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Short story. I pulled a perfectly good core plug out to see what condition it was in. It was good so I put it back. Now it's weeping and I can't get to it to remove and reseal.

What's the best method to seal it up? Straight water in the coolant so it creates some rust or something else?
 

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Alumaseal would be my first choice.
 

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The only one I have seen personally is that it will accumulate around the vent in the radiator cap abnd while i have not had any issues from it doing so I will rinse it off when ever i remove the cap until it stops doing so.
Its basically finely powdered aluminum with some sort of additives it does not ever set up just migrates to the leak lodges in it and sets up from cooling system pressure alone.
 

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Not surprised the core plug is leaking. They are a one time use item. When they are installed the first time they deform to match the contour of the hole. These holes are not machined perfectly round so if you are off even a little they have no chance of resealing. Even if you do get them exactly back in the same spot they may not seal due to the slight amount of taper they are produced with is no longer there. Never been a fan of any of those stop leak products, only time I'd use them is if I was planning on getting rid of the vehicle soon. Myself I'd pull the motor and replace the core plug with a new one.
 

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Try a couple of teaspoons of fine ground black pepper, will only solidify where the weep is the rest will just circulate, has saved me a few times, if the weep is too great and it doesn't stop you can safely flush it out and try something else. Alumaseal does work but will gradually gum up your coolant system.
 

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Try a couple of teaspoons of fine ground black pepper, will only solidify where the weep is the rest will just circulate, has saved me a few times, if the weep is too great and it doesn't stop you can safely flush it out and try something else. Alumaseal does work but will gradually gum up your coolant system.
Thanks for chiming in. I have heard that pepper trick before but never tried it myself. It'll be the easiest and quickest to try.
 

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Not surprised the core plug is leaking. They are a one time use item. When they are installed the first time they deform to match the contour of the hole. These holes are not machined perfectly round so if you are off even a little they have no chance of resealing. Even if you do get them exactly back in the same spot they may not seal due to the slight amount of taper they are produced with is no longer there. Never been a fan of any of those stop leak products, only time I'd use them is if I was planning on getting rid of the vehicle soon. Myself I'd pull the motor and replace the core plug with a new one.
Yeah I know. I was expecting this one to be rusted thin on the back. But it was perfect. I was going to buy another but forgot until it was too late (tight window of time to get the engine together and in).

Long term the engine is coming out again to replace it. But it won't be this year so I want to reduce the leaking until then.
 

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Yeah I know. I was expecting this one to be rusted thin on the back. But it was perfect. I was going to buy another but forgot until it was too late (tight window of time to get the engine together and in).

Long term the engine is coming out again to replace it. But it won't be this year so I want to reduce the leaking until then.
I also have used black pepper and it will seal leaks. just throw in 2 or 3 teaspoons of black pepper and drive it. it`ll take a while but it WILL seal your leak.
 

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You will notice that freeze plugs are not exactly flat on the back side, if you must re-use one, look at the radias flatten it slightly by holding a flat strap of steel on top, hit with hammer, not to much, this will cause it to spread wider. Or use a large socket on the inside, with the radias on a firm steel surface Wipe Lock-tight generously in the hole & pound in plug useing a socket that is as large as possible. Worked for me!
 

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Last night I finally got around to siphoning out the radiator and filling with water and half a 50g bag of ground black pepper. It's really interesting how finely the pepper disperses in the water, which is obviously how it gets around.

Too early yet to see if it helps. But fingers crossed. It should be back road legal next week. I had a hazard switch break internally and take out the indicators. Quick final fix after hours of tracing wires over 2 months.
 

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...
I KNOW YOU GUYS have got to be a lot younger than I am..But since you went to the Black Pepper .. I'll add a few more of the old school repairs..
SO GET YOURSELF A HORSE APPLE.. A GOOD DRY ONE . What's a horse apple ..Well it's just horse chit.. Yes take a DRY horse apple & roll IT INTO the water in the radiator... It swells just like the pepper.
.... SO What else .. THERES another old product called ... STOP-IT... It's ground up.. Very DRY cedar post ... & brake fluid.. The brake fluid works as a water pump lubricant. & It will also swell the W/P SEALS ..
... & SEEMS LIKE THERE WAS ANOTHER ONE .. Tonight I'm thinking a raw egg into a hot radiator .. But I can't remember.
& That ALUNINUM SEAL. I believe it's just more saw dust aka ground up cedar post & aluminum paint with out much dryer in the paint. Back in the day techs used to spray theur metal head gaskets with silver paint .. Old time silver paint didn't dry very fast so it made a good sealer.
 
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