Freeze plugs... and silicone.

DorianL

solid fixture here in the forum
Staff member
Reading around here I did not catch anything that specifically relates...

When reintalling freeze plug... sand bore, clean with acetone... dry.

Apply silicone sealer??? to the bore only and tap in freeze plug with a socket.

IIRC, I read generic "silicone sealer" somewhere. Is that right?

THANKS,

D.
 
NO! silicone is NOT the correct sealant

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BTW I have on several occasions seen guys who complain about various oil leaks on valve covers and rear seals ETC.
Used, engine parts will have oil embedded deeply into the micro surfaces.
almost all replacement parts will have a wax or grease preservative coating to prevent corrosion during shipping!
IF YOU simply wipe off oil soaked surfaces with a paper towel, who then smear on the sealant of there choice and proceed to install gaskets,
YOU WILL OCCASIONALLY HAVE LEAKS!

and then they wonder or maybe be in shock when you find the seeping oil leak has returned in a few weeks time!
metal surfaces may look smooth as glass but under a microscope they look like the surface of the moon , with lots of jagged surface cracks, so you really need to wash out the micro lubricants trapped in those cracks with a thin fast evaporating grease solvent and a lint free rag , followed by a second repeat of the process and in many cases a few minutes with a heat gun to dry and evaporate the solvent in the micro cracks ,
STOP AND READ THE SEALANT PACKAGE DIRECTIONS!
you'll generally find some rather amazing , bits of info such as temperature requirements, temperature limitations, what solvents work best to remove the cement or sealant, only after reading the directions, do you then smear the gasket sealant on both mating surfaces before bonding the two gasket & metal surfaces.(and in many cases you use a brush as dirt or oil on fingers prevents a good seal!)
pontiac
http://www.boxwrench.net/specs/pont_265-455.htm

chevy sb
http://www.boxwrench.net/specs/chevy_sb.htm

chevy BB
http://www.boxwrench.net/specs/chevy_bb.htm

426hemi
http://www.boxwrench.net/specs/hemi_426.htm

383-440 mopar
http://www.boxwrench.net/specs/bchrys_B.htm

318-340-360 mopar
http://www.boxwrench.net/specs/schrys_A.htm

ford 429-460
http://www.boxwrench.net/specs/ford_429-514.htm

302-351 windsor ford
http://www.boxwrench.net/specs/ford_302_351W.htm

351 cleveland ford
http://www.boxwrench.net/specs/ford_351C.htm

352-428 ford
http://www.boxwrench.net/specs/ford_352-428.htm
read thru these threads for more info

viewtopic.php?f=44&t=846&p=1284&hilit=sealant#p1284

viewtopic.php?f=50&t=50&p=1253&hilit=sealant#p1253

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first step is to remove the old freeze plug and accurately measure it, FREEZE plugs generally come in either zinc plated steel or BRASS, both work, but the steel deteriorates rapidly if you don,t use a 50% mix of anti-freeze in the coolant.
Once you know the correct size you then visit the local auto parts store and buy both a BRASS freeze plug of the proper size and the correct sealant.
Personally Id buy a complete set of brass freeze plugs and replace as many as you can easily access if they are STEEL, with the far more durable BRASS VERSIONS and next time the engines out of the car Id damn sure replace the rest.


having a seal or bearing driver tool to seat the freeze plugs correctly after brushing sealant on the block and edge of the BRASS freeze plug is helpful
http://www.harborfreight.com/18-piece-seal-driver-kit-35555.html
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that .032--.039 hole in the pass side oil passage plug will be Just fine !
the object off drilling the tiny hole for those that don,t know is two fold, first it prevent trapped air in the oil passage from slowing oil reaching the lifters as trapped air is bled off rapidly, secondly it provides a constant flow of extra lube flowing to the chain cam drive even at low rpms

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Thanks! Thought so. I found the source back; that is what was printed in my SA Book on How To Rebuild the Chevy Small Block.

Didn't seem right..

Thanks
 
question , on the front of the engine. the 3 main oil gallery plugs, when installing them. do they need to bottom out on the inside ridge, and also does any sealer need to be applied to them . i know they stake them in place so they wont move . thanks
 
Does anyone have a fix for an over sized hole for a freeze plug?


what size is the hole and what size freeze plug are you trying to use that won,t seal correctly?
is the block walls in the freeze plug hole in the block distorted, damaged or rusted badly?

yes rubber expansion freeze plugs can be an option

both brass , swage to fit and rubber expansion freeze plugs come in a wide selection of various diameters


https://www.amazon.com/s?k=rubber+expansion+freeze+plugs&i=automotive&ref=nb_sb_noss

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advance auto and other vendors sell them locally

measure the hole your trying to plug accurately
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clean the block carefully before you install the plug
coat the block and freeze plug contact surfaces with sealant just prior to install
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