911 2

Removed the exhaust and i have 4 broken turbo studs, exhaust side.
I drilled out one stud and will now tap a new thread.
I removed most of the swarf but some will have gone into the exhaust housing , on drilling and removal of the stud you can see, what i assume is the internal side of the exhaust housing, will this cause any problems on start up.
I can vacum into the exhaust housing but not sure what the internal structure is internally on the exhaust side and if the stud area is separate or forms part of the overall internal housing.
Does anyone please have a pic of the exhaust housing side from the inside
if there is any swarf, on start up would this be blown out the exhaust side or is there is a risk of swarf entering the engine

urquattro20Vt

Disclaimer - I've never had to drill out exhaust studs. But I would do whatever possible to remove all debris. I'd hate to see the any of the turbine blades get damaged.

Pretty sure the stud holes do not breach the housing - could see that messing up airflow.

Brandon
'91 Turbo

911 2

i could not have drilled through as i measured the stud length that protrudes into the housing,
I also put a light through the exhaust turbine end and could not see any light at the stud hole so i assume its closed
Im more worried the debris going into the engine than the turbo blades
Maybe if I held the turbine blade and started the car for a few secs that would clear any debris without damaging the blade
If anyone has a pic of the exh housing from the inside that would be very helpful

urquattro20Vt

debris cannot get into engine from the hot side (exhaust) of the turbo.

Brandon
'91 Turbo

911 2

what method do you use if they are rusted in

cobalt

I read your other post and see I misunderstood what you were asking. I have a spare K27 but I am not sure I can access it right now.

911 2

that would be great if you get a chance to take a look at it

urquattro20Vt

I have a spare K27 - please remind me what you need to see? If the exhaust stud holes enter the compressor housing?

Brandon
'91 Turbo

911 2

yes, if you could please check, do the exhaust studs enter the exhaust housing.
It is possible they may enter but the exhaust side turbine may have a separate area to the area where the studs sit, trying to confirm if drilling the stud may have sent swarf close to the exh turbine

urquattro20Vt

I pulled out my spare 7200 - and I cannot verify with 100% certainty as you just can't see into the scroll with the turbine in place. And cannot get a finger in there to feel.
But I cannot imagine those holes go through - as they would disturb airflow in there.
So I'd just carefully and slowly drill out.

If somebody has one disassembled that would tell you for sure.
Sorry I can't be better help.

Brandon
'91 Turbo

911 2

Thanks for checking
Any chance you could put up a pic of wherre the studs screw into, if there are no studs currently in the exhaust side, can you see if the hole goes through or is it closed on he end, or if you could possibly measure the depth of the hole from the surface

urquattro20Vt

my exhaust studs are in place on that turbo....

Brandon
'91 Turbo