welding to a freeze plug

Will welding or brazing a fitting to a freeze plug soften it up too much to stay put? I'm interested in some cooling modifications to an engine and wanted to see how feasible this approach would be.

Reply to
carl mciver
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Carl I can't answer your question directly, but what would the consequences be if the modified freeze plug failed? Not good at best. The newer type block heaters that pull in with a positive bolt arangement look to be a better engineered approach, but would require some machined fabrication. Or try it and see what happens.

You don't specifiy what type engine your working on but most have a NPT drain plug(s) somewhere that might serve your purposes.


Reply to

Freeze plus (more properly core plugs) are by design very soft steel. I doubt you could get them any softer if you tried.

Reply to
Rex B

Carl, If space permits, use a bulkhead AN fitting. Drill straight through it. Grind down the back of the fitting if needed (Well just don't chop in too close) Most freeze plugs are brass or a soft alloy as you already knew- Of your going to try this, just use a new plug and hope for the best. It's worth a shot... Just find the hardest plug you can.

All the best,


Fraser Competition Engines Chicago, IL.

Reply to

If you modify a new one and press it in _after_ having modified it.

Pay attention not to put load/momentum onto the plug, or it will come loose.


Reply to
Nick Müller

But you _might_ make them shrink enough during the cooling-off from welding to lose their seal.

My experience has been, unless you have ALL the toys on a vehicle, most every cooling jacket has at least one pipe plug in an unused port. Look all-round -- you'll probably find one in a place where you can't get it out, anyway .


Reply to
Lloyd E. Sponenburgh

That's how I get a stubborn freezeplug out (with coolant drained). Heat center red, metal expands and is plastic but the surrounding hole prevents it from expanding radially so it deforms some other way. But it can and does contract radially when it cools, and out she comes.

Reply to
Don Foreman

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