Quick Aluminium Compressor Repair

[NickH]

A friend bought a cheap compressor, catalog return, decent brand - Wolf, but didn't fill it with oil & test it before the end of the return for replacement/refund/repair period expired.
He asked me what he could seal a crack in the casting with, I volunteered to fix it but he wanted to have a go, but after a degrease & sealant application it still leaked all it's oil over a week.
He brought it over at the weekend & this is what I found



It wasn't just a crack, one of the mounting feet was broken out of the bottom of the crankcase. Cleaning revealed a crack from gasket face right to the back of the crankcase



I set the piston to TDC & stuffed a load of clean rag up the bore, used a carbide burr to vee all crack edges including the detached foot, fitted it up to ensure the gasket face would align, clamped the foot in place and fired up the MIG with 0.6mm Al wire and Argon, result after a little filing



TIG would undoubtedly make a neater job but the professional ESAB bodyshop MIG I'm using cost me £50 second hand and produces good structural welds, I could tidy the outside up fairly quickly but this repair will be covered by the cooling shroud so it will get cleaned & painted only.
Inside painted with clear 2 part epoxy to stabilise the filed metal to paint edges, a little metal repair epoxy on the gasket face to fill some small defects.



If I were charging I'm not sure this would be an economical repair as I have about 1 1/2 hours total including strip & rebuild in the job.
Since it's a favour for a friend who's letting me practice on his compressor it's a win-win situation,
Nick