disappointed with needle and seat in carb kit

Hi guys, I'm pretty sure that this has been discussed before but I am disappointed with the needle and seats in the carb kits that I have been getting. They seem to be all the same too. They all seem to leak. They all have a little needle with a little rubber tip. I'm sure there will be some master carburetor mechanic on here that swears that they never have a problem but I sure as hell don't think that they are any good. Maybe part of it is today's gasoline. I don't know. I put one in a Marvel Schebler carburetor today and the needle sat so deep in the seat that I could not use the float clip. I took the clip off and assembled the carb and the tractor ran good but sure enough when I shut it off the carb began to drip. Does anybody make the original style all metal needle. I think they actually work better. All the parts today are junk. It's sad.

An old carb man told me this trick and it does work. When putting in a rubber tipped needle you need to put a set in the rubber. To do that you drop the needle into the seat and tap on it a few times with a screw driver of some such thing

I was told by a mechanic that worked for a Massey dealer to throw the spring clip that hooks the needle to
the float away. I have had better luck doing that. I observed that the clip was hitting the seat and not
letting the needle seat.

Jim

I have seen that done with the all metal needle when a new one could not be found. I have a friend who went to a sale and bought a lot of old stock carburetor kits. He took the needle and seat out and used any that would fit as long as the seat would screw into the carburetor body

I will add to what Old said. Very often the seat is not good. Sometimes you
can even see it is oblong. At any rate, I have a tip from an injection
nozzle that has the proper angle for those seats and I insert the tip and tap
it with a hammer.

Then, I put the needle in and suck on the end of the threaded end. It should
pull the tongue in enough to hold the needle when inverting it and hold
indefinetly .

Yes , they are bad and have been for many many years.

On a side note, IH went to the viton tip needle in the 60 series tractors
because the larger fuel tanks apparently put enough pressure on the older
steel seats that the 4 & 560's were constantly getting dripping out of carb
complaints. The replacement needle and seat with viton tip did a real good
job of sealing them up. It was years later when the quality went to pot.

Did the new one match up in design and length with the original one you took out?

When you shut it off how long did you let it drip?

What you may be seeing is residual fuel clinging to the inside walls of the intake, especially in cool weather. When the engine is shut off, the gas comes running back down because the air flow that was suspending it has stopped.

Try leaving it the gas on a couple minutes and see if it will stop.

When I assemble a carburetor, I like to turn the top upside down and suck on the fuel fitting, then put my tongue over the hole. It should hold vacuum. If it doesn't, something is leaking. Not necessarily the needle valve. If the seat did not fully screw down on the gasket it will leak.

Did you test the float for gas inside a pontoon? You can give it the shake test or float it in water, see if it floats evenly.

And finally, most flooding conditions are caused by rust flakes or trash in the tank. The fuel must be clean, only takes a tiny speck to hols the needle valve open, a sliver of rust can damage the sealing surface. There should be a screen in the inlet fitting of the carb, a screen on top of the sediment bowl, and a screen standing upright inside the tank. All three need to be in place and the tank clean and not flaking rust. If the tank is flaking or dirty it will continue to have problems.

Inline filters are not good with gravity systems. If you want to use an inline filter, find a screen type, not a pleated paper, they clog quickly and are too restrictive.

One other thing I like to do, before making the final fuel line connection to the carb, turn the gas on, let the line flush while you make the connection. This is especially helpful if the area around the fitting is crusty with dirt and grease.

I've found on MS carbs the 1/4 inch spec most have for the float setting does not work. I set them to 5/16 and have had no trouble since setting that way.

Its a common problem with a many shade-tree tricks to defeat the issue... Its not unusual for the fix to be to install the old needle and seat...

I am building this one I could not get one of the seats out it may just stay in there... The last one like this I did the fix was to put the old needle and seats back in it...

I think a lot depends where they are made. Stan

I have had same problem, quality is just not what it once was.

Tire kicker, you are right this has been ongoing for years and has come up here a few times. It is on all MS carbs not just IH. Usually what you do is if it still has a brass needle you throw the new neoprene tipped one away. When you insert the neoprene tipped one you tap it in gently with the handle of your screwdriver as old said. Whatever you do if it has the clip to hold it to the float be sure to use it because the clip insures that it moves with the float.