Freeze Plug Repair

[helpme]

Have a friend with a leaking freeze plug on the back of the block. Has anybody tried patching one of these with JB Weld or UltraBlack?
Alternatively can you cut a hole in the firewall to facilitate changing it out?
Thanks.

 

[adsm08]

I have dealt first hand with the aftermath of trying JB Weld. I think it was actually a layer of JB Weld sealed in under Ultra Black. It actually held for a while, since I owned and drove that engine a little over a year before I found that particular piece of jackassery. However the plug continued rotting out behind it until there wasn't enough metal left to support it and the failure was catastrophic.

I generally don't recommend cutting holes in the firewall, but if that's what you gotta do to get in there that's what you gotta do.

 

[RonD]

The rubber expansion plugs are often easier to install in tight places.

And just for the record, they are not "freeze" plugs, they won't save the block if it should ever freeze that hard, popular name for them though.
The plugs fill the holes left when a block is cast with molten metal in a Sand Mold, you have to get the sand out after metal cools down so they have to leave these holes to do that, actual name is the Core hole and they are filled with Core Plugs.
Engine makers use the cheap metal plugs for cost reasons
Rubber plugs can last longer and are easier to install in some cases but cost alot more than the other kind, and no your block is NOT in danger of freezing and being damaged using rubber plugs,

 

[IIBRONCOS]

I second RonD on the rubber expansion plugs. I have an engine that has had a rubber expansion plug in the block for the past 17 years with absolutely no issues. My Bronco II has 6 rubber expansion plugs in the block and they are fairly easy to install and work great. Just clean the hole well with a metal bristle brush in a circular motion.
And don't forget the rubber plugs are designed to shrink when cold, ( which could push them out just like a metal one ) so check them when it gets cold. If you get a little drip from one you just need to tighten it a little.

 

[helpme]

Thanks.

Actually my friends truck is an an old F150 and he has all kinds of space behind the block.
The last freeze plug I changed was in a 76 Gremlin. But I suspect I'll be doing it in my ranger soon.