Exhaust Port Hole Patching

Over the holidays, we found a friend, Ken, who has the skill, equipment, and willing to help us.  Reviewing the trouble, Ken thinks it is possible to TIG weld the aluminium if it is cleaned really well.  So, after some scrubbing and washing the port, we got it cleaned and ready.  (This also make for a good picture to see the hole into the cylinder's water jacket.)

With everything set I load the motor into the back of Daws headed to Ken's.  After some test runs, Ken got going welding to close the hole.

It started well, as Ken laid down some welds in front of the hole.  As he moved back problems started.  The edges were thin and the heat needed to weld would vaporize the aluminum.  This made the hole bigger, and more material was needed to be laid down to fill the ever enlarging hole.  As he worked, I could do nothing.   At first I listened and could hear the weld arc ebb and flow.  This got me anxious, so I began to pace like an expectant parent.  After an interminable period of time (really about 20 minutes) Ken announced he had finished.

To test this patch we devised a pressure test.  The coolant return line was tapped off, a cap with a valve stem was placed on the coolant feed line.  I then used a bike pump and Ken would look and listen to see if the patch held.  After some amusing start that only jury rigging brings, we found the patch was leaking.  So, Ken went at it with the welder again to see if he could fix it.  This time the welding did not go well.  The pneumatic test had pushed enough containment into the patch that the second attempt to weld did not stick and mostly balled up.  After a lot of effort, little could be done.  So, with a brief Hail Mary test, it was determined that the patch will not work.

sigh...

Thank you Ken for your efforts, sorry I did not give you much to work with.

Alrighty then, on to plan B.