Leaking frost plug
Senior User
Joined: Apr 2001
Posts: 321
Likes: 1
Leaking frost plug
Hi Guys,
Quick question, my 1979 351M has a leaking "frost plug" above the starter motor on the block that leaks a small amount of coolant, just enough to drive me crazy.
Can I replace this plug with a new one with the engine in the truck, or do I need to go to a motor re-build shop to have it pressed in?
This motor is original, and I suspect that is why it is leaking.
Thanks for your help,
-Brents
Quick question, my 1979 351M has a leaking "frost plug" above the starter motor on the block that leaks a small amount of coolant, just enough to drive me crazy.
Can I replace this plug with a new one with the engine in the truck, or do I need to go to a motor re-build shop to have it pressed in?
This motor is original, and I suspect that is why it is leaking.
Thanks for your help,
-Brents
Tuned
Joined: Oct 2001
Posts: 328
Likes: 4
Leaking frost plug
As far as I know, you should be able to put it back in without too much effort. I'd suggest using a socket that fits the inside diameter
of the plug to drive it home. They're a pain to get started, but once they grab it's no big deal. Buy 2 in case you booger one up.
Good luck!
of the plug to drive it home. They're a pain to get started, but once they grab it's no big deal. Buy 2 in case you booger one up.
Good luck!
Posting Guru
Joined: Feb 2002
Posts: 2,404
Likes: 3
From: Cleveland, WI USA
Leaking frost plug
I see no reason to pull the engine. I just replaced a plug on my 460 (The one behind the motor mount). I jacked up the engine, removed the entire motor mount, CAREFULLY pounded the plug into the block then pulled it out with a pliers.
To install a the new plug, I used a freeze plug installer. It's a long, bent rod with different sized discs (for different sized plugs) that go on the end. It just allows you to hammer at it from goofy angles.
BTW, the plugs come in different depths. From what I've been told, the deeper the better.
Good luck.
Kevin K.
To install a the new plug, I used a freeze plug installer. It's a long, bent rod with different sized discs (for different sized plugs) that go on the end. It just allows you to hammer at it from goofy angles.
BTW, the plugs come in different depths. From what I've been told, the deeper the better.
Good luck.
Kevin K.
Senior User
Joined: Apr 2002
Posts: 406
Likes: 1
From: cedar rapids usa
Leaking frost plug
Have you tried to use a poor in sealant? Something like sliver solder or barb’s stop leak should do the trick. Prestone and a few other antifreeze company’s make their own brand now. Incase your wondering if this stuff could hurt your cooling system, every US auto maker now uses one kind of stop leak or another in there cooling systems from the factory.
Posting Guru
Joined: Feb 2002
Posts: 2,404
Likes: 3
From: Cleveland, WI USA
Leaking frost plug
>Have you tried to use a poor in sealant?
Wayne,
I thought of that too, but I'm glad I didn't use it. When I pulled the bad plug out, it was rusted so bad that one tap with the hammer almost completely removed the center of it.
I couldn't get a good view of the plug because of where it was, so I opted to just change it.
Kevin K.
Wayne,
I thought of that too, but I'm glad I didn't use it. When I pulled the bad plug out, it was rusted so bad that one tap with the hammer almost completely removed the center of it.
I couldn't get a good view of the plug because of where it was, so I opted to just change it.
Kevin K.
Senior User
Joined: Apr 2002
Posts: 406
Likes: 1
From: cedar rapids usa
Leaking frost plug
[updated:LAST EDITED ON 17-May-02 AT 05:39 PM (EST)]Good thing you did. I should have mentioned for him to take a good look at it first.
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Postmaster
Joined: Aug 2000
Posts: 3,312
Likes: 1
From: Eldorado Ca. USA
Leaking frost plug
Also.... applying a thin bead of form a gasket #2 to the plug and the block will help the sealing process as well. Dont settle for the steel plugs, cough up the extra $$$ for brass. Wont rot through like steel.
Tony
'77 F250, 4X4 460 transplantee, "Flamer"
'74 F250. 460, "beater" now "1 dead ford"
'73 F250, "midnight auto" now a trailer for the flamer
Tony
'77 F250, 4X4 460 transplantee, "Flamer"
'74 F250. 460, "beater" now "1 dead ford"
'73 F250, "midnight auto" now a trailer for the flamer
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Posting Guru
Joined: Jul 2001
Posts: 1,613
Likes: 2
From: Gainesville, FL
Leaking frost plug
Brents,
If you find yourself in a position which makes the installation difficult/impossible, they make an " Acorn Freeze Plug". It has a mechanicla fastener that tighens the plug into the block. I use them when I can't get the old block surfave clean enough for a seal.
Consider it,
KingFisher
If you find yourself in a position which makes the installation difficult/impossible, they make an " Acorn Freeze Plug". It has a mechanicla fastener that tighens the plug into the block. I use them when I can't get the old block surfave clean enough for a seal.
Consider it,
KingFisher