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bobbber · Posted: Tue Nov 23, 2004 11:42 am Post subject: Distributor Vacuum Disc

Guys,

There's a small tube from the intake manifold, which does to a "disc" shaped object on the side of the distributor.

My understanding of this is - the engine pulls air through this tube which advances and retards the timing based on the amount of "suck"... is this correct?

Now, I used to have a bad 'ticking' coming from the engine, and I've recently replaced the inlet manifold - the ticking's gone.

If the tube had come off of the distributor (I don't think it was on there when I first removed it) - could this have caused the 'ticking'????
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Fiat Bravo 165 Sport

bobbber · Posted: Wed Dec 08, 2004 2:20 pm Post subject:

Anyone?
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Fiat Bravo 165 Sport

tvatavuk · Posted: Wed Dec 08, 2004 3:20 pm Post subject:

As you mentioned disc is there to adjust timing, and it needs vacum to work.
Was that reason for ticking ,obviously no one knows.
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Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

Eddie W · Posted: Fri Dec 10, 2004 9:14 pm Post subject:

In a word, no. The vacuum advance is a fuel economy measure really and simply advances the ignition timing when you lift off the loud pedal.The "disc" contains a diaphragm which the vacuum acts on . Of course with the hose disconnected you will be sucking air which doesn't help the running. There is only one take off for this which is on the left rear barrel, make sure you connect to the right place.
Regards Eddie
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