MTFCA Forum

I am going to try to rebuild this carb.
Is it savable?
I currently have it sitting in a can of carb cleaner.
The brass bits seem to have been in for a long time.
Is there a better way to get these out to be replaced?
One more question, what size of tap and hex stud that is to be used to fill the channels once the brass has been removed?

What carb kit should I order?

That's an NH and it looks like you were able to buy it because the last guy or someone else in the past couldn't get the jet out. Application of red-hot heat and air cooling or dropping into water will usually be enough to loosen them, though about 25% need multiple applications of heat/cool. The jet will come out with the right tool, but that tool is not commercially available, so you're going to need patience and perseverance. If you have the ability to make a tool, you will need to hold it in a drill press and press DOWN HARD while unscrewing to make up for the loss of a defined slot. The float valve looks like it will present challenges as well.

With almost no doubt, the throttle shaft bushings in the casting will be wallowed out and need rebushing. Every part for an NH can be purchased from suppliers except for throttle shaft bushings...If you can make them and install them you will have a carb which will reliably idle at the same RPM day in and day out...without new bushings, the idle is going to bounce around some.

The passageways are barely under 1/8" in diameter and if drilled out carefully, can be replugged with 1/8" brass rod tapped into place. Start with a 1/16" drill after putting a centerpunch on the plug. Move up in size slowly through number drills, stopping at #31 (though the plug should spin out at a much smaller size, typically around #36 or so).

Per Scott "...can be replugged with 1/8" brass rod tapped into place.". I didn't have brass rod but I had a brass screw that fit.

Steve- yes, it is salvageable.

Trying to remove the jet or seat in these old carb bodies without a torch will only knacker up the brass slots as you have here. Dont bother, they wont come out. You will only destroy the slot & possibly make the parts unremovable.

Get out the blue wrench. With an oxidizing flame, heat the iron on both sides of where the thread is behind. Cherry red to orange.
Let it sit until cold, an hour or so. A little penetrating oil can be applied when cold. Usually not necessary.

Clamp in a vise. Select the appropriate sized screwdriver to fit. The blade must fit well & be sharp, like new. A hollow ground blade is best, but not required.
Turn clockwise(tighten) a bit. It should have turned easily. If there was no movement, a second torch session is required. Unscrew(counterclockwise) to easily remove. [Better than 95% of the time, one torch session does the job on the nastiest carb body.]

The idle circuit passage plugs should be opened & the jet & seat removed before soaking in carb cleaner.