924Board.org

[Ants]

If i take it to work tommorow i may be able to take photo's.

However in the mean time i can't get the damn thing apart. The air finned bit (with plunger) attaches to the vent bit via 3 bolts (in a triangle shape) which in turn attaches to the cylinder bit via about 6 bolts in a circle.
But i can't undo the 3 bolts in a triangle as yet to get inside it. Without shearing the bolts. I may have to drop it off at my local garage tommorow and see if they can do it.

[Smoothie]

I think you need to remove the 6 bolts to get at the spring and diaphram. Can you do that without removing the other 3 bolts?

I'm guessing you might need a gasket to reassemble once you separate the sections that are held together with the 3 bolts. Does that look right? I'd either leave them, or if you really need to remove them - put some penetrating oil on them, maybe tap them occasionally with a small hammer or something and let them sit a while. -Then try removing them again later.

[Smoothie]

If it's internally designed the way I think it is, you should be able to push the valve in from the opening in the bottom where the pipe from the exhaust manifold attaches. It should go up under pressure and close by spring pressure when you release it.

[Smoothie]

Well, the absent minded professor just put down a pretty good drawing of the wastegate internals... Then I went upstairs to scan it in and remembered the desktop computer is f'd. Is there someone I can fax it to in the US that's wiiling to take it and scan it in? -Then either post it or e-mail the scanned image back to me so I can post it? Contact me by e-mail if yer willin'.

[Smoothie]

Ah screw all of that. I made another diagram in Photoshop. Go to my website and click on "Wastegate Diagram" or http://knarfartanis.tripod.com/quotsmoothieswheelsquot/id9.html . Anyone that knows for sure how they work and can see anything wrong - let me know.

[ This Message was edited by: smoothie on 2002-06-21 14:25 ]

[Ants]

Nice diagram M8, yeah that looks spot on, holy cow i didn't realise the spring was so large, i thought it was smaller for some reason, that could explain why i cant compress the spring manually .

I'm gonna work on the 6 bolts tonight, (i need more penetrating oil).
When i eventually get the finned section off, is there anything i can clean it with, what dissolves exhaust carbon?? I have access to most chemicals in our lab.

Ants

[Rick MacLaren]

Exhaust carbon on the wastegate can be cleaned off using chemicals or gentle grinding.

I used a Dremel tool with sandpaper rolls on a rubber cylindrical piece, attached to the dremel. That allowed me to move it around inside, it had a flexible surface, and wouldn't take off too much. The rolls can be coarse, but ya have have to be careful not to take too much off the plunger. Don't worry too much about carbon in there. That's not an issue.

Smoothie is right. The big issue is often INSIDE the wastegate. The three bolts of which you speak can be removed but you've gotta get the right wrenches, 6 point, not 12, and use heat and/or WD40 and soak for a week. Use leverage on the wrenches and a vice. Don't vice the aluminum portion, just the strong exhaust flange.

The BIG issue is the SIX (6) ones that allow you to remove the cap of the wastegate. That'll allow you to inspect

1. Walls of the aluminum cap for spring wear
2. Spring for crosswise stretch
3. Floor of the wastegate for aluminum-baked powder.
4. Rubber boot for tears.

If there are no tears in the boot, and if the wear into the walls isn't too bad, your wastegate is ok. Smoothie's hypothesis is that it's baffed, and sticking or leaking, so you'd be best to get that area first and make sure you've got those interior pieces UP to par. Then move on to diagnose other parts elsewhere.

Nice diagram.

[ This Message was edited by: Rick MacLaren on 2002-06-21 23:27 ]

[Ants]

Yeah i have a dremmel, just wanted to soak it cos i'm lazy

Can anyone tell me how to remove the front valance, i'm getting some ramps tonight so i can also check out the rubber boot under the fuel distribution.

Ants

[ This Message was edited by: Ants on 2002-06-21 23:40 ]

[Rick MacLaren]

Wow. You're removing the front valence to get at that booty? You've got more guts than me. Or is the Euro model different somehow?

I got at it from the top on my US model. It's a bit hard on the back, but if you get all things cleared away from the top, you can stretch down there, rest your light, peer into the turbo area and unscrew the clamp thingy pretty easily.

The spot to look for is UNDERNEATH the 90 degree elbow...that's where it'll crack. Heat builds up there and the rubber will deteriorate.

OOoooooh! So you're putting it on RAMPS to see it from underneath? Well you should be able to just remove that floor pan without removing the front valence. A mirror should work ok too to see under the 90 degree booty.


[ This Message was edited by: Rick MacLaren on 2002-06-22 00:03 ]

[Smoothie]

There's a small diagram of a wastegate on page 25-22 of the Fuel System section in the 924 Turbo factory workshop manual. I'd scan it in if I could, but I can't right now.

[Ants]

Yeah i remember scratching the valance on the gradient of the ramps last time so i thought it would be easier to remove it, i could clean up the oil radiator and try and get the air horn thingy to work (got a crap VW golf horn at the mo, sound like a gnats chuff
Smoothie that would be great if you can do it, let me know and i'll give ya me email.

_________________
1980 931 Euro spec, "you know the one with the power, without repeaters or those daft bumper extensions."

[ This Message was edited by: Ants on 2002-06-22 01:21 ]

[Smoothie]

The diagram in the manual won't be any more useful to you in disassembling/reassembling than the one I made - it just looks a little more like the real thing. I can't say when I'll be able to do any scanning. Looks like that old computer booted up for the last time a few days ago. I'll just replace the processor/motherboard/memory and power supply. It doesn't owe me anything - a Pentium 200-MMX - well past time for an upgrade anyway... When I get a round tuit, I'll go through the tangle of wires behind there and see about attaching my scsi devices to the laptop.

[Ants]

Yarghh computers, i used to be a PC engineer, i still build my own and know what a pain they can be , thats why i opted for a life of orthopaedics, the human body is so much more predictable LOL

BTW i think i'll have to leave the valance, i discovered it is the 944 that has a plastic removeable one, this metal one is a bit more integral, oh and got some shiny new ramps to play with in the morning

[Smoothie]

I used to use ramps, but never put my full trust in them - always filled in the empty space beneath them with wood or bricks in case they ever wanted to flatten out on me. I always use a jack and jackstands now, parking brake on, wheels chocked and just in case of the worst, also leave the jack positioned where it can be easily pumped up by the first good samaritan that walks by. I'm not at all paranoid though - I like to say "prudent".

Maybe a piece of wood or two to drive over at the bottoms of the ramps will keep your valance from hitting them.

[Rick MacLaren]

Yeah that's a good idea. Beats tearing the front end off with a cutting torch, eh?