924Board.org

[bureau13]

I am definitely in favor of it being that o-ring. To be honest, I'm not sure about the bracket. I've never actually had the lower charge tube off, I don't think. I will definitely take a look!
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1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)

[bureau13]

Minor update: I removed the upper and lower charge tubes. I do NOT have the bracket on the lower tube, for what it's worth. I'm betting that thing is NLA, but probably not a super popular item from wrecks. I'll keep my eye out.

The o-ring itself was not torn or anything, but it was a bit squished, and the lower tube came off the turbo a bit easier than I would have thought. I'm betting this is indeed the problem, and a new o-ring is on the way...
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1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)

[Fasteddie313]

Without that bracket, boost pressure in the pipe will keep lifting it off the turbo..
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80 Turbo - Slightly Modified

[bureau13]

[jacobroufa]

There's a guy in southern IL that is parting out a few 931s on Marketplace that might have what you need:
https://www.facebook.com/marketplace/item/245639353517281
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1980 Porsche 931
1981 Porsche 924 Weissach

[bureau13]

Ooh, thanks for the tip! I will contact him...

[Mike9311]

One my first 80, I also did not have the bracket. It was my only 931 at the time so I never realized I was supposed to have one. No issues either even at 15 PSI. That was only a few times. Mostly 10-12

I remember when I finally saw there was a bracket. I was almost bummed that there was something else to remove if I had to take things apart.
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1980 931 since 1989
1981 Ideola 931 Club Sport
1982 931 Entwicklungsfahrzeug
1979 924 NA ohne 650 mit 471
1982 931 Red Resurrection - 951 IC
1982 931 parts car / resurrection?
1980 924 NA (R&D lightweight)
1982 931 wana-be GTR race car

[bureau13]

The guy in Illinois had the bracket! So that's on the way, as is the o-ring. I hope that solves it....it seems likely that it will. Which is good, because with the Mittelmotor, Tial and boost controller, it's running great at 10psi, I replaced the leaky evaporator and I now have AC, and I swapped the shredded driver's seat back for a much better one from eBay, and I want to drive! Lol I hate finally having the car ready to go only to be grounded by a stupid o-ring...
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-----------------------------------------
1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)

[chuck21401]

[bureau13]

[Fasteddie313]

[bureau13]

Update: Crap! The o-ring did not fix the problem. Oddly enough, I did not have the rough running until it warms up problem...so maybe it did fix that. But light throttle I still get very lean readings and bucking. I need to put the smoke tester back on it and see if I can find a leak somewhere else.

This is the gods smacking me down for talking about adding more boost before I've fixed this basic problem.
_________________
-----------------------------------------
1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)

[bureau13]

Well, this is frustrating. Smoke seems to be coming out exactly the same as before. I don't get it. Maybe I can put an inspection mirror and try to catch it when it first appears. By the time I see it wafting up it's hard to pinpoint an origin.
_________________
-----------------------------------------
1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)

[bureau13]

It really does not appear to be coming from the o-ring I just replaced. It's possible that was contributing to the leak before, but the bulk of it seems to still be there. It also does not appear to be coming from the plate on the back side of the compressor. I cannot tell but the most likely candidate still seems that bypass valve cover. I'm far from 100% certain, but I certainly see some pretty dense smoke swirling in that area.

I put a wrench on those bolts and they were tight, but I could tighten the more. I don't want to overtorque them however. I can't think of anything to do at this point other than pop off that cover and replace the seals or whatever is in there.
_________________
-----------------------------------------
1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)

[Fasteddie313]

The only seals are under each cover with 4 bolts through them..
IIRC I made new ones out of oil soaked leather from an old welding apron or something..
I think the old gaskets were like red and crystallized when I did mine..

I'm not 100% sure it's possible, but I would definitely attempt to do it without pulling the turbo..

These kind of 4 angle open end wrenches are magic for tight places like that..


And maybe a ratcheting 10mm.. Possibly a stubby one..
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80 Turbo - Slightly Modified