18bora, curious as to what rod you are looking at in the link you provided? I would have looked for a piece of stainless--( and likely been way off). Recommendation?

Is your turbo the kai version, which according to HKS is the upgraded version. Just curious.

he linked invar which doesnt expand much with heat. I think a poor choice. the housing and bearing will expand and if shaft does not, it will leak. its pretty important to get the metal composition right.

Isn't the HKS 7640 notorious for warping issues? Never really been a fan of HKS products...

Yeah, some homework is in order:
https://en.wikipedia.org/wiki/Superalloy

At Garrett they use Inconel for the CHRA shaft and Mar-M 247 for the turbine wheel on TR-30R's. The turbine housing is often a very thin Inconel as well (non-containment).

Not knowing what materials are used for the rest of the flapper assembly it'll be a bit of a trick to figure out the correct filler rod material.

It's the fist version, non kia
Inconel has a high nickel content, the Invar is very close. Strong, high heat tolerance and low expansion, which makes the shaft less likely to bind. As for leaking, the shaft/bearing assembly is never 100% sealed.

Invar (Alloy 36)
http://www.mcmaster.com/#9051kac/=r1tk8n
Chemical Composition (%) of Invar—Nickel makes up the remaining percentage.
Iron Chromium Molybdenum Cobalt Titanium Carbon Manganese Silicon Aluminum Other
63% 0.50% max. 0.50% max. 0.050% max. 0.10% max. 0.050% max. 0.60% max. 0.40% max. 0.01% max. 0.250% m

I had Invar (left) and Titanium (right) in my hand today.

Buy a cracked housing and steal the flapper assem

that was my thought to fix mine. i wanted to use mitsu shaft and bearing that i knew would work well. problem is the dang hks shaft and bearing size doesnt match anything mistu used. the hks setup is longer. and the bearing is bigger diameter on the hks as well.

Can you turn a bushing to adapt it?( saving metallurgy r&d) which seems to yield the same down time diagnosing as it does to fix. I had an old kinugawa housing around that shat the bucket I can see if it's still here incase the dimensions varied to your favor.

Ps shat is the past tense of **** and not filtered ? Lol

I hate experiments like this. done too many in the past that just didnt work. I think bora is on the right track. thinking more about the leak issue. even when shaft is pretty loose they dont really leak much if at all. the wastegate spring pulling on arm causes arm to try to pull out of housing. so inner arm seals against the bearing face.

I would call garrett and see if you can get some material tech. they are warrantying evo x bolt on turbos for failed wastegate flappers. seems they will be up on proper fix..

You're saying the EvoX Garrett turbo had/has the same failure?

Info on the Garrett update:
http://www.turbobygarrett.com/turbob...t#.UyCVp2TCOKQ

So what did you do and how did it work?
Mines leaking pretty bad so I'm on the same road...

I almost forgot about this. The turbo and the parts are is still sitting in the garage somewhere, haven't had a chance to finish it, just too busy with other stuff.