The seat for the needle valve in this carb has an end with a square hole, and one with an open round hole. Which end goes up? Mine was square up.

The middle hole wasnt drilled through, and the first hole comes out that little hole on the engine side of the throttle plunger. There are 4 holes, the one for the choke you can see the choke plunger through.

 

Well, if the needle is square, then use the square side. If the needle is round, the round side. Never seen that before. The seats all have round holes. Why go thru the trouble to drill a square one?

4 holes you say? I don't know. I'd have to look. Any way you can post a pic?

 

Been meaning to post a pic, but camera hasnt been here. I took these with my cell.


holes.jpg?t=1244581081

Carb itself-

carb.jpg?t=1244581196

Just for the hell of it I taped off that hole, and tried to ride it. It revs nice but has no *****, and it stalls. Then it wont start again without some fancy kick starting and choke manipulation.

 

Man, I don't know for sure what that hole is. Like I said before, 3 holes, one for the idle, one for the choke, and the remaining has to be for mid-topend operation. Not sure why it would lead to the seat or why it would make such a huge difference if its plugged. Not sure why adjusting the needle does absolutely nothing either.

The best I can figure is your carb is WAY lean somehow. That would explain the backfiring. The plug is probably black because of all the choking you've done. Do you have any extra main jets? I was thinking of boring one really big and sticking it in just to see if you can get the needle working. Its possible that your main jet is so small that it doesn't matter what clip you have the needle. Also, if that hole leads to the bowl like you say, then plugging the hole would cause more gas to come up the needle jet (ie same as a bigger main jet with a non-plugged hole).

If you don't have any extra jets laying around, try running it without a main jet and see what happens. If it runs better, then try fooling with the needle clip. It won't rev out all the way because the mainjet is out, but it should work better. Enough to point you in the right direction.

 

I'm thinking of buying a jet kit just to play with it and see what happens. Any suggestions on one that would contain mains and air? Should you bump up a size with the DG exhuast? These jsts in here are stock according to the vault.

 

this should help you guys out:

people.morrisville.edu/~crovelp/Carburetor%20Theory.ppt

 

Man, I hate carbs. haha Its no wonder fuel injection is taking off! Although I'm sure that can lead to some problems too. I tend not to have as big of a problem with electrical issues though.

 

Which DG exhaust do you have? My girlfriends brother has a 230 with a DG RC exhaust that's a pain to get started. Although I don't think its the carb, although it will have to be adjusted once we get it to start.

 

Thanks for that article on the a-arm fix lt230sman. I wish I had time to do that right now and was willing to take my 230 out of commission for a while! I've been doing tons of riding lately!

 

The dg exhaust "should" require a bigger main jet. Nobody fools with the airjet. Just go to your dealer and grab a handful of jets from his collection. He shouldn't charge too much. Take your old one with you to match it up.

The airjet is just for refining that little bitty area of throttle between idle and barely open.