Hey guys new to the forums. Out of options for my 85 f150 truck besides paying mechanic. Friend and I rebuilt my carburetor and now its acting up because of something we might have done wrong. Heres whats going on:

1. Truck requires gas pedal mashed in to start, and still starts very hard.

2. Truck requires pedal to continuously be pushed about 1/4 in to keep it running till it warms up.

3. Adjustment screw and idle screw have little to no effect on the engine running.

4. Rough idle before warmed, High idle when warmed up

5. A loud sucking/ vacuum noise that sounds like a jet engine, its doing that as well consistently.

6. Carb is smoking on the inside after only about 2 minutes running, and smoking quite a bit when warmed up.

7. A bit rough when turned off.



Things I've tried:

Messing with spark plug wires

Finding a vacuum leak

Maybe the gasket between the manifold and carb is off?

Adjustment screws

The rebuild kit that was used wasn't entirely made for this carb but was very very similar. A few gaskets that had extra screw holes were snipped off. (I'm no mechanic and learned everything I know now about mechanics from this truck, still learning) The gaskets still fit snug as far as I could tell.
The float wasn't replaced because it didn't come with a rebuild kit. The carb was bathed in gasoline to clean, also when we took the carb apart we found a fairly large rubber piece stuck inside the carb beneath the butterfly (choke, throttle cable) people keep naming off different things to me about what that is. If you guys have any info about what could be wrong please say so. My trucks my daily driver and my baby lol I don't wana lose her.

 

What engine and carb do you have?

 

Inline 6 4.9l 1 barrel carb as for the model I really have no idea. Theres supposed to be a tag on the carb that identifies it but thats not there. Anyway I'm able to find out?

 

I was going to guess it was a 4.9. If you have the stock carb, it is a Carter YFA 1 bbl.
I have rebuilt many carbs over the past 30+ years, and I have never had a carb that was such a PITA to rebuild. It all looks fairly simple and easy, but it never runs right on the first try. I always end up pulling it apart at least one more time to change some adjustment.

It sounds to me like, among other things, you may have a major vacuum leak, either in the carburetor itself, or somewhere in the intake system. You may have a gasket that has a hole somewhere where it shouldn't (you said it was not the right kit). Also, make sure the top and bottom half of the carb body are screwed tightly together. These screws come up from the bottom and can only be accessed with the carb removed from the manifold. If you don't have the right kit, and you don't have the metal tag from the carb, you are probably just guessing about the float height setting - there is a table in the rebuild kit where you look up the number from your metal tag to find the correct float height setting.

 

Ok, common problem with these carbs is the accelerator pump/power enrichment diaphram. If it gets kinked or torn the engine will run dead rich. What brand of carb kit did you use? I have run into a few over the years that are nothing but trouble. On the side of the main body, just above the gasket there is sometimes a stamped number. It will be 4 or 5 digits probably followed by S or SA. This is the Carter ID number, there may also be a Ford number stamped in somewhere, it will in the form E5TF-ABA as an example. The 9510 in the middle is understood. When you assemble the throttle body to the float bowl, I always use Loctite on the screws so they won't back out. Since you probably discarded the old gaskets, you are going to have to make sure you didn't cover any passages on the idle circuit. One more area of problem on these is the spacer under the carburetor. It has a gasket between it and the manifold and it can leak also. Try disconnecting the EGR valve vacuum to make sure it isn't opening. If the EGR pipe gets hot even with no vacuum, then the EGR valve may be stuck or bad. Good luck with it.

 

I used Gp sorensen thanks for the advice guys. Ill tear it down sometime this week see If I can't locate the problem. Was this kit that I used a bad idea?

 

I have used two of the GP Sorensen kits. When I bought the first kit (about 3 years ago) the parts guy had a hard time finding it. His computer said he had one, but it took 15 minutes to find it. The box was covered in dust, you couldn't even tell what color the box was until he wiped it off with a rag. It was the only one withing 100 miles, so I bought it. The accelerator pump diaphragm lasted about two months, then deteriorated. I bought a new GP Sorensen kit from an online store and rebuild it again. I have been running it for the past almost 3 years without any problems. That first kit had probably been sitting in that parts store for 20 years. The second one was in a pristine box, looked new.

 

Here is the right GP Sorenson carb kit for the YFA carb
and here is where the carb number is located under teh front of the bowl

 

GP Sorensen is a good brand, I use them myself.

 

We are going to tear it down again here in a few minutes going to use some of the tips ya'll gave me. Will keep you updated thanks again.