I need to repair a damaged exaust port ( the area which fit in the muffler ) in a old engine. I can do it soldering a piece of aluminum using a product I can find here. It is called Technoweld and I think it is similar to any other aluminum solder welding ( low temp ) products you use in USA.
Question is .... Can I distort or damage the engine with temperature required for this kind of welding?

WhAt do you think?

Thanks

maybe TIG or WIG welding is the way to go.

there is always the possibility of doing harm to the engine with that amount of heat required by soldering or welding

mec

JB Weld could work. You might use some fiberglass with it to give it even more stregnth. I have used Bernzomatic Alluminum brazing rod on mufflers and tunned pipes, that could work too.

Yes, you're always risking heat distortion, and depending on what types of welding or brazing your use, heat treatment and/or remachining might be needed.

I've TIG welded broken aluminum fins back onto aluminum blocked motorcycle engines, but those are not load bearing and even a small motorcycle engine has way more metal to absorb the welding heat than the biggest model engine.

I'ver read about the low-temp Al brazing and have been curious to try it. Once thing that was correctly pointed out is that Al oxidizes easily and the oxides act as a barrier to puddle flowout. It'll probably take some practice to get it right.

Good luck.

The "Low Temp" aluminum brazing alloy is mostly zinc and not very strong. It is also very difficult to get the parent material sufficiently clean enough to tin readily. If TIG welding is properly done you hav a good chance. IT HAS TO BE CLEAN. No traces of oil Use a STAINLESS steel brush to clean the affected area and Solvent scrub Followed by a strong phosphate based cleaner like 409 or Eagle One cast aluminum wheel cleaner. A GOOD welder can work miracles a poor one and you'll need a miracle!

Good Luck

Are you a welder? I ask only because I am not and most welders around here, (Mtgy Al) have a $35.00 min for any job. Much less one like this. I would check the price of a new crankcase before I spent the money on welding cast. Would it also need some machine work to square off the edges etc?
Just something to consider.

Jimmy