How to deflect aluminum flakes when using a circular saw ?

Did the damage cause a loss of transaxle fluid? or did it cause loss of inverter coolant? or both? Before you go damaging this further with a saw, you need to know if that "tubular" passage was used for oil or coolant to flow through and what the consequences may be if you block it. A circular saw is a rather brutal machine for trying to do precision work. If I had no choice and had to, I would use one of the vibrating saws with a metal cutting blade. If that passage is not critical, I would probably just take a soft metal or wood dowel rod of the right diameter, coat it with JB Weld and push it up into the tube-like passage, where it could seal everything. Once it's in there acting as a backer rod, you could slather more JB weld onto the exterior like a super thick layer of paint.
If that 'tubular" passage is actually a coolant or oil flow path, I might try to use a correctly sized copper tube a couple inches longer than needed. Drill a hole in the side to align with the other hole/passage. then do the same thing. Cover it with JB weld and push it up into the tubular passage and position it so the hole I drilled lines up properly to complete the flow path. There should be a couple inches of tube sticking out that you can crush and solder to seal it, or trim it and solder/JBweld on a cap. Then slap some JB weld all around the tube area to completely seal it.

The general idea is to install a plugging device if it's not a critical flow path, or install a repair sleeve into the inner diameter if it is a flow path. That's just general ideas, hard to give precise info without actually seeing it in person. Not the most ideal method of repair, but it will do in a pinch. Do a little reading up on installing repair sleeves. The hole looks like it may have some 'crush' damage, which could require running a drill bit up into it to true it up, but that's no big deal, and if the wall thickness is decent, you can make it match the OD of the sleeve better.

 

Do you mean “oscillating tool”, one of these:


(Recently got one myself, finding it very handy, and relatively easy to control.)

 

OP's previous post : https://priuschat.com/index.php?posts/3478288

 

At least thread #3 lol:

2015 prius c hybrid inverter cracked casing | PriusChat

 

This is amazing, all the best!

 

Yeah, I had glanced back through those threads and thought I had seen that he mentioned "hybrid engine oil" and also that inverter coolant had drained. I'm just not clear on which or both. It looks likely to me that vertical "tubular" portion intersects the horizontal opening to create a flow path. Without being there or having a handy example to look at, idk. If there's no other damage, it's just a matter of repairing the flow path, and that can be done relatively easy using a 'custom sleeve'. A shop isn't going to do that, but a good DIYer sure can.

I'd also be a bit concerned about those cracks in the background. They look like cracks caused by the passage being slightly crushed to an oval shape. If those cracks are in part of the casting that physically separates two fluids, then the repair gets a lot more complicated.

 

Well, if it helps I read that the transaxle used in the Prius c doesn't have a water cooling loop. The WS ATF is the only fluid present in that version of the trans.

 

... and even in the gen 3 liftback, the coolant loop is just a superficial loop on the side of the case, and another loop inside next to MG1's stator.

This looks very much like the oil passage up to the oil pump in the end plate of the case.

 

Call (GM) gasketmaster and ask them how much ? If you need a circular saw to fix that I'm pretty sure you'll be sorry you didn't call.
If you're serious about a pipe and JB - damn - you can take a look at how shops put helicoils in head while the head is still on the block. Keep in mind the saw blade is gonna shoot flakes into the case if you cut all the way through the case, so worrying about flakes getting in through the hole is pointless. The flakes will be in there unless you know what you are cutting into where ever you are cutting.

 

That is the exact question I was hoping you could answer for us.
Why is that hole there?

 

Questions like that are the kind the New Car Features manual is for, which wouldn't be a bad place to look with a situation like this if you haven't already.

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