Lots of pics I've seen of booster sets ups I can't see a 'non-return' valve in the vacuum hose, yet I read - all be it on sellers sites - that one is essential. Does every one have one or do you get by without?

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

The elbow /connection fitted to the bellows on the booster is the one way valve. It should be able to hold a charge after the engine has been turned off.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

They all have them. Like Mick said they are in the elbow fitting.

If you didn't have a non-return valve you would not have vacuum in the brakes when you opened the throttle!
Maximum vacuum is pulled when you are coasting along on closed throttle. So it stores the vacuum till you need it.

In some cases with some cars (though not usually with Minis) you can actually run out of vacuum depending on the cam and the way it is driven. XU1 Toranas had a double diaphram booster (a bigger capacity booster) and HO Falcons had a vacuum tank to store more vacuum. Ford made these vacuum tanks as an option for towing packs.

Gottcha - re-read the blurb at it says "essential if you don't have the U shaped connection"

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

I know three different valves: conecting directely to the manifold (Cooper S), valves in the middle of the hose (Rover standart from '89 on) and like Mick said.

Cheers,
Jan

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No speakers, no bodykits, no six-inch spacers, no spak filler, no bullshit