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View Full Version : Fitting manual choke to nikki carb



benherron
27-10-2009, 10:44 AM
Anyone have any ideas on how to route a choke cable to a nikki carb?
There's a fair bit of info on the nikki and mine seems to work fine, but there's little info on how to put a manual choke onto a beetle that originally didn't have a manual choke.
Adm I'm thinking I will have to route it down the passenger side of the tunnel, but not sure how to keep it in place.

Also where to get such a long choke cable/sleave?

Cheers ben

Big Birds Car
27-10-2009, 11:27 AM
No idea on fitting to the carb but "P" clips to secure the cable along it's length and you can get universal throttle/choke cables form many of the auto suppliers such as NF auto's for example. I got a long cable from evilbay, just types universal throttle cable and went through what was there. Alternatively how about a camper van cable? must be long enough.

Alzax3
27-10-2009, 06:35 PM
You can probably get a rear pushbike brake cable (or rear gear mech cable) that would reach - I've used those on mine before.

Spacenut
27-10-2009, 06:36 PM
It depends where you want to mount the choke control. Most people automatically assume it must be located on the dashboard somewhere, as this is convenient... for a front engine.

The Lamborghini Miura put the choke control on the centre tunnel, and I helped Giles Briggs fit a choke control on the top of the centre tunnel between the seats on his Nova. For this type of location a super-long choke cable isn't really required.

I seem to recall the Nikki choke flap has a strong spring return, so you could use a flexible braided cable inner (much nicer than the stiff wire type), which a control knob that locks in place with a quarter turn.

Fixed jet carbs such as Webers and Dellortos can normally be started by pumping the accelerator a few times before turning the engine over on the starter. This operates the accelerator pump jets which squirt neat fuel into the bores to overcome the momentary lean condition that occurs when you floor the throttle. I remember that the Nikki is a fixed jet carb, but if its the one I am thinking of its a progressive twin-choke where the secondary choke operates on vacuum demand. I'm sure it must have an accelerator pump though :confused1:

Lauren

Nic
29-10-2009, 04:20 PM
Could you use one of the heater box control levers? If you aren't going to use one of them that is.

benherron
29-10-2009, 06:56 PM
I very well could! Hmmm (idea explodes in head)..... I will definrely explore this when back home, I can't remeber where the cables came out at the back, but I should be able to route it easily enough. Thank you very much.

jimcub
30-10-2009, 11:05 PM
Mine had a Nikki carb on when I got it and with a choke on the dash, i sold both last year. But the choke cable measured about 15 ft and it ran down along the tunnel, through the rear bulk head and up round the fan housing. then a clip on the rear of the engine cover hole and back into the carb as the choke faced to the rear.
if I have any shots I'll hook them out for you.

benherron
30-10-2009, 11:44 PM
That would be ace if you did cheers. I can't find 15 ft choke cables anywhere but definitely like the idea of having the passenger side heater leaver put back on and used as choke, that hopefully would only need a 6ft cable which are a dime a dozon on eBay.
How did you find the nikki btw jim? I haven't got the mixture 100% right yet and was wondering if there was a correct way to do it other than slowly altering it as you go along? I assume the correct mixture would vary from engine to engine, but never having worked on a carb before I've no idea how to go about tuning it.

jimcub
30-10-2009, 11:55 PM
On mine it was c**p, as someone had played about with the arm on the second throttle; so it never opened.
The only useful bit was the glass float chamber which I found great, power was ok ish but I have twin webers now and they make all the difference.

Spacenut
31-10-2009, 06:48 PM
I had my Nikki on the HA Viva, with a 1256 Shove-it engine and a Vauxhall Nova aluminium intake manifold - can you believe they all fit together? A 1980's manifold on a 1970's version of a 1960's engine... :confused1:

Anyway, I called up a Nikki specialist (I can't remember the name now) and described what I had - and they supplied all the correct jets and a new fuel banjo to hook it all up. My little 1256 sang like a canary after that - my favourite pastime was sneaking up on sales reps in Sierras, they used to get really annoyed by being passed by an antique car. I did have to eat humble pie though, when I met an innocuous grey Anglebox - with Carlos Fandango at the wheel, I couldn't see it for dust!

That vacuum operated second choke (with the counterbalance weight) made a great noise!

Many fixed jet carbs such as Webers and Dellortos (and Holleys and Carters) will have a wide tolerance, so that a generalised setting will still give good results, particularly on a stock or mildly tuned engine. Fine tuning is really only possible on a rolling road.

Lauren