924Board.org

Andrew NZ · Joined: 22 Jun 2004 Posts: 744 Location: New Zealand

Hi, my external wastegate has stopped working on my BAE turbo. It's not a 931 one, but it's very similar, so hopefully you can all help.

Basically I want to pull it apart to find out what's broken, but don't want to kill myself in the process. I assume I need to remove the six machine screws holding the cover on, but there's a warning label about the spring pressure etc.

If I use a G clamp and gradually release the cap off will it be safe? How much tension is it likely to be under?

9.3:1CR, 10+psi, an intercooler and extra injector are a lot of fun, but I'd like to play it safe and get it back to 6psi.

Out of interest there was no detonation at that pressure, so maybe one day in the future......
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Andrew
1977 RX924 race car
12a bridgeport supercharged
www.race4-dcup.co.nz

Tigger937 · Posted: Tue Mar 07, 2006 12:31 pm Post subject:

There's a fair amount of force there depending on the spring installed. I have the stock spring rated at 0.43-0.47 bar and could barely push it back together with one hand and use the other hand to thread the screws. I've heard of others with stiffer springs sitting on them to push back together and then threading the screws. To get an idea of the force, just loosen the screws a few turns without disengaging them and push the cover back into place by hand. But yeah, EXERCISE CAUTION!
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1981 931 (Concours)
1982 931 (Daily Driver)

"Think outside the box"

Smoothie · Posted: Tue Mar 07, 2006 12:41 pm Post subject:

When I took mine apart (the OE style 930/931 WG), I knelt down in front of it and said a brief prayer to the guardian saint of small disasters, then with the WG on the floor in front of me, loosened all the screws, then removed all except 2 opposite each other, then held the top down with one hand and removed the last 2 bolts - then with both hands on the top, let it up slowly.
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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

Andrew NZ · Joined: 22 Jun 2004 Posts: 744 Location: New Zealand

Lizard · Posted: Tue Mar 07, 2006 1:58 pm Post subject:

it isnt that strong, set it on the floor put one knee on top and then remove all the screws then slowely lift up
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3 928s,

Andrew NZ · Joined: 22 Jun 2004 Posts: 744 Location: New Zealand

Just got it apart, and the diaphram is leaking, so I guess it's a quick trip to the turbo specialists in the morning to see if they've got anything the right size. Fingers crossed!

On the plus side this is probably my mystery vacuum leak too, so hopefully some good will come of it after all.
_________________
Andrew
1977 RX924 race car
12a bridgeport supercharged
www.race4-dcup.co.nz

Andrew NZ · Joined: 22 Jun 2004 Posts: 744 Location: New Zealand

No parts available, so I bought a new one today instead. It bolted straight on and I now have a consistent 7.5 pounds boost. It goes quicker than ever now, and has a lot less lag, so I guess the old one must have been lifting the valve slightly well before it hit 6psi, before the diaphragm packed up.

Thanks for the help.
_________________
Andrew
1977 RX924 race car
12a bridgeport supercharged
www.race4-dcup.co.nz