Allis B carb question?
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Topic: Allis B carb question?
Posted By: Dave Everett
Subject: Allis B carb question?
Date Posted: 06 Nov 2011 at 4:46am
| A question? Allis B Zenith cab has a fixed main jet No 18 but this one only runs on half choke, If i change the complete carb it runs fine. My question is this, If i were to put in a larger, say size 24 main jet, and an adjustable needle, as fitted to a WC, would i be able to adjust the fuel down enough to allow it to run correctly ? |
Replies:
Posted By: Jeff Z. NY
Date Posted: 06 Nov 2011 at 5:14am
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Don't know.
If you are going to try to modify the bad carburetor tt probably won't run right when you get down because it sounds like it has a gas flow restriction in it somewhere and will still be starving the engine of gas evem with a bigger jet. ------------- I Love Meatballs and Dumplings on Toast with Gravy and Rosemary and ??? {Open For Suggestions} |
Posted By: Dick L
Date Posted: 06 Nov 2011 at 7:15am
| You can adjust the fuel jet down to nothing. The problem will be in the venturi. The venturi is what causes the proper vacuum to draw the the fuel into the engine at the proper mixture. The larger hole in the venturi will have a lower vacuum in the smaller engine. You would be able to make it run. It would not be at the best power setting without matching the venturi to your engines air flow. |
Posted By: steve(ill)
Date Posted: 06 Nov 2011 at 8:47am
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I think he is saying one carb works good, the other only runs at 1/2 choke. He is talking about putting a jet "like the WC" in the B carb, not installing a WC carb on the B.. DAve, im guessing the old carb worked at one time ? Assuming that, i would say the carb has crud inside one of the ports after the main jet. I doubt you need a bigger jet, im thinking you need to remove the jet, poke wire down the ports or boil it out, etc. I soak them in laquer thinner, then blow out with air. Wire down the ports is good on some to get them clean. Like Dick said, look at your venturi and make sure it was not bored out oversize.. ------------- Like them all, but love the "B"s. |
Posted By: Bill Long
Date Posted: 06 Nov 2011 at 9:34am
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There are two very small jets at the bottom of the carb. They have to be cleaned to get a good. I remember Pop taking the carb apart on a newspaper and using a very fine parts wire to clean those jets. Worked. Hope it may be a part of your problem. Can't have my favorite not running right. Good Luck! Bill Long |
Posted By: orangeman
Date Posted: 06 Nov 2011 at 9:44am
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Hello Dave: I would recommend you take the B carb apart, seperate the air half from the fuel half. Get a crushed tomato can or something that size that can accomodate one half of at a time, fill it up with simple green or similar non toxic cleaner. Fire up your wood stove and place the carb soaking in the simple green in the can and boil it for a while. You have nothing to lose and may be able to dislodged the gunk in the tiny ports in the bottom of the carb. Reassembly and fire up. Good Luck Hope this helps! Orangeman
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Posted By: Steve K
Date Posted: 06 Nov 2011 at 10:22am
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I would get some carb cleaner at NAPA. Remove all the jets and soak the carb for a day. The cleaner is made for carb cleaning and works better than a degreaser like Simple Green.
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Posted By: Jeff Z. NY
Date Posted: 06 Nov 2011 at 10:52am
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The way that metal get's with moisture and corrosion you could soak it for a year and it still would be plugged.
Carb cleaner does not break that down. Been there. Manual cleaning is the answer. Wire and high pressure air to clean out what you break free. You'll probably find out it's corrosion. A passage probably looks like the inside of a cast iron pipe that has hard water running through it for 10 years.  ------------- I Love Meatballs and Dumplings on Toast with Gravy and Rosemary and ??? {Open For Suggestions} |
Posted By: Dick L
Date Posted: 06 Nov 2011 at 11:28am
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I have been cleaning carburetors off and on for the last week. I just took this picture and I am on number six. I put about half or slightly more than half the amount of liquid laundry detergent that is used for one load into a two quart pan. Then fill with hot water and turn the hot plate on high. I boil for a half hour or more. I then remove the small parts such as the jets, discharge tubes and such. I then scrape, wire wheel and dig what has not boiled off. I do some times glass bead blast if I take it to the factory but not always. I then drop the parts into the carburetor cleaner basket and soak for over night most of the time but a few hours will do a good job. I then rinse with water and blow dry with compressed air. check for any left behind dirt and reassemble. Buying a gallon of carburetor cleaner with a basket is a good investment. Boiling the carburetor and parts will make disassembly easier and save the carburetor cleaner investment. Boiling the oil out of the dirt on and in the carburetor will make the carburetor cleaner last much longer.  That is probly a six quart pan. It holds more than the gallon plus cleaner can.
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Posted By: Steve in NJ
Date Posted: 07 Nov 2011 at 7:32am
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Dave,
Rebuild the carb that came on it. Probably is full of crud over the years. This way the air/fuel mix is correct. You don't want to mix match internal parts with those little carbs. They need to stay in their stochometric air/fuel mix as Dick mentioned about the venturi...
mailto:Steve@B&B - Steve@B&B
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Posted By: LeonR2013
Date Posted: 09 Jan 2020 at 7:33pm
| Sometimes when they set for a long time with water in them they get a gray corrosion in them that I've had carb. cleaner not touch after several days. I don't know how it does it, but soak it in used oil for a couple of days, then take it out and put it in your carb. cleaner and then another day in that and wash it off with hot water. Surprising what it does. I also think for the rust etc. electrolysis with baking soda might be the way to go. Leon |
Posted By: ac fleet
Date Posted: 10 Jan 2020 at 11:22am
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This thread is dated 07 Nov. 2011. ------------- http://machinebuildersnetwork.com/ |
Posted By: Ted J
Date Posted: 11 Jan 2020 at 12:24am
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Leon, you just come back from a trip to Colorado or Illinois? ------------- "Allis-Express" 19?? WC / 1941 C / 1952 CA / 1956 WD45 / 1957 WD45 / 1958 D-17 |
Posted By: chaskaduo
Date Posted: 11 Jan 2020 at 8:22am
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Interesting info on the grey corrosion with the oil and carb cleaner approach. ------------- 1938 B, 79 Dynamark 11/36 6spd, 95 Weed-Eater 16hp, 2010 Bolens 14hp |