Burnt71

Is it necessary to use a sealer when replacing freeze plugs ? I have always put them in dry ?

PAmotorman

why take a chance of having a leaker.

stingr69

Always have used Indian Head for that. Why would you not?

Big2Bird

45 years, I have never used sealer, nor does the factory. I do use brass ones though.

As for sealer. I guess no harm no foul.

BlackC3vette

Yes, you can put it in dry. But, if it has a slight leak, then you have to go thru the trouble of removing and then re-installing. Of course the engine is back in the car at the time. What the factory did was based on time and cost factor spread out over the production run. So, I don't look at what the factory did or did not do as the holy grail. Freeze out plugs have long been an issue and I found a sealer made by Hercules (Blue Block) that does a great job. Just wear gloves putting it in, the stuff likes to get all over your hands and doesn't like to come off.

dmaxx3500

sealer is ok,just a little works wonders,,and use a large socket inside the cup and just knock it in

69Vett

in 50 years I have never heard of a freeze plug leaking, because it was installed dry.
But I do use the Brass version, they are softer and conform/seal better, and do not rust.

sunflower 1972

BlackC3vette

When you get somebody elses workmanship up on your lift, you get to see it all.

7T1vette

If you have all the original GM parts and the same tooling that was used to install them at the factory, you can install them dry and they will seal. Otherwise, wipe a bit of sealer on them...just for "funsies".

Why take any chance that they might leak.

Most lip seal casings and some cup plugs are treated with a sealing-paint type material on their mating surfaces. That is used as a sealant. If it's good enough for new parts, it should be appropriate for you.

PAmotorman

the holes machined surface could have been scratched when the original expansion plug was removed and the sealer will cover this problem

theandies

Can't hurt.

gungatim

I've always used a light coat of sealer on the plugs I install. helps lube a bit as it is pressed in and seals any irregularities in the block surface. I imagine brass seal better but I've always used steel. This is how I was taught in auto shop when I was a mechanic. never had a failure that way.

BlackC3vette

Brass plugs are really for marine engines or converting an engine over to marine use. Otherwise, steel is the normal, but brass is nice!

Big2Bird

15 responses on a freeze plug install.

It's like debating paper or plastic.

BlackC3vette

Freeze plugs do not come in either plastic or paper you silly rabbit.

fishslayer143

paper or plastic....

Burnt71

Now if I could only find American made freeze plugs

PAmotorman

it is no fun to find out you have a leaker after the engine is in the chassis.