Replacement vs Rebuild
Holley vs Carter
2bbl vs 1bbl

Any fans of the Carter YFA? I like the idea of rebuilding the old carb, a friend at work says I should just throw it away and get a Holly 2bbl.

I am not trying to hot rod my truck but I would like to feel some power on the accelorator. If I pony up an go with 2bbl Holley, which on should I get. What are the things to watch for during replacement?

I am currently expiriancing desieling, high idling in neutral, lack of power, and recently hard starts. I know two vacuum tubes are rusted off of the manifold. One is the choke heater tube and another goes from the base of the carb to the manifold. So there is some leakage.

I am told that there are many tubes on these carbs for emmisions standards. Will the Holley have these many tube holes? Luckily I don't have emmisions to worry about since it is classified as "Historic" in Maryland.

Any suggestions will be greatly appriciated.

Thanks

DC

 

Oh this if for a 85 300 I6

Thanks again

 

If youve ever rebuilt a carb the YFA is a cakewalk. very simple and easy to rebuild. If you pull it off and bring it in any good parts store sould get you a rebuild kit. A 2bbl or 4bbl will require an aftermarket manifold. I want one for my 300 but the 350 dollar price makes me wait. as for getting rid of emissions and such my 85 has none no carb preheat and a manual choke. Ill start it in a 30 bellow ND morning without a blockheater. The YFA is bone solid reliable and easy to tune.

Id rebuild the carb, tune up the engine, and if you decide to junk the emissions makesure you block off all vacum lines or you wont idell at all. makesure to hook up your vacum advance on your distributor and your brakes.

Great ol carb served for 20 years

 

Welcome to the site.

The problems you are experiencing now are not the fault of the Carter; they will happen with any improperly tuned carb. Dieseling is caused by vacuum leaks, late ignition timing, and high idle, or overly hot combustion chamber temperature. On these engines it is usually the result of a blown EGR valve. Your high idle is caused by either vacuum leaks or improperly adjusted curb idle.

You will find more power with the Holley (look at the Holley 2300) but it is not a cakewalk. I've heard of 1 bbl to 2 bbl adapters, but I haven't seen one and I've heard they're very very pricey. Your other option would be to upgrade to a 4 barrel intake and use a 4-to-2 barrel adapter, but be aware that you will be looking at redoing your entire throttle and kickdown linkage, and the new choke will have to be fully electric. Plus you'd have to swap the manifold, and on these engines it means unbolting the exhaust and intake together which can be a nightmare if any of your studs are rusted. It is a huge project, and a 4-barrel intake is pricey ($200-300).

Usually carbs offer ported vacuum; some offer taps for manifold vacuum as well. Whether or not your Holley would have them depends on what manifold upgrade you do. If you find an adapter for your 1 barrel intake, then you can probably tap vacuum off what you presently have. If you upgrade to a 4 barrel intake, it depends on the intake - for example the Offy intakes have holes drilled for vacuum trees.

Rebuilding the Carter you have now will be the cheapest, easiest and quickest route. Figure $20 for a good kit, $20 for the gallon can of chem-dip, and an extra $10 for base\spacer gaskets, fuel filter and spray cans. $50 and you're out of the garage, plus whatever it takes you to fix your rusted metal vacuum lines. If you don't have a whole lot of experience with engines, I would go this route because it's a matter of replacing\repairing your current stock setup rather than adding anything new. The YFA is a great carb; I used to run one on my '79 and it had plenty of power with the stock setup. Currently in the process of the 4-barrel upgrade. After I had everything torn down and thoroughly cleaned, it took me 20 minutes tops to put that carb back together. Not much that can go wrong with these things. You want to make sure you get those vacuum lines fixed though. The first one you mentioned is for your choke; I can't follow what you mean by the second one but if I had to guess I'd say that's for your PCV.

 

"You want to make sure you get those vacuum lines fixed though."

That is the first thing to do. Carbs unfortunately get 95%+ of the blame when there are other systems on the engine that are not in proper working order.

 

Thanks for the advice from the both. Sounds like I am rebuilding a carb soon.

fmc400,

The second hose goes is actually a rubber hose mixed in with metal. If you are looking at the carb it comes out of the bottom left and goes to the back of the manifold.

PCV? Is there somewhere I can go for a good hose diagram? Another thing...Would you use JB Weld? To re-attach the hoses to the manifold?

Thanks

 

There wouldn't be a hose that goes from the carb to the manifold. The carb is already connected to the manifold, it sources its vacuum directly. The hose you are probably thinking about is the transmission modulator line. It starts out as a rubber hose tapping off manifold vacuum, runs past the back of the intake manifold, and then connects to a metal line that runs down to the transmission. Unless you are talking about the vacuum tree that threads into the manifold and has several taps for smaller vacuum hoses. That is metal.

PCV stands for positive crankcase ventilation. You have a hose from manifold vacuum to a PCV valve which sits in the valve cover. You also have another hose running from the filler cap back to the air cleaner. PCV is a way to cycle fresh air through the engine's crankcase and re-burn fumes that shoot past the piston rings during combustion.

Autozone's website has vacuum diagrams that you can look up based on vehicle year, make and engine.

As for the JB weld - which hoses are you talking about exactly? The only hoses that connect to the manifold start off of the vacuum tree that threads into the manifold. If your vacuum tree is rusted out you should replace it. If you are talking about the choke stove tube, you shouldn't use JB weld on it. Things like lines and tubes shouldn't be fixed with JB weld; they're so cheap that they should just be replaced. JB weld is something you use as a last-ditch effort to save something that would be expensive to replace, like an intake.

Honestly though, take care of the vacuum lines before you rebuild the carb. You know for sure that they're bad, you don't have enough justification to blame the carb until you have the for-sure things fixed. Maybe the carb is fine, it just looks like a carb problem masked by the rusted vacuum lines, as Harte3 alluded to. If your truck starts fine, doesn't bog down and stumble when you get on the gas, and gets you decent mileage, the carb probably doesn't need a rebuild. My money is on vacuum leaks and a blown EGR valve.

 

I had the exact same problem with my carter on my 300, i rebuilt it and tuned up the engine (timing, choke, etc) and now it starts in any tempurature, it also has a hell of alot more power since the rebuild and tuning. currently im looking to upgrade to the 4bbl. myself but the carter is an awesome carb definatly rebuild it and check your ignition timing!

 

PCV hose running from the filler cap back to the air cleaner This is missing from the PCV...
And I traced the PCV from the Carb to the valve cover. There was an oily build up around the base of where the PCV hose enters the manifold. Any thoughs?
What about the Vapor Canaster? One side of Canister there is a hose, of course, the other there is nothing? Something is wrong there.

Thanks for all of your help. I will get around to those others hoses coming off of the carb. later.

 

Needs to be replaced. Sometimes people remove these on vehicles when the blow-by is so bad that it keeps fouling the air filter. If this is not the case for you, you need to obtain a new hose.

Normal for an old engine.

The purpose of the cannister is to collect fuel vapors and feed them back to the engine to be re-burned. Often there will be a line from the fuel tank running up to the cannister, and a hose from the carb (bowl vent) as well. A return hose runs back to the choke tower of the carb. Lastly, a vacuum line runs to the purge valve on top of the cannister. This is ported vacuum and it is often teed off the EGR valve line. When you step on the gas, the valve "purges" the fumes back up to the carburetor.

 

I think that vapor canister needs to be replace too.

Another can of worms that I could use a suggestion on. Oil building up around the outside of the oil pan. It isn't steady but it is noticable. The truck sat for a long time so I am thinking the gaskets need to be replaced. It almost looks like a condensation.
And when I get the engine preasure correct in the engine what with that do to the gaskets. Or should I change those out too.

Thanks

 

It's normal for an old engine to have oil build up around the oil pan. The rear main seal leaks after a while. How much oil are we talking about? Be aware that changing out an oil pan almost always means lifiting the engine and is a considerable amount of labor, so you only want to do it if you absolutely have to.

I'm sorry, I do not understand this question.