Morris Minor Owners Club

Hi not Minor but Mini related, although I'm confident someone will have an idea what is wrong.

Basically if you watch my video, the mixture control lever (operated by the choke) moves in, which causes the mixture control screw to fall off the side (see video).

The return spring on the mixture control lever works well enough, but weak enough to allow the sideways movement.

I'm struggling to find what is wrong.. my concern is the fast idler screw doesn't sit in the centre of mixture control lever.

When the choke is pulled wide open and the screw falls of the side, the two jam. This then means the choke remains open!

Your thoughts are much appreciated.

Anyway click the link for the video.... http://youtu.be/k_FZHX1eQKo

Dean
I follow your observations.A quck blast of the exterior, with carb cleaner won't go amiss...so that you can see everything
operating.Give the linkages and cables a squirt of oil ,so everything moves freely.

With a manual choke HIF.from the body of the carb outwards should be :-
1 cold start seal
2 cold start spindle
3 "O "ring
4 cold start body
5 spindle seal
6 end cover
7 retaining plate
8 two retaining screws
9 cold start spring
10 fast idle cam
11 tab washer
12 retaining nut
Your cold start spindle certainly " wobbles" as it comes off the adjusting nut and the spring looks to be weak ( ? ).
Does the spring( 9) look to be correctly located ?

if it is "unwound" by say half or even a full revolution, then it would appear to be "weak" compared to a correctly assembled one.

Is the retaining plate ( 7 ) secure, two screws fully tight ?

It not.. any slop in the system.. has probably worn/ distorted the various seals and " O " rings.Tighten the screws , if necessary and check operation

Any chance the throttle actuating lever has been bent slightly ? It looks fairly straight to me from the camera angle.
Is the adjusting screw at a right angle to the actuating lever or more at a different angle ?

Have another little play to see if you have any joy and give us any other information you have about the carb, e.g. working OK before, stripped and rebuilt from spare car,taken straight from another car and put on etc.

Bob
Bob

Hi Bob, thanks for the input. Much appreciate the time you took to post.

Firstly, I have only ever had the carb off once and this was when I reverted back to the standard exhaust set up. I bought it as a stage 1 big bore effect chav mobile. The choke has always worked ok, yesterday I went to start her and noticed the revs hadn't increased when the choke was pulled out, this made me have a mess and noticed the problem.

I am not aware of it ever being taken apart before. I think you are correct when you say the accelerator lever could be bent. I think who ever did the conversion originally and took the carb off may have damaged it somehow.

I have therefore, bent the accelerator lever back in line with the adjuster screw. The choke certainly seems to work a lot better now than before. Unfortunately if the choke has been operated the way it has for some time, I guess it could have done some damage.

I intend to take the car off the road November for a complete restoration.. so I guess a carb rebuild/clean/thorough examination will need to be included in the plans now.

Now to enjoy her before the MOT runs out.

Dean
Glad you sorted it.You can order individual items from http://www.sucarb.co.uk.So new washers, " O " rings,seals shouldn't cost too much ( fingers crossed ).The diagrams/hints/ tips on the website are quite good for a strip down.

A strip down, clean, inspection and fresh gaskets for a carb is never a bad thing.....might even improve the mpg !!
Don't start me on the cost of fuel.
Probably best to live with it for the moment, as you say.
Bob