924Board.org

Brian L. · Posted: Mon Jul 10, 2006 9:16 am Post subject: Vacume Advance

Trying to get my 1980 NA 924 back on the road after Ten years. Had some rough running. But after replacing all the vacuum hoses, flushing the fuel system, new fuel filter hod no improvement. Then replaced the Dist. Cap ,rotor and plugs (although they all looked like new)
and that seemed to cure the problem.
Now I need to reset my timing and here is my question: My two vacuum lines. One is the vacuums retard and that works just fine, But the Vacuum advance line that goes to my throttle body has no vacuums and when I disconnect the hose from the throttle body and manually apply vacuum (suck on the hose) there is no resistance. It just draws air right on through the diaphragm on the distributor. Unlike when I suck on the retard side (with the dist. Cap off) I can see the breaker plate rotate. It looks to me that I need a new distributor but why no vacuum in the line? Any help would be much appreciated.

Car history: 84,000 mi. My car was parked out on the street New Years. When I got up the next day found someone had run into it. Front passenger fender and door smashed. Parked in the back yard
for the next ten years. Last summer repaired a rusting battery tray and repainted the car, over the winter had the seats recovered, replaced the dash and all sorts of odds and ends. I’m getting close and getting anxious to get her on the road.
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1980 924 N.A. Monaco Blue owned since 1987
"Remember, sitting on your ass won't finish your project" -Puddins fab shop.

Ozzie · Posted: Mon Jul 10, 2006 11:46 am Post subject:

Had a similar thing happen to me. Got another dist.
Not sure if the diaphragm section is available as a spare.
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Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Paul · Posted: Mon Jul 10, 2006 12:45 pm Post subject:

You will only get vacuum from the advance hose when the motor is under load.
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White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

CBass · Joined: 03 Nov 2002 Posts: 2807 Location: Vancouver, Canada

Anyone have a decent copy of a vacuum diagram? I'd like to make my decell valve functional again. Cracks and pops are kinda nice when you're flogging it on a mountain road, but they get funny looks from cops in the suburbs

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'81 931 in various states of assembly

Brian L. · Posted: Wed Jul 12, 2006 10:52 am Post subject:

Thank for the input guys. Gointo a all Porsche swap meet this Sat. in Seattle, maybe I will get lucky and find one.
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1980 924 N.A. Monaco Blue owned since 1987
"Remember, sitting on your ass won't finish your project" -Puddins fab shop.