Hi all, time for another stupid question...

I adjusted my idle last night (and no, i don't mean that i finally got off the sofa to do something to my car), and when i went to put the filter housing back on i found that i had one end of a rubbery pipe loose - i don't know what it's for or where it was going before.

It is about the same diameter as a pencil and comes from the top of the manifold (right of centre)

When i first noticed it it, the other end was tucked down near the back of the carb but wasn't attached to anything.

I looked thru my Haynes manual to no avail although i did find a description of a diagram which did not appear to match the actual diagram - could it be a 'gas sampling pipe' and would i have one on a 1990 1275 Rover Cooper?

(NB: engine is a replacement one so this may not even match specific knowledge of my exact model!)

I took a pic last night but didn't get around to uploading it anywhere - will upload tonight if not resolved by then...

Cheers, Steven.

PS I took the car for a run after and was very happy with how it was running and the idle and everything so i guess it can't be all that crucial but i'm just curious...why does my car have so many unnecessary pipes and wires that don't connect to anything???

It's not your vacuum advance hose is it? It'd need to be long enough to reach your distributor..

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Gareth.

I dunno, i don't think that the pipe was all that long, so maybe not.

so you've got a '90 rover cooper with twin SU's on it, right... not injected?

a hose coming off the inlet manifold should always be connected to something, otherwise the motor will be sucking air in through it - that's called a "vacuum leak", and it sounds like you've got a big one!

if your idle was racing, then that hose not being connected to anything would be the reason why - the motor is sucking air through that hose, instead of through the carbs. Put it up to your ear with the motor running.... block it with your finger and notice the difference, if you've slowed your idle down with the carb screws, the motor will probably die because it's not getting air anymore

normally it'd be for a brake booster - being a late rover, you'd have a booster, is there a hose missing from that? have you noticed your brakes aren't as light/good/responsive as they were?

if it's open, and doesn't go anywhere, cut it short, and silastic a bolt or something into it to block it.... or post a picture of your engine bay and we can play "spot the missing hose connection"

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did I tell you that I won a trophy?

ahh, good one, could have been a short rubber hose connecting to a longer plastic hose

I haven't had vacuum advance for years, so forgot about that

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did I tell you that I won a trophy?

If it has automatic choke, it probably goes to a black box about the size of a matchbox on the firewall, somewhere between the brake booster and the carbs. (Assuming twin carb uses same choke stuff as SPi).

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1970 Mini Deluxe - 1275, Weber, Clive 346 cam, MS 4-pot slotted discs, Megajolt ignition Now with new improved Mambas... almost on the road
1966 Van with Traveller rear seat conversion
2008 Prado GXL
All in various states of repair...

OK - Thanks for all responses so far - here's my understanding

1) It's not a twin SU - just looks like this pic (from rsp-cooper-register website)

(a shame the pic's not bigger else i might be able to see if it's on that car!!)

EDIT: added pic of my engine - pipe comes from behind oil cap and goes ...where?:


bigger:
http://www.weevel.com/photos/ausmini/IMG_2743.jpg

The car is a 1990 Cooper RSP which came with a 1275 metro engine with carb, as i said though, the engine's been replaced so i don't know it's actual origins other than it's also a 1275 single carb

2) Not automatic choke

3) The idle wasn't racing it was too lumpy and close to stalling, so it just needed a little turn to get it idling a touch faster (it's now just under 1000 rpm, although the haynes manual reckons it should be 900 but at 900 it seemed too close to conking out).

I'll be home within the hour and get a picture up and i'll also check the length and whether there's any difference when i block the end.

Thanks again for your suggestions, you guys rock...

it looks to big for the vac unit, check underneath the air cleaner or on the computer, you cannot see the nipple on the computer and will need to unbolt it to see it.

I have a late model mannual if you get stuck (not in book shelf so must be in garage)

Cheers

B

Looking at where that hose originates, it's almost certainly sucking manifold vacuum which means you're leaning out the mixture waaay too far. Not safe to drive the car like this, if you leave it too long you'll burn a hole in a valve or piston.

IIWY I'd block it up until you can find out where it goes.

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Simon

The adventures of an owner builder in the Tallarook Ranges

On the Midas which has a A+ and much the same setup that hose is the vacumm advance hose for the dissy

Jon

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Roundies and Clubbies(except vans) are both ugly that is why I have Midas and a van
1293 Mini Midas Bronze,1275 Clubman van

I have the exact same engine/setup and I had to blosk that up. I don't know what it's for but I also don't have the break booster. I say block it up, maybe give brickworx a yell and see what he says.

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Respect mine and I'll respect yours.

I agree with feral.. I don't know much about the later motors, but that does look like the right sort of hose for vac advance...

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Simon

The adventures of an owner builder in the Tallarook Ranges

Don't know the setup on these late motors at all, and am throwing a possible out that I've seen on other cars.......

Does it have a vacuum operated valve on the air filter that opens and closes to allow hot or cold air to be used for the intake, they usually have a thermo valve in the air filter housing (controlled by a bi-metal spring) to allow vacuum to open or close the flap.


Dicko

you are right

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Rover 214 atm ....

Cheers, Thank You, Danke Schon, etc.

Hi, i'm up in Brisbane for the weekend so I'll take a look when i get home tomorrow, sounds very feasible and would fit in with where i found the pipe sitting. I'll let you know how it looks on Monday!