flooding and over reving 1.3 sr (second choke?)

[mk3 vinny]

Had a bit of a strange one last night the temp was about -1, went to take the other half home and the car was doing its usual running abit lumpyand not ticking over till it warms up, but this time i got 5 mins down the road and the car cut out like it was out of fuel, so it tryed to re-start it and after 5-6 attempts, it fired up but was reving at 4k then cut out again so i put some new fuel in then fired it up, and it was doing the same so managed to get it going and went down the duel carage way and seemed fine, till i took my foot off the throttle and it carryied on going, so i dipped the clutch and it reved up to 4k+, after i got about 10 mile the car was fine and also on the way back.

Then today i tryed to put the car on the ramps in the lane to diagnose a dead fuel gauge and got to the top just had to hit the stop's and the car cut out and wouldn't re-start, smelling like it was flooded so got the car started evensualy, and it was missfiring also reving up like last night. The way to drop the revs is to hit the throttle to the floor and release it.

I was thinking it might be the second choke sticking open would i be right and how can i sort it

Thanks in advance
Vinny

[marc69]

It's your automatic choke that's sticking, the 2nd barrel has a lever that won't let it open unless your foot is flat. I removed this thinking it would open more freely.....as soon as the vacuum opened it the car revs went way past the red line with my foot removed and I had to switch it off immediately so god know how I never bent a valve.

You'll need to check the auto choke mechanism and al the springs etc round it. Also when the car is warm, make sure the pipes to and from it are both hot. Also make sure all vacuum pipes are connected and the there are no wires or anythiing in the way of letting both the throttle and choke return to where they should.

[conza123]

i had same problem with my sr. i spent £250 on a new weber replacement carb that has a manual choke

[craig green]

Whats most likely is it's carb icing.
A symptom suffered by older cars on carburretors. The inlet air freezes in the carb body. In my experience it didnt thaw out like you would expect it to (sitting in a warm engine bay). I've heard of different issues but my old 1.2 wouldnt idle when it happened, but started & drove fine with quick gear changes.

search carb icing. Many an old thread about it, though fuel injection is so common among members now.

[mk3 vinny]

thanks for the help lads

mark69 yes the pipes are both hot and one of the vacuum things on the back is broken but it still works some how

conza123 i have looked in to them as im a big weber fan but i dont have the cash

craig green i will look in to iceing i thought it might be that as well but dissmissed that as i thought it was impossible as the engine was hot.

[marc69]

The vacuum on the back is for the choke idle so that will need replacing, it also afffects the vacuum for the second barrel butterfly.

[Dave A]

I have had very similar issues to this. It was down to the second choke not fully closing, even open a little it will fire the revs way up. Mine was a tiny bit of dirt stuck on the butterfly stopping it shutting. But it could equally be something in the linkage or even the adjuster under the carb body.