Solex carb choke adjustment

BX Tech talk
User avatar
demag
BXpert
BXpert
Posts: 720
Joined: Wed Jan 09, 2008 7:04 pm
Location: West Midlands
x 1

Solex carb choke adjustment

Post by demag » Thu Apr 24, 2014 4:59 pm

I'm a bit stuffed here. I refurbed the carb with the service kit and it is dry now and the car drives quite well. However when I start the engine from cold it revs its nuts off. I can't find a reference anywhere to the fast idle speed but I should imagine about 14-1500rpm is adequate. The Tgs is pushing 18-2000rpm and seems to stay like that for a number of minutes before eventually slowing to a normal idle once it reaches temperature. I don't like revving cold engines like that and it can't be doing it any good. These Solex carbs all seem to have detail differences and the ones in Haynes all look slightly different to this one. I took great care when doing the carb not to alter any settings as it's such a stupidly complicated thing I didn't want to screw it altogether.

I haven't started it today as I've got the clocks hanging out checking the speedo cable. I have taken the air feed plastic cover off the carb though and the choke mechanism cover vacuum thingy off and can confirm the choke flap is in the fully closed position. Does anyone know how I can bring the revs down to a more sane level whilst on choke? I can feel a manual choke conversion coming on here quite soon if I can't sort this. A stupid thing but really annoying.
Dave.

2004 C5 Exclusive Estate 2.2hdi automatic.
1990 Bx TGS automatic.

User avatar
demag
BXpert
BXpert
Posts: 720
Joined: Wed Jan 09, 2008 7:04 pm
Location: West Midlands
x 1

Re: Solex carb choke adjustment

Post by demag » Thu Apr 24, 2014 6:14 pm

I think I might have found it. The primary choke valve adjuster screw (!) according to Haynes. It is conveniently placed in an upside down position on the choke mechanism in such a way that it can't be reached with a screwdriver. It didn't stop a pair of cranked pin nose pliers though! :lol: I had to dose it with WD40 to free it up and screwed it out 1/4 of a turn. I'll try and get the clocks back in tomorrow and try it. I'm pretty certain that is the correct screw as the arm it bears on directly operates the throttle on full choke. What an absolute pile of doggy poo!
Dave.

2004 C5 Exclusive Estate 2.2hdi automatic.
1990 Bx TGS automatic.

citronut
Over 2k
Posts: 2781
Joined: Wed Oct 31, 2007 7:55 am
Location: EAST SUSSEX UK

Re: Solex carb choke adjustment

Post by citronut » Thu Apr 24, 2014 8:49 pm

if you did not alter that screw whilst sorting the carb it should not need adjusting now,

if i recall is there on the side of the choke mechanism what looks like a miniature measuring calipers, with a screw at the pivot point, loosen the screw and adjust the gap of the two legs,

if you follow me

regards malcolm
curent ride
K reg BX 17TD TZD est
also own
K reg D special

no longer have
H reg CX saffari 2.5 TRI (now gone to Malaysia)
R reg xantia 1.9TD est (gone to meet its maker)

Tinkley
1K Away
1K Away
Posts: 1495
Joined: Sat Jun 06, 2009 11:27 am
Location: N Hants England
x 6

Re: Solex carb choke adjustment

Post by Tinkley » Mon Apr 28, 2014 9:38 am

I think 1700 is regarded as a correct figure, but I agree it seems and feels too high. The choke screw is the one affecting the little cam and points sort of upwards from the front facing part of the carb. The slot is accessed from underneath. I reset mine up with very low revs as it used so much fuel on the many short local runs I do. It still gets to run a bit high as it warms up but then drops down to somewhere normal.
You need to remove the 'back box' cover to get at it. The idle is accesssed from bulkhead side. Worth refurbing though? It definitely helped get better fuel consumption, I probably get 38 - 40 on just local runs with more on long stuff. Not too shabby for a 16, though I do use a 'soft' right pedal!. Too flaming expensive to do otherwise, though occassionally when well warm I let it go a bit.

User avatar
demag
BXpert
BXpert
Posts: 720
Joined: Wed Jan 09, 2008 7:04 pm
Location: West Midlands
x 1

Re: Solex carb choke adjustment

Post by demag » Tue Apr 29, 2014 7:43 pm

I got it all reset tonight. Fast tickover is 1500 rpm now but when it slowed down it was nearly stalling so I had to bring the normal tickover back up to compensate. It's amazing how all these settings affect each other.
Dave.

2004 C5 Exclusive Estate 2.2hdi automatic.
1990 Bx TGS automatic.