float level

MrTube

Well-known member
Ok I know this is a touchy subject but I need to bounce this off a few people.

I have a large K&N filter on the airmaze adapter on the stock zenith carb. Carb is a repro and is a few months old with an old float, the new float had a hole in it. Brattons sent a new float free of charge, I just have not bothered to install it as the original 80 year old float seems fine.

My issue is its running too rich even with the GAV closed. I think its too rich because even when its 30-40F I don't need to richen the mixture at all when the engine is first started, she runs great ice cold with the GAV closed completely (full clockwise). I also get some black smoke at times and it just stinks. Not enough time on the plugs to check them IMO.

I'm thinking I can lower the float level a tad which should lean it out. Will this work, and if so how much do I want to go?

I realize the filter will cause it to run richer then normal, However I am around 50 ft above sea level, I would assume the GAV should compensate enough when closed for this change, at least for the most part.
 
try adding another washer under the needle and seat. i have done this a number of times instead of bending the float.
my opinion on k&n filters are they collect and attract dirt from the oil on them.

you can have them even on modern cars. i throw them in the trash
 
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If someone replaced the needle housing or a new needle is possible its not closing off the passage way ? Some of the new needles are junk and bottom out before reaching the seat.

Ron
 
If someone replaced the needle housing or a new needle is possible its not closing off the passage way ? Some of the new needles are junk and bottom out before reaching the seat.

Ron

Hi Ron,

Its not leaking on the floor so I doubt it.
 
I suggest that you remove the filter to take it out of the equation. Then check the float level. Set the float level correctly if there is a problem. Proceed from there if the engine continues to run rich. Gar Williams
 
If it is running too rich with the gas adj valve closed the compensater jet is too large. Try a smaller one generally a jet of .036 inches will work well. You can generally buy a set of number drills at a hobby shop to measure the jets. The other problem if the air maze is plugged you will be choking the carb and of course this will make it run rich. Bill Edstrom
 
If it is running too rich with the gas adj valve closed the compensater jet is too large. Try a smaller one generally a jet of .036 inches will work well. You can generally buy a set of number drills at a hobby shop to measure the jets. The other problem if the air maze is plugged you will be choking the carb and of course this will make it run rich. Bill Edstrom

Hi Bill,

Where is a good place to buy other Jets that fit?
 
You must check all jets even the new ones you buy to ensure they are the correct size. There are several carb rebuild books that are sold by suppliers or by MARC and MAFCA that will provide you with detailed instructions and they are not difficult to follow. The jets can be resized if too large by soldering them shut and redrilling them to size or if they are too small just enlarging them with a larger drill. Some people check the size with a drill of a known size others flow test as was done by Ford. Details are provided in the rebuild manuals.
 
Tube, the carb books that are pretty good are Zenth Carb by Steve Pargeter and A&B Carb Rebuilding by Gorden Bigger. I would also recommend that you go to Vince Falter's web site at www.deucegarage.com and you find jet sizing info the he has put together. Snyder's has the books.
 
Hi Bill,

Thanks for the book names, I appreciate it and will pick one or two up.

The idea of filling with solder and re-drilling is interesting. I removed the old float and installed a new float last night. Reason being the old float had the typically worn spot from the needle showing a little and the new float had much more solder on it to keep the hinge from moving. I think it improved things some but still seems rich even without the air filter.

I have no problem experimenting with jet sizes, in fact I look forward to it :)
 
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