as the title says i am having a bit of a problem. i have torn this carb apart i dont know how many time but here goes

when i start the motor it will run fine and smooth then it will get real choppy and idle rough almost as if it is running out of fuel then it wil idle fine again and it will do this asllong as i am runing the motor. what are your thoughts.

the carb is a holley 1920

_________________
1969 Dodge Dart 4 Door 225 SL6

If the float is too high it will cause this problem. Recheck for proper height.

I went to the race track a few weeks ago and my car started this nonsense and I couldn't find a thing wrong until I pulled the bowl and allot more gas came out than I am use to seeing. I have a cut down Folgers plastic coffee can that I use to catch the gas. It was almost spilled over. I re-adjusted the float and problem solved.

If the car is truly running fine except for this problem, then give it a try and let us know. It only takes about 3 minutes to do.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

i will try it later on and let you know in the morning

_________________
1969 Dodge Dart 4 Door 225 SL6

Is this a new float or the old float in the carb?

If new, readjust.. of old... time to order a new one, and pitch it before it sinks on you...

-D.Idiot

ok this is a new float.

i do not see an adjustment for it. the float sits on a spring and bobs up and down, the spring is not too stiff i checked for that when i opened it up the first time.

i do efi stuff so 1 bbl carbs are new to me. i can rebuild and calibrate 4bbl's without any problems but i just cant seem to figure this one out. your help is much appreciated.

like i said before it does this non stop runs real smooth then rough over and over and over back and forth.

_________________
1969 Dodge Dart 4 Door 225 SL6

Did you set the float level per the Factory Service Manual?
or just install it without adjustment?

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

i do not have an FSM would you please enlighten me, as i said this type of carb is new to me.

_________________
1969 Dodge Dart 4 Door 225 SL6

Hi shaun, I will try and lend my experience I had with my 1920 and hopefully help some.
I did not have the problem you have but carbs are carbs and all can suffer from some kind of malady. Anyway, and this is from memory of months ago, there is a brass inlet fitting that screws into the carb body that holds the inlet check needle that the float arm rides against. the float will push this needle outward to shut off the flow of fuel when the float bowl is full and set correctly. The factory lists a special tool to set the level (C-3903) which I did/do not have. I inverted the carb with the float on the pivot pin and adjusted the float by bending the adjusting tab until the float sat level. The adjusting tab is the one that touches the inlet needle mentioned above.
My car starts, idles, and runs fine.
Make sure your fuel pressure is not to high or too low, 5-6 psi I think is ok.
Hope this helps
Dee

_________________
1971 GTX 440, 727, 3.91, stock except cam
1972 Slant 6 mor-dor Dart stock except minor rust
1984 Dodge Rampage 2.2 OEM stock
1986 Plymouth Duster 2.2 OEM stock
2007 5.7 TRD Tundra, fast for a truck
stopping is cheap, going is expensive

Holley 1920s suck. I am getting worse performance from mine than with my 1945. The 1920 does have better idle quality and drivability, but the performance is dull. Thats why I am converting to a super six, and selling my 1920, if anyone will buy. I have good money into this carb, and don't want to see it go to waste.

_________________

'74 Duster 225 Super Six w/904
14" Cragar SS wheels

dusterguy225,

Mine used to be like that but after modifying it extensively it has really come to life for a 1920. In fact with a #62 jet it feels like a 318 2 barrel under the hood. There is a thread on some of the mods I have done with pictures that SL6 Dan posted for me.

Any carb can be lack luster including the 1945. The 1920 is just much quicker and simpler to work on. Jet changes take less than 3 minutes. Install the dual plunger economizer body and set up the pump shot it will surprise you. I love passing folks or stomping on it at a light. It can be allot of fun! One of the main things I found on mine was that the idle air bleed was plugged, with lead potting compound and I had to drill it out. That helped the transition from low to high.

For my engine build these are my current settings.

Specifications on the R7585 1920 Holley Economaster

On jet sizes, I am always referring to the main jet. A #61-2 which is a .060 diam. hole factory tuned half way between a #61 and #62.
Idle air bleed: .035 which is the same as a #65 drill bit.
The idle mixture hole: .09375, 3/32 in diameter.
The accelerator pump hole: .035 in diameter.
Idle mixture screw: 3.5 turns out set at 750 rpm out of gear at 18" vacuum.
600 rpm in gear @ 16" vacuum

I run a fuel regulator set at 5 lbs.

Hope this helps.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Wrong. Carbs in bad condition, improper repair, and/or improper adjustment suck. It's specious to generalise from difficulties you think you understand, to grand assertions like "Holley 1920s suck".

To the original poster: Yes, absolutely the float level is adjustable and must be correctly adjusted by bending the tang on the float arm which bears against the fuel inlet needle valve so as to attain the correct float height as stipulated in the service manual and/or carburetor kit instruction sheet.

Also, the factory service manual is a mandatory tool to be bought first, not an optional one to be bought eventually maybe sometime later.

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.

A 612 jet is a close limit jet 2 being middle of the road and a 'perfect' #61 jet... a 611 would flow a bit on the lean side, and a 613 would be on the rich side... these are 'specific' for calibration in emissions style carbs where calibrations to pass smog is critical...

-D.Idiot

Good explanation DI. Thanks.....just along day today......

I have lots of Holley jets however, the 61-2 I pulled from one of my 1945's.
Try it if you want some good performance out of the 1920 and still maintain good mileage. When I was running it earlier this year, I was getting 22.5 mpg with it. The #64 netted 22 mpg, but felt a sluggish not as crisp with the stock high speed air bleed.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

I helped my grandfather rebuild this carb, and he has rebuilt many over the years. It has a new float (adjusted right) and all new internals that I ordered from the Daytona Parts Co.

I say they suck, because I went from the 1945 getting "ok" gas milage, to the 1920 getting about 13-15 mpg. I have heard that is pretty common for them. Also it hesitates a little when you accelerate too hard.

I switched carbs because I had read that 1920s give better fuel economy, as well as better performance, aside from the fact that my 1945 took forever to warm up and the choke was broke. The only thing I got out of the 1920 was a smoother running car with reduced performance.

_________________

'74 Duster 225 Super Six w/904
14" Cragar SS wheels

dusterguy225,

Use the search funtion and read the thread on tuning the 1920 and down load the pdf manual SL6 Dan posted. Your missing out on allot. I have rebuilt many 1920's so has Dan, Doc, DI, Rock, Ceej and many others on this site and they can provide excellent mileage. Yours sounds like you have over looked some key items like a leaky choke pull off or the shaft needs to be rebushed, or an incomplete economizer body, poorly shimmed power valve, etc.

I rebuilt one once that was covered in white powder from oxidation sitting in a box full of pine needles and leaves that was outside for years under a tree. When rebuilt the worst it got was 18 mpg and most of the time 20 to 21 mpg. on a stock engine. I will say it again, it will break loose the 2.76 ratio 8 3/4 posi rear-end at will with the 1920. Granted it's no four barrel, but it is very respectable if tuned per the FSM or modified like I have outlined.

I would suggest that you carefully go over it again and fix the problems and then rejet it for performance.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG