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nc30 pilot circuit
Posted: Tue Sep 18, 2012 10:35 pm
by lalalandrus
i have a rough idling nc30, it wont idle reliably under 2.5k and i am suspecting it is a pilot circuit problem. horrible low end torque and at times it seems like a misfire on one of the cylinders
i did notice i was missing a washers in all of the pilot circuits and was wondering if anyone has the sizes for the pilot circuit o-ring and washer
thanks
Re: nc30 pilot circuit
Posted: Wed Sep 19, 2012 12:04 am
by Cammo
It does sound like the pilot circuit is playing up. The best way to resolve it is by ultrasonic cleaning, unless you have access to a large tank you'll need to split the carbs (putting them back together isn't the most fun job in the world).
I've lost count of the number of carbs I've seen with blocked pilot circuits because they've been left sitting with fuel in that slowly evaporates.
I don't think the washers will be the solution to your issue, but best to fit some like you say.
Re: nc30 pilot circuit
Posted: Wed Sep 19, 2012 2:00 am
by lalalandrus
yes i think it might be a leak as well since i am missing those washers, sizes for the o-rings and washers would help me have all the parts ready before pulling the carbs out
Update : omg I think I found the oring sizes... 16075-KG8-9010 pilot screw o-ring CS1.2mm ID2.7mm. Just need the washers now

Re: nc30 pilot circuit
Posted: Wed Sep 19, 2012 7:48 am
by fatkid_loves_cake
Keihin airscrew washer part number 0301 803 2000, allensperformance stock them about 70p each, phil
Re: nc30 pilot circuit
Posted: Wed Sep 19, 2012 10:57 am
by Neosophist
are you sure the washers are missing?
many times they get stuck in the hole and you can hardly see them...
Re: nc30 pilot circuit
Posted: Wed Sep 19, 2012 5:07 pm
by lalalandrus
Yeah I looked in there. Plus the order should be spring washer then oring. All I got was spring and oring

Re: nc30 pilot circuit
Posted: Wed Sep 19, 2012 5:26 pm
by scotjell
HAHA I've just sent three of these washers out to another member on here as his were missing. Yeah a scriber or small screwdriver give it a wiggle and see if you can get them out. But good to know that these are available without having to buy the pilot screw spring O seal and washer as they are £16 a set.
Re: nc30 pilot circuit
Posted: Wed Sep 19, 2012 6:00 pm
by lalalandrus
you have any more to take a caliper to and measure

it is the shipping that kills me
Re: nc30 pilot circuit
Posted: Wed Sep 19, 2012 6:29 pm
by scotjell
Give speedy231278 a PM as at present they are in the post on their way to him.
Also he only needs 2 but sent him an extra one. So he may forward it on.
Re: nc30 pilot circuit
Posted: Wed Sep 19, 2012 6:40 pm
by speedy231278
Yeah, if there's a spare one I can post it or measure it, although as Lala says it's shipping that kills, maybe he's not in the UK? I'm pretty sure I read while searching for them that they are 5mm diameter with a 3mm hole, if that helps, but the thickness wasn't specified.