So this is trivial by all accounts, but since the last time I did this was literally like 15 yrs ago, and it was the machine shop that provided me with the materials, I have no idea if the sealing "tech" has moved along since then?

I am looking for recommendations as to what should be used to seal up the regular block plugs. Small block here, so case in point: I have the lifter galley passege plugs at the back (by the distributor) and the matching plugs on the back wall, what do I seal them with?

My old 360 motor had the white paste (this is the stuff the machine shop provided me with). The current machine shop (where my 408 stroker block was done) just sealed the stuff up with what looks like silicon sealant, maybe "The Right Stuff" given the colour and texture? They used that on the water plugs as well, which I have not seen done before, but apparently that works for them today.

Is it OK to use that? Or should I be getting the "white paste", ha ha, whatever that paste may actually be (toss some product names at me please if that's the way to go).

Thanks!

https://www.permatex.com/products/g...form-a-gasket-no-1-sealant/?locale=en_us

Smear some in the openings and drive the plugs in.

agree have used #2 also.

I use Teflon pipe dope on pipe plugs but recently switched to using Indian Head sealer on soft plugs and really like it.

For soft plugs, #3 Permatex (aka the "brown death") The one, and only, thing it's good for.

Thanks for the responses you guys!

OK, so let me clarify, I am not looking to pop the water jacket plugs out. These are new, and unless someone tells me there is something inherenty wrong with the silicon based sealer the shop used, I'm not looking to remove and replace these. I'm assuming this stuff is just fine, and this shop has done thousands of motors (they are a well established shop), it's just that I've never seen that sealant material being used like that before.

I do have a follow-up question through regarding the suggested products. When you guys say "soft plug", what do you mean by that?

I'm literally talking about the threaded plugs that are normally between 0.5-0.75" in diameter, the plugs at the end of the lifter oil gallery.

EDIT
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I just went through my box of sealants and lubricants...I do have the ARP Thread Sealer. Reading the instructions it sounds like that would work for my intended use, makes sense?

I'm trying to avoid having to run out there looking for this...most places around here are either shut down for walk-in business (COVID) or let in one person at a time to pick up something specific that's been pre-ordered on-line or over the phone, i.e. no place for browsing around...LOL, which I get.

Heck, I drove 20 mins across town yesterday to pick up the 3 spray cans of PlastiCote DE1631 (Mopar Blue), having ordered them on-line back on Saturday.

soft plugs to me, are the cupped or flat core plugs found in the sides, or the front and back, of engine blocks and cylinder heads.
i usually use permatex #1 after a good cleaning of the block and plug. i think these are also called "welch" plugs by some ?
as to the threaded taper pipe plugs at the end of the lifter oil galley, loctite #567 white teflon paste works great ! that stuff is almost "anything" proof, and can be used with any material or combination of materials. stainless, brass, iron, you name it. i don't use anything but this on taper fittings. it's also good for high temperatures and pressures.

Permatex Aviation Form-a-Gasket #3. Pipe plugs, core plugs, valley pan end rails, intake manifold gaskets, water ports, and machined surfaces like VW air-cooled engine cases In 40 years it has never let me down. Brake cleaner for surface prep and clean-up.

the last ones i installed, i used 3M window urethane. It comes in a caulking tube.

I normally drive them in dry
I have seen some blocks with corrosion that made me use some thermostat gasket sealant on the edges, no leaks on them either

ok .....threaded plugs get teflon sealer here, except the ones "inside" they get nothing. Technically a tapered pipe thread relies on the threads to seal, I have used antiseize before also. The only thing I would worry about would be any rolled up rtv inside the galley coming loose. If it was applied to liberally.

This:

Plug Sealant

I've been bit by dry ones the first time it got really cold out a few started to weep. Had to pull them and apply the sealant. For a garaged car/hot rod that doesn't get exposed to freezing temps you'd likely be ok without it.

I've always used Permatex white teflon thread sealer.

Years ago I bought an ac delco freeze plug set and it came with red loctite, so I have always used that to set the plugs in and never had a problem.

Alright, so I picked up the Permatex High-Temp Thread Sealer #59214 in the US, #59206 in CA, product info here => Permatex Product Page

I cleaned the plugs and the engine block threads with brake cleaner...dried and applied the locker paste to all but the 1st thread on the plug, tightened tool tight...although the geek in me said: why isn't there a torque value anywhere???

For what it's worth, while researching this question I learned that the plugs or threaded connections in general apparently do not have torque readings and instead a Turn Past Hand/Finger Tight is the measure.

Thanks everone for the input and suggestions!

I have used Permatex #2 on every engine I have built. And have never had a leak.

I use ultra copper for all sealing needs. I use this stuff nearly every day a work also. Excellent product!

https://www.permatex.com/products/g...-rtv-silicone-gasket-maker/?locale=en_us

ultra copper IS good stuff, but if used in excess can create problems down the road.
ever see a radiator plugged with this stuff ? to say it ain't pretty is an understatement indeed ! this was used on the core plugs, water pump, water pump housing, thermostat housing, so they "wouldn't leak" [on a small block]. well, it didn't leak.
but the "excess" somehow found it's way into the radiator.........

I've used Indian Head on my old small block and my 2001 Dakota when a core plug rotted out and I replaced it.