Soft Plug Replacement

[pnw_oldmags]

Been working on a 53 Kaiser Manhattan ... trying to bring it back to the road.  It was neglected for 10 or 15 years.  One of the Soft plugs was leaking.  Scrapping on it I poked the screw driver right through it.  When I pulled it out you could see the electrolicis working on it.  Anti-freeze went bad??  I have pulled all five of the the plugs. 

Any hints on what size to put back in??  And how??  Use a hammer??

I wonder if this aluminum reaction is what took out the heater control valve also??

Any thoughts will be appreciated.  THANKS

[pnw_oldmags]

Looking through the KF Parts Interchange it shows 226 Engine - Freeze Plugs - Brass 1 5/8 - Napa 219-7126.  If they would have been brass ones they probably would not have failed.

[Fid]

I've installed plenty of aluminum ones in the Henry Js and they always worked fine. I clean the surface very well with a banana knife or something that will get into the groove and remove any debris. I use two ball-peen hammers. I set the new plug in (I've heard people say run a ring of Permatex gasket sealer around it) and take the ball end of a one hammer and hold it against the plug. Then take the other hammer and hit the peen end of the one I'm holding the plug with. That spreads it out evenly and it will seal well. Also, you don't have worry about hitting the center of the plug since you're hitting the end of the hammer instead of the directly contacting the plug.

[grcdirtmod]

aluminum plugs will always beakdown when next to iron their chemistry is not compatible. if you can the rtv method works the best to stop any small leaks also always use distilled or ro water to assure pH is right that will extend life of all the cooling system even copper will erode if off by much on pH 50/50 mix is best along with water pump lube and sealer to stop those pesty little drips Gary The Dirtmod

[pnw_oldmags]

Well this has been fun so far... There was 3 of the plugs leaking ... punched a screwdriver through one scrapping on it.

When I got the plugs out you could see electrolysis etching on the back of them.

Only a bit depressed when I read in the manual there is a 6th plug on the back of the block ... against the firewall.
Manual says drill a 2 1/2 inch hole in the firewall to replace the plug.  Gulp.
Hate to do that but really don't want to pull the engine.

[kenneth]

 Hi it is possible to replace the last plug without pulling the engine or drilling a hole in the firewall Ive done it on my -53.
Take down the trans,easy task if its not an automatic,then drill a hole in the old plug put a slidepuller in the hole and bang it out,put some sealer on the new plug and a socket that fits in the plug and tap in to place,worked for me!

[boatingbill]

I would recommend not using a socket or hammer to install frost plugs. You can overdrive the plug too far into the engine and restrict water flow or worse-drive it into the water jacket.  I recommend a oak block placed against the frost plug at the 3 and 9 o'clock position and drive it in a little and then put the oak block at the 6 and 12 o'clock position and drive it in some more. Alternate back and forth until the oak block hits the engine block and the frost plug will be fully seated. This way it is impossible to over drive the frost plug into the block. I learned this the way we learn most things, the hard way!