On Fri, 21 Aug 2015 09:03:21 -0500, "Terry Coombs"
wrote:

My little tractor has had a mishap , it put a con rod out the side of the
motor . Motor in question is a Kohler KT17 opposed twin . Since these are
rather hard - and expensive - to replace , I would like to repair the hole
by welding a patch over it . This unit is over 30 years old and oil soaked
,,, I've had reasonable success a couple of times , but nothing I'd write
home about , and I'm pretty sure the reason is I haven't been getting all
the oil out of the pores .
How long and at what temp do I need to bake this thing to be reasonably
sure I've got most of the oil out ? It will be degreased with solvent first
followed by a thorough scrubbing with detergent before baking . The part
looks to be die cast , which I believe means it has a fair percentage of
silicon in the alloy , which rod is recommended ? I have on hand 4043 and
5356 , but can get other if needed .
Or do I just need to bite the bullet and drop 130 bucks on a replacement ?
There is one on fleabay right now ... it's not that I don't have the money ,
I just hate to replace something that I can repair .

Many years ago I TIG welded a spot, that was missing a small chunk, on
an Aluminum side cover on a Harley for a biker friend. I used a std Al
rod, whatever that was. He had cleaned it up before he brought it
over. Apparently he did a good job as I never had any complaints. IIRC
he mentioned something about boiling it in acetone. How about maybe
finding someone who has a vapor de-greaser or maybe a steam cleaner?
If it's not in a critical place maybe you could make a cover plate and
just bolt it on using a gasket to prevent leaks.