carb questions

[scroller bill]

Hi all. vehicle info in my signature.

I'm not sure what carb I have here but it came off an 86 f series so it should be good for my 85.

Shown are 4 pictures of the carb with various items identified with a letter. Some of the items I have identified through a repair manual but some the manual does not show or say what it is. So here it goes.

First pic: What is this small port on the bottom left of the exhaust manifold? It looks like a small tube was

broke off of it.

Second pic: A- is this the throttle position sensor?

B- is this the feedback solenoid?

C- is this the choke pulldown diaphram and does that hose go to it?

Third pic: D- is this the dashpot? if so, it only has electric going to it. in my vacuum hose routing diagram

it shows a red vacuum hose going to it. Is this going to be a problem?

Forth pic: E- what is this internal thread fitting?

F- what is this port?

G- what is this port?

I know i'm dumping alot into one post but any info would be greatly appreciated.

I have a couple of other questions but they can wait till the weekend.

Thanks, Bill

 

[Seabronc]

Hi all. vehicle info in my signature.

I'm not sure what carb I have here but it came off an 86 f series so it should be good for my 85.

Shown are 4 pictures of the carb with various items identified with a letter. Some of the items I have identified through a repair manual but some the manual does not show or say what it is. So here it goes.

First pic: What is this small port on the bottom left of the exhaust manifold? It looks like a small tube was

broke off of it.See my comment about heat pipe, (Shop manual says used on non electric choke version only) It appears that it was originally a non electric choke version that was converted.

That is a Carter YFA-1V Carborator with Idle Speed Control Motor and Feedback Control.

Second pic: A- is this the throttle position sensor? Yes

B- is this the feedback solenoid? Yes

C- is this the choke pulldown diaphram and does that hose go to it? Yes and Yes

Third pic: D- is this the dashpot? if so, it only has electric going to it. in my vacuum hose routing diagram

it shows a red vacuum hose going to it. Is this going to be a problem?

Sort of, it serves the same function. The book refers to this particular style as an Idle Speed Control D.C. Motor. Controlled by the EEC. Do you have a plug connection for it? If your diagram has a vacuum line (red = main vacuum) then your truck originally had a non-feedback carb and the one you have there is a feed back version, you may need the EEC and harness from the truck you got it from. The feedback carb is mainly for trucks that operate at high altitudes

Forth pic: E- what is this internal thread fitting? Some engines used a heat pipe to from the exhaust manafold to warm the choke spring. Check this before actually connecting it to that broken fitting on the exhaust manafold

F- what is this port? Choke fresh air (Shop Manual says used on non electric choke only)

G- what is this port? Spark port

The one you didn't ask about next to the fuel filter is the Bowl Vent

I know i'm dumping alot into one post but any info would be greatly appreciated.

I have a couple of other questions but they can wait till the weekend.

Thanks, Bill

If your emissions diagram ha

Good luck

 

[scroller bill]

Thanks seabronc. Your response was much appreciated. I have a couple more questions relating to your response.

1. With the carb I have, can i plug the threaded fitting and cap the choke fresh air port?

2. Can i replace the electric idle speed control with a vacuum controled dashpot?

3. Can I remove the feedback solenoid and put a gasket and cover plate where it mounts?

After all the above mods, will the carb finction properly?

4. The bowl vent goes to the charcoal canister, correct?

The choke has one wire going to it so I assume that it is electric. Does the choke get its ground through the carb?

One last question. The spark port, where does it go? or can it be capped like the one on my Holley 4 barrel?

I probably should have told you that the intake and exhaust manifold came from one junkyard and the carb from another junkyard.

I sure hope you don't mind answering all my questions, I know I have alot of them. I just don' want to be a PITA.

I'm not a mechanic per say but very mechanicly inclined. I am very resourcfull when it comes to making something work wether it be modifying or fabricating to make it work. I spent many a sleepless night because I had an idea and trying think of ways to make it work. Also I'm getting pretty good at scrounging for the things I need.

Any way, I've babled on too long.

When this project is done, thanks to you, you will definately see some before and after pictures.

Thanks ooh wise one >

Bill

 

[Seabronc]

Thanks seabronc. Your response was much appreciated. I have a couple more questions relating to your response.

1. With the carb I have, can i plug the threaded fitting and cap the choke fresh air port? After looking at some other information I have, I need to retract that statement about your carb being converted to electric choke. It is an electric choke with hot air assist. It needs the connection for the choke to work properly. the electric connection is to the 7.2V alternator Stator tap.

2. Can i replace the electric idle speed control with a vacuum controled dashpot? Probably if you can get the parts.

3. Can I remove the feedback solenoid and put a gasket and cover plate where it mounts?

After all the above mods, will the carb finction properly?I think I'd go out and buy a new carb rather than try converting this one. Try this place http://www.guaranteedcarbs.com/fasttracklookup.htm

4. The bowl vent goes to the charcoal canister, correct? Yes

The choke has one wire going to it so I assume that it is electric. Does the choke get its ground through the carb? Yes, it depends on the bolts and carb body to get it's ground

One last question. The spark port, where does it go? If you don't have a vacuum advance on the distributor, then cap it

or can it be capped like the one on my Holley 4 barrel?

I probably should have told you that the intake and exhaust manifold came from one junkyard and the carb from another junkyard.

I sure hope you don't mind answering all my questions, I know I have alot of them. I just don' want to be a PITA.

I'm not a mechanic per say but very mechanicly inclined. I am very resourcfull when it comes to making something work wether it be modifying or fabricating to make it work. I spent many a sleepless night because I had an idea and trying think of ways to make it work. Also I'm getting pretty good at scrounging for the things I need.

Any way, I've babled on too long.

When this project is done, thanks to you, you will definately see some before and after pictures.

Thanks ooh wise one >

Bill