Absolutely not sure about this.

Sharp material, silica carbide he said, would want to be damn sure there was absolutely no residue before assembling. This is the mob that did a story on a 750SFC on fb, they knew almost nothing about the bike and got their back up when I pointed this out.
 
Residue is one part, that's relatively easy.  A lot of work, but easy.  My worry would be what ends up embedded in the alloy surface, only waiting for oil and heat to release it into the circulating lube.  :(  Silica carbide... doesn't get much harder than that, bearings won't last more than a couple of minutes seconds!

Supposedly/theoretically, the liquid should prevent the media from embedding itself, but who's going to guarantee that?

piet
 
I do have first hand experience with this, albeit with a large boiler feed pump oil reservoir.
After blasting and a most thorough clean up,  it took around 5 seconds to completely block the oil filter with blast media when the oil pump started.
It took around 100 filter cleans to clear the almost invisible carbides from the system. Lord knows how much damage was avoided with effective filtration!
 
I have been having engine parts vapour blast cleaned for a good few years now, I think they use glass, but not sure, all seems well, if once back home more cleaning is done, after natural drying a good blowing off with compressed air at 150PSI is a good start, running a tap in every single female thread (which had bolts screwed into them before cleaning (check the video again!) and blasting the hole with air with the tap rising and falling in the thread and again when clear of it, then soap and water, (car wash soap has no salt) and finally ....I did at one time have a dishwasher, in my cellar, and with no salt or detergent, put the parts through a couple of wash cycles, that did seem to really get them clean and free of any media, Never quite sure of anything has embedded into the pores, but at least the dishwasher heats them and cleans with steam, must get another, I cannot quite bear to use the one in the kitchen.,
CLEM
 
I would have thought making some alloy plates and using the existing bolt holes to seal the cases would be easier and safer or even using soda or aqua blasting using water-soluble media again would have way less purtensal long term risk. The stuff there using is what oil stones are made out off, makes me cringe just thinking about it.
 
No problem at all to do the outsides of engines, insides are another matter.

I bead blast loads of engine components, but always try not to get to the inside surfaces with pressurised media.  Lots of effort to get it all out, blanking and masking is often quite ineffective.  No great difference removing a shovel- or teaspoonfull of glass beads.  Probably takes longer to blank/mask effectively than cleaning out an unmasked crankcase.  As Clem describes, every single thread needs to be chased, lots of liquid and compressed air is needed to ensure peace of mind.  3-4 hours to clean out a set of crankcases is quite normal.

piet
 
Dodge City. Pity the poor sod who ever ends with them as the DPO! I made a rough cover out of 5-ply to seal the gearbox selector cover when I did some chemical cleaning on a friend's SF motor. I'm sure it wouldn't be too hard to make one for the primary cover and barrel surface and blast to your heart's content. I reckon you could have the tope end fitted and blast without any baddies getting in too.

Mine were walnut shell particle blasted - came up beautifully. Didn't seal the innards, but you can be sure I'll be thoroughly cleaning and recleaning the guts before it ever gets used. Ditto cylinder liners after a rebore/hone, clean, clean and clean again until a snow-white cloth comes away with zero trace of grey matter.
 
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