606 or 660 carb rebuild

I decided to finish my carb overhaul before tearing apart the hydraulics. I previously put in a new needle valve and seat a few months ago.

This time I soaked it overnght in parts cleaner and blew out all the passages. I took the old broken off metering nozzle out with an easy out and put a new one in even though it seemed to run all right with the broken one. I reset the float to 1 5/16". I must have had it set a little deeper before about 1 1/2" but it ran ok then. The new shut off solenoid that comes out of the bottom of the bowl came in Sat. but it didn't have an adjusting screw so I didn't pick it up.

Anyway, when I put the new needle and seat in this fall, I adjusted the float by pushing on the needle into the seat. It stuck a time or two on the bench but it ran ok during the fall. After readjusting the float today (using a screw driver) the needle was sticking some inside the seat or at least it wasn't let any gas in. I installed the carb two times on the tractor while taking it apart one more time, and it won't allow any fuel into bowl period, even when I beat on it.

The needle has a black tip on it. Is there something I can do with it or should I just order new ones and be careful with them. There is also this tab on the float that stops it from dropping down to far. How far down should it be allowed to drop? It just dawned on me that maybe I put the float upside down. Should that tab be up against the needle? Right now it rests on the back side of the seat.

Next question is that this tractor is close to a 606 industrial. I have no ID number and never have officially figured out what it is or what engine it has. Everything like the carb has a model number that says retired or doesn't match to anything. The ID of the throttle throat above the venture where the butterfly is measures 1 3/8" although the parts guys calls it a 1 1/4" carb. Some of the inside parts all seem to be the same though. The I & T IH-25 book states the 560 & 660 gas has a 1 3/8" carb on a C-263 engine. Does this sound right? I can't even get the engine block numbers to show up on any parts supply computers. The carb number is 388296R92.

Finally, that fuel shutoff solenoid, the old one there now has an adjusting screw that just freewheeled. The electrical part of it has long since been taken off. When the new one I ordered didn't have the adjusting screw I left it. The parts diagrams now seem to show a fuel adjusting screw with packing nut and packing. The diagrams show a choice of two. Anyone have an idea on that? I want a working adjusting screw as that may be part of my problem of not getting enough fuel. The book says to make sure it is open about 6 turns. But the parts guys say you don't need an adjustment, just allow the solenoid to open and close it. What is your opinion on that?

I cut the end off the old one with a hack saw and found the adjusting screw where it screws in, the round nut was basically broke loose from the housing. I J B welded the nut in this evening and plan to put it back together with a clamp holding the solenoid housing together. I don't know if it will work but I need to order something new for it if I can figure out what. I may just bullplug it if I have to.

I will still order a new seat and needle for it. The cut up shut off solenoid and adjusting needle valve will work but I will order a new adjusting needle for it.

However, I am still trying to determine which carb it is. Can someone confirm whether a IH 1 3/8" carb will have a 1 3/8" diameter in the throttle butterfly throat? The parts guy that looked at it on Sat. called it an 1 1/4" but he didn't measure it. The carb seems to match the carbs found under the 706 and 806 models. I measured the throat diameter inside the carb and it is a 1/32 under 1 1/2"

I now suspect I have a 2606 with a gas engine. The parts book states it has a diesel but there is an occasional mention of gas parts that suggests to me a limited number of 2606's were made with gas engines. I just wish I could match up the engine casting number with something to tell me what size it is. A C-263 maybe?