Choke Flaps

Post by **fume** » 14 May 2007 01:04 pm

Is the 1.4 weber carb supposed to have one or two choke flaps? All other carbs i have had experience of have only had one but the carb i have now seems to have had one removed, also the picture in the haynes manual seems to show the carb with two. Any ideas?.

Post by **IvanS.** » 14 May 2007 02:07 pm

1.4 have two choke flaps.
It could be removed to save fuel.
One is open if you go under 80-90 km/h and another one opens if you speed up to 100 km/h and above.
Then say goodbye to fuel.

Post by **Frits** » 14 May 2007 02:45 pm

It's normal. The weber is a two trap carb, wich says that under a certain "powerneed" Only one trap is used. With a cold engine you never use the second trap, so there was no need to mount a choke flap to the second trap.

(the 343's did had a second flap, but it is rubbish)

A flap is not good for the air flow.

Post by **fume** » 14 May 2007 02:50 pm

That makes sense if the 343 had one, i couldn't see any reason for a second flap, surely with the choke pulled out fully and both barrels closed it would use huge amounts of fuel!

Post by **IvanS.** » 14 May 2007 04:27 pm

Ouch... i didn't realise you're talking about diesel.
They do not have it. I see no reason why should they have it.
340 1.4 GL have two chokes, and it " eat gas for lunch '.

Post by **Frits** » 14 May 2007 04:49 pm

Diesel?

Post by **germ** » 14 May 2007 07:46 pm

what chokes we talking about?

choke chokes? for cold start up?

if so you can gain power/eficiancy from removing them but it makes em difficalt to start when cold

racing/rally cars that arent allowed different carbs/manifold change have chokes removed for extra 1-2hp

i know it makes a larger differnce on twin 40 solexes on the phh's 6hp on the dyno difference :S the car started up fine in the cold but you need to sit in it with throttel on a bit

i dont see why it would need 2 chokes unless it was set up for 2 as its only extra well choking.

Cheers
will-ps didnt know they made a 1.4 diesel

Post by **IvanS.** » 14 May 2007 11:47 pm

To frits : DL's here are mostly diesels, i forgot that they are not 1.4 litre

. Never seen an 343 working on benzine yet. Seen 345.

To germ : Diesel was available in some 340 and in 360 with 1.6 ( i also heard for 1.9 litre Renault engine )

Sorry for disinformation. My mistake

Post by **fume** » 15 May 2007 08:30 am

Yes i am talking about the flap connected to the manual choke cable. I am just curious whilst at the same time trying to cure a cold start problem. The car will start with the choke pulled fully out but will then cut out, i have to push the choke half in and blip the throttle to keep it running. Once it is warmed up it is fine and in fact goes really well.

Post by **pettaw** » 15 May 2007 10:17 pm

That's likely to be the pneumatic choke not working and using engine vacuum to open the choke flaps once the engine has started. Sounds like a carb rebuild is indicated.

Post by **fume** » 17 May 2007 08:34 am

Thanks for that, i have managed to get the car running better bit by bit since i picked it up by changing the usual suspects but this one problem remains, i will now look into either replacing or rebuilding the carb.

Post by **foggyjames** » 17 May 2007 08:28 pm

If you pull the choke out beyond halfway with Nessy's new engine (but the original carb), it refuses to start. Wierd...

cheers

James

Post by **fume** » 18 May 2007 10:36 am

Seemed to be a bit happier this morning, pulled choke out fully it fired then wanted to stall, pushed in half way did idle, a bit lumpy but did idle. It has had loads of redex and carb cleaner in it, so before i do anything to radical may just wait and see.

Post by **fume** » 04 Sep 2007 08:44 am

The car has now had a rebuilt carb fitted and setup, and also the fuel lines replaced. I couldn't stand the smell any longer!. I still have a problem though with it starting from cold. The new carb has transformed the way the car drives but it still won't run on choke without coughing and spluttering, I am wondering if it has a crack in the inlet manifold or similar that closes when the engines warms up and metal expands.
Any ideas?

Post by **Jason B** » 04 Sep 2007 12:37 pm

Stupid question probably, but is the idle speed raising sufficiently when the choke is fully out? if no then that could be why the engine stalls very quickly?

Not that I actually know much about carbs

Cheers

Jason