Carb issues.

[Darrman]

I bought this Autolite 2100 carb off of ebay and broke it down and cleaned it up, rebuilt it with a kit, etc. Now that I can start the engine I am seeing some problems. I am still kinda new to carbs, so I am not sure what does what yet.
First problem is a leak out of the side of the carb from around where the main butterfly shaft passes through the body of the carb, this may do the carb in, because I cannot think of a fix.
Second, the carb appears to be sticking open, dumping way too much fuel. When the motor starts, it will start by sputtering to life, then speeding up gradually to a high rpm, till I shut it off. I dont have the tach hooked up yet. Last night I couldnt get it to catch, but had flaming gas coming out the header, not good!
Can anybody give me some tips to fix these problems, Thanks!

[olgreen69]

Well I talked to the "old guy" in my shop about your problem. He says the butterfly rod, and or bushing/ seal is just worn out. And if the rod and bushing are worn out that could cause the butterfly to stick open. Is there any free play in the rod.

[willowbilly3]

The shaft bushings may be worn but you have another issue here. It is sounds like it is dumping fuel. Maybe you got the float level too high or something amiss in the needle valve. It is fairly easy to pull the top of the carb without removing it from the engine.

[Darrman]

I did pull the carb off, and broke it all back down to do some double checking. I am also thinking its a flooding problem, but found nothing wrong after carefully inspecting and making sure everything is ok. As for the gas leak, it is coming out the side, but the shaft just passes through the carb body, no seal or bearing. What I am thinking is that the carb is dumping so much fuel its sitting on the butterfly and being forced out the side by sheer volume.
The only thing I found odd is that according to the original diagram and the diagram that came with the rebuild kit, is that the shutoff needle is supposed to have a small washer at the top of the needle, right under the little clip that holds it to the float. I do not have anything like that on the new stuff or the old stuff, and neither does the original carb that came with the truck. I am wondering if this would cause the needle to not sit right and let it flood the bowl out?

[willowbilly3]

There is no washer there. Just curious, do you have the little bail wire from the float clipped down over the brass needle seat?

[Darrman]

Yes I do, double checked that one, .
Ok, I think I may have found the issue here, I have reassembled the carb except for the top plate, and set it level on a countertop, and filled the bowl with fuel to check the float. However before I could even finish filling it, gas was pouring out of the bottom of the carb at a rate of a drip every couple seconds. I am no expert but I cant see this being right. I am not touching the carb when its doing this, and when I move the butterfly its sprays like its supposed to.
Unfortunatly I can tell yet where exactly its coming from.
Any ideas?

[Thunderfoot]

Yes I do, double checked that one, .
Ok, I think I may have found the issue here, I have reassembled the carb except for the top plate, and set it level on a countertop, and filled the bowl with fuel to check the float. However before I could even finish filling it, gas was pouring out of the bottom of the carb at a rate of a drip every couple seconds. I am no expert but I cant see this being right. I am not touching the carb when its doing this, and when I move the butterfly its sprays like its supposed to.
Unfortunatly I can tell yet where exactly its coming from.
Any ideas?

Check the power valve or the gasket for the power valve on the bottom of the carb for this leak.

[willowbilly3]

Yes I do, double checked that one, .
Ok, I think I may have found the issue here, I have reassembled the carb except for the top plate, and set it level on a countertop, and filled the bowl with fuel to check the float. However before I could even finish filling it, gas was pouring out of the bottom of the carb at a rate of a drip every couple seconds. I am no expert but I cant see this being right. I am not touching the carb when its doing this, and when I move the butterfly its sprays like its supposed to.
Unfortunatly I can tell yet where exactly its coming from.
Any ideas?

Check the power valve or the gasket for the power valve on the bottom of the carb for this leak.

I agree. Check the accelerator pump housing too, they are prone to drip. Sometimes the cover gets warped over time, maybe from overtightening the screws. I have lapped them down with a sheet of fine emery or body shop sand paper. Use at least a 600 grit or finer and a real flat surface, like a pane of glass. You will see right off if it has high spots.

[71PA_Highboy]

OK,

This is probably gonna be longer and more involved than you were looking for, but I just replaced the 2100 on my Bronco, and I am fairly well versed on these.

First - are you SURE it is the right 2100? Check the number cast in the side of the main bowl .. sometimes it isn't easy to read. What size engine do you have and what is the casting number? (it is usually hidden behind the accelerator pump linkage)
Second, if the cross shaft has play quit wasting your time. All that you are going to do is introduce vacuum leaks.
Third - Manual or Auto choke?
Fourth, Yep- fix the leak first. Power valve, PV cover gasket and accelerator pump are all the most likely suspects. That said, I have had problems with porous castings before, where over time the flaws in the casting cause both vacuum and fuel leaks.
Fifth, if you are gonna get into carbs, buy yourself a 'Harley IV Bottle'. They are mini fuel tanks that look like IV bottles that will allow you to apply fuel to the carb using gravity. It helps for adjusting the float, can be used on the vehicle for testing on the engine, and it looks cool...

Good luck and let us know what you find.

Regards,

Eric

[Darrman]

Ok, turns out the power valve gasket was the main leak, had to switch gaskets out to get it to stop but finally it did. However I am still leaking a bit, very slow. I set it on newspaper with the bowl half filled and now there is a wet spot. I cant tell yet where exactly its coming from. I have it propped up on a socket so it will drip straight or somewhat straight down, so I can tell.
As for the carb itself, it came off of a 360, now its on my 390.

[Darrman]

Well it looks like I spoke too soon, about 30 minutes later the carb was leaking as bad as before. Seems like it takes awhile to soak through the gasket, but then pours afterward. I am real close to chunking this pos in the trash and buying a new one

[OldGuy]

You might find helpful information here:

http://www.hurtle.com/cars/mustang/fixes/carb/

http://www.carburetor.ca/carbs/tech/Ford/2-barrel.html

[jdricha5]

Well it looks like I spoke too soon, about 30 minutes later the carb was leaking as bad as before. Seems like it takes awhile to soak through the gasket, but then pours afterward. I am real close to chunking this pos in the trash and buying a new one

I just got a remamufactured one for 130 bucks from advanced auto parts and its work perfect for me!

[willowbilly3]

Well it looks like I spoke too soon, about 30 minutes later the carb was leaking as bad as before. Seems like it takes awhile to soak through the gasket, but then pours afterward. I am real close to chunking this pos in the trash and buying a new one

I just got a remamufactured one for 130 bucks from advanced auto parts and its work perfect for me!

Maybe they have got better, I quit buying over the counter remans about 16 years ago, I can't remember ever getting one that looked and functioned satisfactory.