6 replies to this topic

[mini-clive]

My car was recently running very poorly indeed. I realised that the distributer vacuum tube had come out both ends. Slipped it back in, problem virtually solved however the revs were still dancing ever so slightly so I checked the tube and that was fine. The little rubber connecter that links the tube to the distributer has a tiny hole in it.

What is this part called and why is there a vacuum on a distributer?
I presume so there is no air resistance for the arm...?

Thank you

[mini-clive]

PLease?

[chrisandsarah]

I had a similar issue a year or so ago. The part is called a vaccum breather pipe advance and retard pipe/hose i think.

As for the issue, your vaccum pump might be shagged, pull the tube off the carb, suck on it and see if there is a vaccum, if not u might need a new unit.... but if there is a hole in the pipe replace it !!!!!

Im only 50% sure..... someone correct me if im wrong

Here is the hose on eBay (linky)

Edited by chrisandsarah, 05 September 2010 - 06:46 PM.

[Ethel]

Petrol engines have a throttle to restrict the air entering the engine if you need less than full power. You still need the correct fuel/air ratio to avoid the fuel self igniting or burning too hot in surplus oxygen so you can't just inject less fuel like you would with a compression ignition diesel.

When the engine is throttled, the cylinders aren't as full; reduced pressure in the combustion chamber means the petrol takes longer to burn. To optimise the timing of the igniting of the fuel to get the maximum power out of each power stroke the reduced pressure in the inlet manifold, behind the the throttle disc, is used to pull on a diaphragm on the distributor that in turn turns the distributor baseplate to advance the ignition timing to the fuel is ignited earlier to compensate for the slower, part throttle, burn.

[Stevie W]

Also helps with part throttle/cruising economy by keeping the ignition advanced!

[mini-clive]

Brilliant stuff thanks guys.

Now the part i need is the little elbow rubber joining
http://www.minispare...=...6449&title=

However this (once p&p is added) comes to over £5 so being a tight arse I was wondering where else i could get the part for cheeper. I've tries Minisport too by the way.

Ooh i've done a temporary fix and put some superglue over the hole...any problems with that?

Thanks again!

[Ethel]

You might find 'em in a local motor factors/accessory shop, any bit of hose that doesn't easily compress will do.