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Giving head.

Ghostrider 67

Jack Stand Racer #6..and proud of it!
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LOL. Giving a head a chance to continue it's life on your engine. What would be a good permanent fix for a rear freeze plug on a head that is damaged? The PO put a expanding rubber plug in it and called it good. Not my style.
I want a permanent solution that looks good. It appears that someone ground down the plug boss but ran out of real estate before arriving at a sealable plug shape. How to build this back up? Discuss please.
First pic is the drivers side undamaged head.

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i think a good welder would be able to fix that.or maybe weld it closed as long as you dont let it freeze you should be good
 
i think a good welder would be able to fix that.or maybe weld it closed as long as you dont let it freeze you should be good
Are you referring to having metal added to the damaged area? Of so, how would you retain the perfect circle for the plug?
I wondered about welding in new metal 100% and re drilling the plug hole?
 
i have watched Dart Automotive weld up a cylinder head then use a c n c machine drill out the hole for the plug.
 
as 5.7 said weld it closed use a stainless steel washer as a plug then weld it closed. that is the cheap way.
 
Okay. thanks. I think I will do exactly that. Find a SS washer that's thicker than normal and weld it in there. Being on the backside is also good.
 
Since i am not much of a welder, and never on cast iron, i would die grind it as round as i could get it, then drill it the proper size for a pipe tap, tap and plug it . Maybe you could find a decorative plug, allen plug, or maybe chrome..
I think the BEST solution, would be to have someone who really knows what they are doing, weld it up.
 
Since i am not much of a welder, and never on cast iron, i would die grind it as round as i could get it, then drill it the proper size for a pipe tap, tap and plug it . Maybe you could find a decorative plug, allen plug, or maybe chrome..
I think the BEST solution, would be to have someone who really knows what they are doing, weld it up.
I agree...I would see if it is possible to tap it....

If not weld it shut as mentioned above...
 
I think I will contact PRH heads up in Burlington VT. They MUST have somebody who can do this.
 
Ooooffff!!!! Drill and tap is probably the best way to go as welding cast iron is not for an amateur.
 
You're not going to weld stainless to cast - PERIOD.

You don't need to "weld" that and you'd do more damage anyway.

Fix the damaged area with brazing rod - forget welding for that. Hit it with a die grinder afterwards and get the hole as round as you can then install your plug. And the hole doesn't need to be perfectly round when finished, those plugs are a tight fit and will conform to a bit of distortion.
 
Cast iron isn't as hard to weld as many are lead to believe. The area has to be pre heated to about 500 deg. F. but not too much more otherwise the cast iron becomes unstable. Clean the area of previous contaminants, I like to put my cast iron rod in the oven at about 100 deg. F. for a bit before I strike an arc. Weld short beads around the hole until you've added enough material to re-machine the hole diameter for the freeze plug. Don't let the welded area cool too fast, let it cool slowly. Take it to a machine shop if you don't have access to a mill.

You can tap it to accept a NPT plug if this is the route you decide to take (Boss 429 stuff) but be careful when you tighten the plug, you can crack the casting. If you don't know how to weld the best bet is to take it to a welding shop for this repair.....IMO
 
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Agree with Stanton braze it. Never worked with silver solder, would it work?
 
Cast iron isn't as hard to weld as many are lead to believe.

Whether its hard or not isn't the point. A weld in this are just isn't worth the effort unless you're a sucker for punishment !! Its not structural so why go to all the effort of preheating, purchasing special ni-rod, etc. when a simple braze will work. Hell, JB Weld would probably be good enough !!
 
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