Turbo internal wastegate q's

[thegreatestben]

Today I tracked down my mysterious noise which was a tick tick tick particularly noticable as I went down alleyways and past traffic barriers.
Spent ages looking for it, couldn't find it. Noise seemed to be getting worse/embarassing so I had another look today and found that the noise was caused by the wastegate flap.

At idle with the actuator on it makes the noise, a tick tick tick.
If I take the actuator off the noise gets quieter but somewhat still there.
If I open the flapper by hand the noise disappears.

Is the flapper suppose to close HARD against the turbine housing? Because the harder I apply pressure the more noticable my tick tick tick becomes.

I haven't played with a turbo like this before, so wasnt sure if the actuator is supposed to be holding the flapper hard up against the housing (this is how I've had it)

Or is it supposed to be sort of just in the right position for the flap to be just against?

What would you knowledgable bunch recommend I do to remedy this noise?

It's a TD05H twinscroll off've an Evo IV if that helps in any way

Video:

[feral4mr2]

with the wastegate closed feel around all the flanges/joins and see if you can feel any hot air being puffed out. you may be able to see some black soot around the flanges or even manifold runners from a crack where a leak will be present.
it does sound a little to me like a leak. when the wastegate is closed it may be allowing just that right amount of back pressure pre turbo to make the leak audible. when you rev the engine can you hear it more? specialy when it's cold.
small manifold leaks are sometimes a PIA to locate, they can radiate a ticking sound off curbs etc. and drive you mad!

[thegreatestben]

Thanks for the reply, the only leaks I can see are between the downpipe and the exhaust flange.
Would these be a problem, I didn't think so considering they are after the flap.
A turbo expert here in nz reckons my turbo is common for wearing out the sealing surface and there's not too much I can do. At least I know its not something harmful/serious

[mattysshop]

have the turbo faced, even if it's against the blade of a drop saw.. and the dump pipe flange also..

you don't have the gate to atmo do you? it's going into the dump pipe??

does he mean the little face of the flap? maybe it has a crack in it?

but you should have it faced anyway if the dump pipe gasket is blowing through.. if it keeps happening you might have to have it made with a thicker plate like a half inch plate..

[thegreatestben]

Its just the wastegate flap not sealing against the exhaust housing. It's not leaking from around the dump pipe, it's still using the evo factory item. It's not leaking anywhere else, which made it tricky trying to find the noise since it's occuring inside the dump pipe pretty much.
The turbo doesn't look like it's ever been split from the Dump pipe before, I'll just live with it until I have a decent reason to pull it apart. It's not causing any harm at the moment.

[mattysshop]

could be causing it to com on boost a bit slower?

my CT9 on the old starlet had a similar problem.. used an modified/old valve seat cutter in the head jig at a mate workshop worked a treat!!

[thegreatestben]

Yeah it won't be a problem to fix, have an engineering workshop for a garage.
Just don't want to pull it apart for such a minor problem.