Anyone used rubber plugs in place of metal freeze plugs?

[Texas1971]

Just removed a bad metal one from '68 327 and wondered if I could use one of the rubber expansion plugs in its place. The kind that has the nut in the center that expands as you compress it. Anyone had good luck with this? Y'all have been great with the advice as I've been slowly moving along!

[airdale94]

I tried one once and blew it out. I might not have got it tight enough though.

[Texas1971]

Thanks. I know they are 1 5/8" so I got the plug that expands up to that. The next size starts at 1 5/8 and goes up to 1 3/4. I guess I can try them both. Any thoughts appreciated.

[sodak69c10]

i guess i have never used the rubber ones but i have put plenty of block heaters in before they work the same way and they stay in, (i wonder if a person can loctite the bolt to help keep them tight?)

[fine69]

They work well. Several of them in my 67 Cougar right now. Just make sure they are all the way in before you tighten them down.
Used them for years.

[Texas1971]

Hey Fine69! Did you put any silicone on 'em? I like the locktite idea.

[Tx Firefighter]

I had opposite results. Mine always popped out.

[Longhorn Man]

while the comparison to block heaters holds water(no pun intended) I have had to replace several of the rubber ones over the years turning wrenches... probably 3 or 4 a year.
Why don't you want to install a new steel one... or better yet, brass?
What ever you do, if it rusted out, there's probably gobs of rusty sludge in there, try to get as much of it out.

[truckdude239]

i agree i pulled one out of a 402 that we are rebuilding in class and it was rough why no take the time to flush the block and install a new steel plug i use red locktite on my plugs always worked well

[AuggieStyle]

bought an 87 ram charger in 93 that had a bad freeze plug. I replaced the freeze plug with an expanding rubber one, my dad laughed said it wouldnt work well it sorta didnt I had to replace the freeze plug 3 years ago so eleven years was the limit. for mine.

[grayw0lf]

Been there, done that. I made it super tight when I put it in. It held for 3 years.

They are good in pinch, but I'd definately recommend metal.

[rwgregory]

In my opinion, the rubber expansion plugs are fine to carry in your toolbox in case you blow a freeze plug on the road. They will definately get you home where you can replace it with a metal one. Let me share a trick I learned from a retired mechanic when installing metal freeze plugs. Coat the outside of the plug with aluminized spray paint. The wet paint will lubricate the plug to help drive it in easier and after the paint dries it will act as a sealer and rust inhibiter.

[GREASEMONKEY72]

Originally Posted by rwgregory

Coat the outside of the plug with aluminized spray paint. The wet paint will lubricate the plug to help drive it in easier and after the paint dries it will act as a sealer and rust inhibiter.

ill have to remember that