NT carb issue

lgoodrow

New Member
Jun 30, 2014
1
0
0
lincoln
I have the 41 tooth sprocket, platinum plugs, demon expansion chamber, and new boost bottle
the Carb keeps acting up, first too much fuel then now not enough and hard to adjust. Any suggestions? I played with the pin position but did not change much, how can I get it back running again right?
 

2door

Moderator
Staff member
Sep 15, 2008
16,325
114
63
Littleton, Colorado
Welcome to the forum. I hope we can help you with your problem.

When you say, "carb keeps acting up" exactly what do you mean? Your problem might not be the carb or something easily fixed if it is.

Get rid of the boost bottle and make sure you have no air (vacuum) leaks in the intake circuit downstream of the carburetor. The NT carb is the simplest carburetor used on the Chinese 2 stroke, and in many's opinions, the best.

They really require little but clean fuel. Use an in-line filter ahead of the carb, set the 'C' clip at the second from the top groove and keep an eye on your spark plug color.
You didn't say what fuel/oil ratio you're using but if 16:1, change it to no more than 24:1


Tom
 
Last edited:

ckangaroo70

Active Member
May 13, 2011
862
116
43
Central Illinois
I have the 41 tooth sprocket, platinum plugs, demon expansion chamber, and new boost bottle
the Carb keeps acting up, first too much fuel then now not enough and hard to adjust. Any suggestions? I played with the pin position but did not change much, how can I get it back running again right?
I am going to assume you have checked your spark plug(scrap the stock plug in my opinion)...so the next thing I would try is to find an air leak in the system. I use starting fluid/ether to do this around intake connections/gaskets and welded joints. RPMs will increase if you spray near an air leak. Just be careful where you spray the stuff and go easy with it. Just a touch will tell you if you have a leak or not. May be getting some inconsistent or weak fire possibly due to failing mag, cdi, wire...loose plug cap. These little engine are really fairly simple construction and really just a matter of going through the fuel and electrical components and crossing each component off your list as it test good.
Could also just have a piece of gunk in the jet or perhaps a sticky float which will cause inconsistent fuel operation. Check the easiest stuff first.
 

ckangaroo70

Active Member
May 13, 2011
862
116
43
Central Illinois
My mistake...I missed the part where it says you are running a platinum plug. So you obviously are not running stock plug which is good. Forgot to mention... I would ditch the boost bottle. In my opinion those were the greatest money making gimmicks ever thought of. Wish I had thought of it, but have never seen where they actually work on anything. Never used one on a "Happy Time" engine, but have seen many tried on RC Truck, boat and airplane projects over the years and never saw where they made a bit of difference. Just another place to leak air in my opinion, but if you think it helps....then I won't argue it further.