Webers pick up from cold

[checkrail]

Hi, Starting my +2 from cold I give it 2/3 pumps and it always starts 1st turn of the key, the problem is however careful I am with the throttle it will not keep running, it usually takes 3 goes on the starter before I can gently increase the revs and then it's fine.
I am on a normal mechanical fuel pump and no choke fitted, it will idle at approx 600 rpm stone cold and 900 when hot.

Any suggestions would be very welcome Thanks John

[alanr]

Mine would do exactly the same thing if I didn't use the choke to keep it running when stone cold.
I do exactly the same as you, also mechanical pump, and it starts immediately after a couple of accelerator pumps but then I use the choke to keep it running for a couple of minutes until it revs cleanly then push the choke in.
Suggest you reconnect the choke.

Alan.

[bitsobrits]

Hi, Starting my +2 from cold I give it 2/3 pumps and it always starts 1st turn of the key, the problem is however careful I am with the throttle it will not keep running, it usually takes 3 goes on the starter before I can gently increase the revs and then it's fine.
I am on a normal mechanical fuel pump and no choke fitted, it will idle at approx 600 rpm stone cold and 900 when hot.

Any suggestions would be very welcome Thanks John

Seems to me normal operation for a carbureted car when not using the choke.

We have become so spoiled by modern fuel injected machines.....

[elans3]

[/quote]Seems to me normal operation for a carbureted car when not using the choke.

We have become so spoiled by modern fuel injected machines.....[/quote]

Not normal for either of my Weber carburettored Twincams, (an S3 Elan and an Alfa 105 2 litre).
My Elan on 40 DCOE31's starts immediately on 2 pumps, and after 4/5 seconds of "tickling" will rev cleanly and idle at about 600 rpm after 10 seconds. When the thermostat opens the idle increases to 850 / 900 rpm.
The only mod to the Elan is an Aldon Ignitor (Pertronix) & has standard mechanical fuel pump.
The Alfa has a 123 distributor and an electric fuel pump.
I never have the choke cable connected on either, nor have I ever connected a DCOE choke cable in 45 years of having them on a myriad of different cars.
Sounds like you may have a slight air ingress leak somewhere, or might be a fine tune / balance issue.

[checkrail]

Thanks for all the replies, but I don't have a choke cable fitted. When I bought the car the cable was badly frayed and not usable.
If it's left longer than about three days I have the problem.

John

[richardcox_lotus]

Mine has always behaved the same if the carb chambers have been emptied. I ponder if it’s a result of the mechanical pump struggling at low revs to fill the chambers fast enough for it to be sucked through the cylinders in a low vacuum environment.

Just an opinion - no facts or science behind it !

Regard
Richard

[MrBonus]

I always enjoy reading these threads to see if my car is "normal" or not. My Elan is/was my first carb'd car.

I have an electric pump which I let prime for 10 - 15 seconds, then 2-4 pumps if it's warm outside and 6 - 8 if it's cold. No choke. It usually starts on the first turn but does require a little throttle assistance to idle for the first 10 or so seconds, then it will hold a roughish 600 RPM idle until the engine warms up, then it's fine.

[webbslinger]

MrBonus pretty much described how my car starts, although mine usually takes a few less pumps. The last time I used the choke was in 1989, just before I bought a new set of plugs. The choke knob got a free ride for 30 years until it was replaced last year with a battery kill switch. I hope the switch is as unneeded as the choke was.