just wanted to see if I was missing anything. I'm thinking the exhaust will have to be dropped for sure.

Naturalhoosier · 03-09-2008, 12:55 PM

Glad you found your source Ryan!!!!! Do you have the green covered FSM? I've looked in mine and it doesn't say much either.

What's the plug look like pre-install? Just looking at the pics, it looks likes a quarter-slug. I'm sure it's not...but that's just what it looks like.

RyanZJ · 03-10-2008, 07:46 AM

The FSM I have is in PDF format on my computer, so I even searched the glossary using CTRL+F and still didn't find anything. They look like little cups...basically what you see in those pictures is what you get.

Now the bad news. Of course the plug that's gone bad is right behind the exhaust y-pipe on the driver's side. I'd be able to remove it without taking out the exhuast, but there's no way I'd be able to put it back in. So, now I can either take a half day to remove the y-pipe at the headers and replace the plug, or I can try one of the expandable plugs that auto parts stores have. Anybody ever used one of these?

newracer · 03-10-2008, 09:01 AM

I have not used one in a freeze plug application but I have used those in a plumbing application and they work well.

RyanZJ · 03-10-2008, 09:04 AM

Sounds like it's worth a try at least.

millermp77 · 02-15-2009, 01:45 PM

I just purshased a 1998 Grand Cherokee with the I6 4.0L wich needs a rear freeze plug replaced, my question is did that expandable plug work for you??? and did you have to drop the exhaust or is there a way to do replace it without droping it?? I have been looking for manuals and they are very hard to find here in the UK.

RyanZJ · 02-16-2009, 10:24 AM

Its still leaking, but only because I haven't taken the time to pull the exhaust to replace it with anything yet. It's on my list of things to do this spring. I'm not even going to bother with an expandable one; I'm just going to replace it with brass when I do it.

KUK9 · 02-16-2009, 08:01 PM

Freeze plugs suck. It's always the ones that are the hardest to get to that leak. Best advice to give - get as much out of the way so that you can get a really straight shot on the plug when putting the new one back in. And make sure that you get the right size - CQ and NAPA have a ton to choose from, and they always seem to give you the one that is just a tiny bit off.

dickensheets · 02-20-2009, 06:55 PM

Get a mopar block heater for $30 and put in that hole.

They push in then tighten an expansion nut. Prob dont have to drop the pipe for this.

RyanZJ · 02-20-2009, 07:31 PM

It would probably not be worth it, but I'll look into it.

jeepmason86 · 06-11-2010, 11:21 AM

i have a 94 cherokee with leakingg freeze plugs and i am lookinf to put the rubber ones in myself.... is this a reasonable task for me to do myself??

**jeepster93** · 06-13-2010, 09:09 AM

I replaced a freeze plug in my van, a couple months ago.
Not a hard job at all. however sometimes they are in some very hard to reach places.
I tried to install a replacement plug and could not get to it well enough to press it in. The engine would have needed to be pulled to get to it well enough.
I got one of those expansion plugs shown above. It went right in zip, zip. That was 4,000 miles ago...no issues, no leaks.
An easy do-it-yourself project!