I originally posted this in the wrong section.....



My 390 has a 2 bbl intake. I wanted to throw a 4 on, but I don't feel like messing with it anymore, haha, at least for now or anytime soon. It's our extra vehical, I only drive it twice a week, roughly 75 or 100 miles max a week. I just wanna get the truck is good operating order, I'll play with a 4 bbl down the road.

Ok, currently I'm running a Motorcraft carb (manual choke capable, but I don't have a choke line yet, the truck originally had a 4 bbl Holley factory automatic choke but i swapped engines, old one died). I have some hesitation and the carb hasn't been rebuilt in quite a long time (from what the previous owner of the engine told me) My grandfather looked at it and said "oohhh all that needs is a good old fashioned rebuild!" He knows his stuff, if he has an engine, he can fix it! He said it probably just needs an accelorator pump, but might as well rebuild it since I'll have it off.

Someone gave me a Holley 2 bbl carb (with 4412 1 1221 on it), has a manual choke. It def needs rebuilt, it's dirty and I wouldn't trust it. This carb is aftermarket, correct?

I also got a free Autolite 2 bbl. (i'm the king of free stuff, I tell ya!) It has C9AF C C 9E 16 printed on it. It has electric choke. The man who gave it to me also gave me a rebuild kit with it. Any details on this carb? What'd it come off of? Anything would be helpful. It appears to be in good shape, it's clean and I have a kit to rebuild it!

Which of the 3 carbs would you rebuild and run? I would prefer to do either the Holley or the Autolite so I can at least drive my truck while I rebuild a carb and take my time, I've never rebuilt one, so I don't know how long it'll take me or what I'm doing. But I'm sure I can figure it out. Plus my grandfather said he'd help me if I needed, but I wanna try it myself. Or do you think I ought to redo the Motorcraft? My grandfather said Holley carbs are the best (his opinion) and I should slap that one on, but my dad said the Autolite I have is "the best carb ever built" (again, his opinion!)

Now it's your turn, gimme your opinions please!

Also- is it possible to make the electric choke work from the Autolite? My truck now doesn't have ANY choke and it sucks!

help me help me help me!

 

Personally, I would throw a kit in the 0-4412 and use it. Good carbs!!

 

I agree,do the 4412, its a large 2 barrell anyway and you should be able to hook a choke up fairly easily on it also.. manual or electric whichever you have at hand..

 

kadrocker,
I know it's been a few days since you posted your question - but maybe you're still thinking about you choices.

On your Autolite carb, there is a number that is located on the side of the float bowl, right behind the accelerator pump rod, inside of a circle; like 1.23 or 1.33.
What is that number on the Autolite carb?

That number coincides with a given cfm flow rating. Since you're running a 390, it would probably be happiest with at least a 1.23 (356 cfm) or a 1.33 (424 cfm) Autolite carb. If it's a smaller number, like 1.12 (300 cfm) it likely would be too small for your 390 to be happy.

I believe the Holley #4412 is rated at 500 cfms, so it would flow more air/fuel mixture into your 390 than the Autolite carb. 500 cfm, is likely as large of flow as you'll find from most common 2bbl carbs.

Your ideal carb size should be determined after considering what rpm range your operate your 390. If your truck is mainly a street driven, it likely sees a rpm range of 1,000 to 4,000 rpms, which means it isn't 'breathing as hard' as if it was running at 5,000 rpms. So, at 4,000 rpms, it only would need a 450-500 cfm carb whereas if you ran it at 5,000 rpms, it would be much happier with a 600 or larger cfm carb (which would likely mean you'd want to step up to a 4barrel carb to get that much flow).

ANYWAY, to summarize:
-- your Motorcraft carb is giving you problems.

-- you have a nice Autolite in hand and a rebuild kit to go into it, but you don't know if it'll feed your 390 and keep it happy.

-- you have a Holley that would likely be capable to feed your 390 and keep it happy, but it needs at least a good cleaning and probably a kit and maybe more to get it ready to run.

At this point, I'd recommend you take your time and put the kit into the Autolite carb and give it a try. You already have it in hand. However, if you think the Autolite might be too small and not flowing enough air/fuel mixture for your driving rpm range, then clean up the Holley and get a kit and whatever else it needs put into it and then give it a whirl.

Good Luck!
BarnieTrk

 

BarnieTrk- that's a very good post man! Thanks a bunch!


I haven't chosen a carb just yet.

I had a friend check out the Holley- he said there are some pieces missing to it, boo! He said i'd have to put a few bucks into the carb plus buy a rebuild kit- ehh, didn't wanna spend the $$$ right now. So I'll hold off for now, maybe I'll sell the Holley, we'll see. As he put it- "this carb is in rough shape, it's seen some use and looks tired"

The Autolite- he looked at that one and said he looks complete and nice and clean, but he looked at the rebuild kit (which was opened) and said there's a few pieces missing! Doh! He also showed me a vacuum port on the carb that is threaded, it's slighlty bent, he said it might give me trouble, grr! I just can't win! He did say I wouldn't know unless I tried. On yeah- it has 1.23 printed on it.

I might just stick with my Motorcraft for now, I need a new accelerator pump, which i can put in without removing the carb.

I haven't made a decision yet on what I wanna do. Still up in the air!

Thanks for the reply though! I really do appreciate it.

 

kadrocker,
No problem...glad to help ya out.

So, do you know what cfm rating your Motorcraft carb is?
It may have a similar number cast into it just like the Autolite carb. It may also have a metal tag on the front with some model/code #s on it. Either info would be good info to know when you go to get the accelerator pump for it. Depending on the carb, sometimes you can get an accelerator pump with a deluxe rebuild kit. It might be not much more $$ to just take it off and give it a completely fresh rebuild kit, check/set the float and have a fresh carb to go!

BarnieTrk

 

There is a metal tag on the carb. When I get home frm work tonight I'll post it- maybe you can help me decode it.

 

Been a while since I checked this thread....heres what the tag says...

top line: D4PE UA
bottom: A 3L 14

I put a new accelerator pump in, it fixed my high rpm hesitation, but the lower end rpm is still drivng me nuts! This whole hesitation mumbo jumbo has me frustrated!

I'm sure I can do the carb rebuild myself, I'm just afraid of fine tuning the unit. I need to be able to drive my truck every Friday, my wife and I drive together during the week, but on Friday I work different hours and drive the truck.


I believe I'm gonna sell those two other carbs, hopefully someone can use the parts or the carbs, shoot- I hope they're usable at all!

 

kadrocker,
I assume you mean to say that your plan is to sell the Holley and the Autolite, and you'll continue to run the Motorcraft, correct?

My info indicates Ford installed the Motorcraft D4PE-UA 2BBL (2100 series) carb on their '73-'74 trucks with a 390" V-8. So it looks like it should work for your application fine.

Here are my suggestions/recommendations:
I suggest you first replace the fuel filter. Get that done and out of the way. Run the engine to confirm all is well.
Then pickup a Motorcraft 2100 carb rebuild kit (part# CK35) and a 96oz. pail of Gunk-brand carb cleaner & basket kit. The carb kit should be about $33 and the cleaner kit will likely be around $35. The cleaner kit should include a screened parts basket to allow you to submerge the parts in the pail. Call around for your best deal locally. The carb rebuild kit should include all gaskets, needle/seat, accelerator pump and instructions, adjustment settings and a detailed diagram. Read over the instructions a couple of times taking note of what tools you'll need to use to do the rebuild and then plan to start the rebuild on the next Monday.... that will give you thru Friday to Get 'R Dun - with no pressure.

Get a good light in position so you can see good and have a couple of rags handy to soak up the spilled fuel that YOU WILL HAVE. Remove the carb, label or write notes to yourself as to where the vacuum hose plug in and such - you think you'll remember, but it will be easier to take the couple of minutes and write it down or label them now, than burn even more time when you're putting it all back together and start second-guessing yourself. Dis-assemble the carb, soak it overnight in the cleaner. While the carb is soaking, clean the intake manifold top of any old carb gasket. Inspect the mounting studs that they are in good shape. Once the carb has been soaked overnight, remove it, shake it good to remove as much cleaner as you can, then blow out all of the passages with compressed air. If you don't have an air compressor to use, buy a couple cans of compressed air from the computer store, they use it all the time on keyboards and such (they don't cost much $$). Finally, carefully re-assemble it with the new parts and gaskets. Be careful not to over-tighten the carb mounting nuts, the aluminum base plate mounting "ears" will crack easier than you think (- don't ask how I know). Re-connect the fuel line, vacuum lines and install the air cleaner.

When you're ready to crank the engine over, try to have a buddy watching or turning the key while you watch for any squirting fuel, flopping hose, etc. You'll likely need to crank the engine a bit to allow the fuel pump some time to fill the carb fuel bowl. Once it's full, pump the accelerator a bit and it should fire up. Once you've got it running, keep it running and allow it to warm the engine. Once the engine is warm, adjust the carb according to the written instructions.

Good Luck!
BarnieTrk

 

I'll try to get ahold of a rebuild kit and Gunk pail asap!

Come January work'll be slow and I'll have the time to do this stuff.

I'm sure I can do it, I mean I swapped a whole engine before, why can't I rebuild a carb, right?

And yes- I meant keep the Motorcraft and sell the Holley and Autolite.

Thanks for the help/advice/suggestions, it's appreciated!

 

http://www.therangerstation.com/tech..._2150_carb.pdf



oh snap! check that link out!