C2 freeze plugs....brass vs steel

[Jim V.]

I understand there are a few issues when replacing C2 freeze plugs. Todays plugs are imprinted with size and in some cases logos, while original were unmarked. Most use brass plugs today due to their longevity; while originals were steel and I am told todays steel replacements are cheesy and will prematurely leak. Lastly, originals are deeper, roughly 1/2 deep vs replacements that are 3/8? deep.

So...here goes...

1. Is there a functional dissimilar metals issue with using brass given the aluminum radiator and supply tanks?

2. If using brass and patching in the stampings, will std. filler putties hold up to rigors of high engine heat? Is there

3. Is there a source for deep brass plugs?

4. Who today supplies the best repro steel plugs?

5. Is this much ado about nothing....is there a deduct for replacement plugs?

Thanks guys..

[Mike M.]

Re: C2 freeze plugs....brass vs steel

there will be a deduction if the judge places a magnet on the brass plugs. mike

[Jim R.]

Re: C2 freeze plugs....brass vs steel

I used the brass and filled them in ,I would be suprised if a gudge would use a magnet on them ,at the 2003 Rochester MN. meet i did not see anyone checking freeze plugs !

[Mark #28455]

Just make your car into a BB...

Then the judge won't be able to get to the freeze plugs with a magnet!

You could probably use a low temp solder with flux to fill in the stampings. The last set of brass ones I got from GM did not have any markings, only a little paper label that says "Made in Canada".

Mark

[Jim V.]

filling them in....

Jim....what did you fill them with? Thought the heat might be an issue in keeping a metal glaze in place.

No issues with dissimilar metal corrosion? Assuming you have aluminum radiator and surge tank.

Thanks....

[Jim V.]

BB...hey yeah...

The think anybody has ever magically "restored" a SB to a pricey BB.... No...nobody would do that.

I will check with the GM counter boys... I recall reading in the archives from a year old post that GM was discontinuing them.

Thanks

[Jim R.]

Re: filling them in....

Jim ,what i used was bonding adhesive ,may not be the best to use but have not had any problems ,other than a gudge with a magnet ,also good point on the type of metals torwards corrosion ,is this a pboblem with brass and alluminum.

[don22567]

Re: C2 freeze plugs....brass vs steel

Jim, I recently replaced the freeze plugs in my big block engine. Corvette Central has the correct steel plugs and they are the correct depth. LI Corvette has the wrong ones. Don.

[don22567]

Re: BB...hey yeah...

Jim, I had my GM parts guy at my Chevrolet dealership do a lookup on the part number for the steel freeze plugs. Although they have been discontinued he found a couple of dealerships that had a bunch on them still in stock. I bought a bunch of them that way too. Don.

[Jim R.]

Re: C2 freeze plugs....brass vs steel

jim brass plugs will have no effect with your alluminum radiator i called dewitts radiator and asked this question .

[Jim V.]

Re: C2 freeze plugs....brass vs steel

Thanks all. For my SB it turns out GM still carries the expansion plugs. Suppose I will give them a try.

Dave Dewitt also responded to my email supporting brass plugs as being a non-issue. He brought up the fact that GM has been using brass heater coils forever with aluminum radiators. Good point. It still is somewhat odd that GM went to such lengths on C2 overflow tank caps to have brass rivets for brass radiators and steel rivets for aluminum radiators.

Thanks all for your help as always.

[Mark #28455]

the cap is in electrical contact

You get galvanic corrosion when two dissimilar metals are in contact and there is an electrolyte present. So, the block and radiator are not in contact, yet a block and the aluminum heads are! Also, the cap and the radiator or the expansion tank are in contact.

Mark