What's this pipe ?

[al]

Hi guys,

So I was poking around in the engine bay today, trying to see where I'm going to have to fit replacement gear cables given that mine snapped on the way to the garage to get my MOT done the other day, and I noticed that there was a rubber hose (black, maybe 5-6mm OD) coming from the engine whose 90deg connector has perished and pretty much fallen off...

the tube itself is (or rather, should be) connected up at the top-back-right of the engine as you stand looking at it from the front of the car, and runs off along the back wall of the bay off to the right,

there's a little clip on what looks like another tube connector on the engine just to the left of where this tube connects.

So, after all that rambling, I guess my question is: what is this tube, does anyone know what the diameters of the connector ends need to be (so I can try to get a new one from somewhere - I didn't take it off yet because I'm sure it's going to disintegrate when I do ), and how bad is it for the engine running like this ?

ok, so that was three questions rather than one

cheers,
al.

[M100 TWO]

Al, it is a vacuum pipe which goes to the vacuum reservoir under the n/s plastic wheel lining which drives the heater control flaps you will require vacuum pipe which has a thicker wall than standard pipe, try Lotus spares
john ps if leaking the engine idle speed would be all over the place

[al]

Ah, nice one !

Thanks John

[John_W]

This same pipe was disconnected on my car. This means that the vacuum reservoir can't have been working and therefore that I haven't been able to switch the heater off for about what ten years. Just as well I live in Aberdeen then.

More strange is that the connection on the plenum has been sucking air for ten years and I haven't noticed any problems with idle speed. We'll see how it behaves when I finish the current tasks (cam belt, water pump, Samco hose replacement, brake service, etc).

John