84 Ranger Carb Identification

[Ralleytuned]

Need some help, got a new to me 84 ranger, I was told it was the 2.3. Trying to find out what carb this is so I can start figuring this thing out. Runs pretty good overall, read a lot of threads here already and have just started to tinker on the ol rig. It def runs a little rich at startup, and has a sligth hesitation on light throttle in some spots. Would like to get it running a little cleaner, its only getting 16mpg average on the last tank

Here is a shot of the carb, its had a exhaust manifold replaced and a bunch of the emissions stuff removed

 

[tomw]

Things to check off the top of my head.
1)float level. what is the level of fuel in the float bowl?
2)idle mix adjustment. with engine normal temp, engine at idle, screw in until the engine starts to miss, screw out until you get a slight misfire due to rich, screw back in half the turns towards the lean(screwed in) misfire position. For mpg, tend towards lean, but not misfire. I'd turn in to poor idle, then back out until it got smooth, then stop.
3)choke - has a vacuum 'pulldown' that will pull the choke plate open ~1/8"-1/4" once the engine starts. Is a diaphragm with a connecting rod that will yank on the choke linkage to allow more air once the engine fires. Adjust to have a fully-seated diaphragm & link open the choke plate. Sometimes a drill size is specified for how much 'open' the choke plate is to be set at.
4)accelerator pump - is a squirter that juices fuel flow when you step on the gas pedal. The air flowing through the carburetor will zoooom fast when you open the throttle, BUT the fuel, being more dense, will take a bit longer to accelerate and catch up to the air flow speed. The accelerator pump squirts a bit of fuel directly into the venturi or airflow in the carb to enrich the mix until the liquid fuel can get up to speed. They are adjusted so that the engine doesn't stumble when you open the throttle quickly on a hot(normal) engine.
5)idle stop. - the throttle plates should not be allowed to close 100% unless you have a 'kicker' solenoid that is turned on by the ignition switch. Some say you can scratch the insides. I've never seen it. Anyway, you can set the idle speed by adjusting how 'open' the throttle plate is when the linkage is at rest. Most should be in the 750-800 rpm range, but for emissions, it may be 900rpm. Again, with the engine at normal operating temperature(why you need to have a GOOD thermostat installed - consistent temp), you can screw the idle stop screw in and out to position the throttle plate so you get the idle speed you want. Generally, once you get the rpm you like, you'll bip the throttle open, (checking accelerator pump for hesitation/stall) and let it 'snap' closed. The engine should rev, and then slow down, without stumble or stall.
I would also check that the carburetor is tight on the intake. Some engines (200 six) were known to have carburetors that worked their way loose, and allowed excess air into the intake causing misfire.
X) the choke is electric assist, and most are set with no adjustment. If it is adjustable, you want a cold engine choke to snap closed, gently, when you step on the gas pedal. At the same time, when the choke closes, it should move a cam (stepped) into position on the linkage to hold the throttle plate more open than the normal, hot idle setting. As the engine warms, the choke spring will relax, and allow the choke plate to close. It will NOT move the throttle linkage and allow the throttle plate to get to normal unless you step on the gas and release the gravity-moved stepped cam. If you were driving, as you changed throttle position, the steps would get smaller and smaller, and can move with the throttle open in normal driving. Thus the engine idle will slow as the engine warms.
I probably forgot something, but this is enough to get started.
tom

add: You likely have a 2.0, but you can check the VIN for the engine letter code to be sure. I know the CA 2.3 engines were EFI, but am not sure on the 49-state versions, whether they were EFI or both the 2.0 & 2.3 were carb'd.

 

[Ralleytuned]

Thanks for the detailed reply, all things i intend to check, once i know what carb I am working with.

From what I can see, there is no idle mixture screw, only idle speed adjustment screws. The choke works well, and the high idle works after I pump the gas 3 times before starting. It fires right up, idles high for as long as i feel and when i hit the gas once more it returns to a somewhat normal idle speed, which increases slowly as it warms up.

It drives fine, but i can tell there is some adjustment needed. Plus in the photo you will notice some leaky gaskets, I intend to rebuild the carb and check all the adjustments, but again, I dont know what engine or carb im working with haha

 

[Mark_88]

I started to search for the carb that was used on these vehicles in the one bbl config...there are many pictures on the internet that are close but most of those have air fuel mix screws at the base...

What you are saying is that it is not fuel efficient and has some dead spots in throttle response.

Two things come to mind...one is the cable may be stretched and needs tightening up. If you have slack in the cable there is not a consistent pull on the accelerator and it could simply feel like there is no response...check that out...there is a quick fix with zip ties if there is slack...buying a new cable is also an option as I found one recently available in Canadian Tire...main issue is it costs $80 CD...less if you are in the states.

The other issue is it is probably due for a rebuild unless you've had that done recently yourself...they get passages clogged up and whatnot...leaky power valves on some models...and if you don't have air/fuel screws they pretty much can stop functioning if something is plugged up.

Here is a list of carburetors used in the four cylinder engines...with rebuild kits listed. You will need to find that little ID plate that is usually attached to the carb body somewhere...that is critical for ordering parts.

http://carbkitsource.com/carbs/catalog/Ford/Ford4.htm

Looks like the C-1 YFA was used for your year...and probably many other vehicles...if you search on "C1 YFA" you should find a match for what you have...image wise...

Hardest part of identifying them from a picture is if you only get partial images it can look like many other parts...but knowing that year and make can narrow it down very fast...

 

[RayInStl]

Yup. That's the lovely computer controlled YF-A. What a lovely turd of a carburetor. I hope you have better luck than I did. I'm planning to replace mine with a non-computer controlled Motorcraft 2100 2bbl.

If it's of interest, you can remove the duraspark computer controls and wire a GM 4 pin HEI module up to the stock distributor. I did that on mine because most of the emissions equipment was either missing, disconnected, or had been damaged by what I assume was a carburetor fire.

Good luck with the new truck. You should post some pics of the rest of her. First gens rock.

 

[Ralleytuned]

Yes its definitley the computer controlled one. I honestly have no issues replacing the carb if I cannot get this to get some better economy. The last tank was only about 16mpg, but I was pushing her pretty hard with some heavy loads going over the mtn pass haha

This was a free truck and I mostly use it for dump runs and hauling my dirt bikes around, I love it so far but it needs some love. As the weather changes, so does the running of the truck (big surprise right haha). the stumble has cleared up on its own since I have been using 89 oct, the stumble came after putting in some better oct gas haha.

I think I am going to toss in a Mallory 6A ignition box to pump up the spark power, I have used them in other carbed vehicles and they seem to really like having some more power firing the plugs.

Thank you all for the info! Back to the searching...

 

[Mark_88]

Did you check for play in the cable? That is a very common cause of poor throttle response and a super easy fix...without changing anything or costing a small fortune...