Freeze plugs

[Joe Z]

I have used this site for advice on my 1988 Cherokee and wanted to post something that may be useful to someone. I recently replaced my freeze plugs on the side of the block and back of the head. They were extremely difficult to get in (incredibly tight) but finally got them driven in. I certainly didn’t drive them in correctly, as in didn’t use the right tool, but regardless, got them in. They looked great. Got everything back together and it started right up. Had an unrelated fuel leak so turned it off immediately. Looked underneath and sure enough had a freeze plug or two seeping…..very frustrating. Once I got the fuel leak taken care of and after sitting for a few days, started it again and let it come up to temperature. So far no more leaks or seeping around the freeze plugs. Just wanted to post this in case anyone else runs into the same issue upon installing new ones. My experience was give it a little time, and there’s a good chance they will seal themselves. It may be the heat or enough surface corrosion had to develop, but they are now not leaking.

 

[PNWOLYXJ]

I would keep my eye on that. Generally there is no self healing feature and freeze plugs are pressure fit. I’d consider double checking that they are seated correctly. Worst mistake I’ve seen as a mechanic is someone telling me it stopped leaking and it turned out it was empty. Hopefully you are lucky and it was the temp that helped it pop into place, but antifreeze is not a place to accept risk… engine failure is not a cheap or quick fix. Best of luck.

 

[75SV1]

I like to use brass freeze plugs. Also, there are sealing compounds.

 

[Joe Z]

I would keep my eye on that. Generally there is no self healing feature and freeze plugs are pressure fit. I’d consider double checking that they are seated correctly. Worst mistake I’ve seen as a mechanic is someone telling me it stopped leaking and it turned out it was empty. Hopefully you are lucky and it was the temp that helped it pop into place, but antifreeze is not a place to accept risk… engine failure is not a cheap or quick fix. Best of luck.

Absolutely keeping an eye on them.

 

[Joe Z]

I like to use brass freeze plugs. Also, there are sealing compounds.

Used brass with Permatex Aviation sealant.