1983 with 351 engine
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dashpot/choke
Set the idle speed with the truck in gear.
There may be a dashpot on the carb (either vacuum and/or electric) which is used to increase idle speed when AC is on and also keeps throttle blades from closing too fast when you close throttle quickly to keep engine from stalling. Do you see anything like that at the base of the carb (front, throttle cable side)?
Example:Duralast/Dashpot (DP134) | AutoZone.com
There may be a dashpot on the carb (either vacuum and/or electric) which is used to increase idle speed when AC is on and also keeps throttle blades from closing too fast when you close throttle quickly to keep engine from stalling. Do you see anything like that at the base of the carb (front, throttle cable side)?
Example:Duralast/Dashpot (DP134) | AutoZone.com
I think this should answer that question. Is the dash pot the brass colored piece on the left?
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From: Orlando area
Regarding your question about the vacuum advance affecting idle - it should not. The vacuum advance comes from ported vacuum so it has no vacuum at idle. There is only vacuum when the throttle open enough (maybe 10% open) to uncover the vacuum "port" in the carburetor venturi.
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From: Orlando area
For some reason its not letting me post any more pictures from the truck. Below is the album with descriptions that I created.
1983 F150 initial vacuum setup. by Twotall | Ford-Trucks
1983 F150 initial vacuum setup. by Twotall | Ford-Trucks
If you have specific vacuum lines you are asking about, take a picture of the line (or nipple it connects to) and maybe we can help you figure out what is going on. I couldn't see any lines missing (except on Air Cleaner). Are there others?
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I couldn't make out much from your photos. I think I got a case of snow blindness looking at a couple. Did you shot these with a cell phone?
If you have specific vacuum lines you are asking about, take a picture of the line (or nipple it connects to) and maybe we can help you figure out what is going on. I couldn't see any lines missing (except on Air Cleaner). Are there others?
If you have specific vacuum lines you are asking about, take a picture of the line (or nipple it connects to) and maybe we can help you figure out what is going on. I couldn't see any lines missing (except on Air Cleaner). Are there others?
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From: Nebraska
Improvement!!
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From: Orlando area
There are a couple of weird things going on here (as far as I can tell from the photos).
First, I wonder if this is the correct carb because it doesn't have the fuel bowl vent. I see you have the carbon canister bowl vent line (but what is it connected to?). Number "1".
This appears to be the carbon canister vent line. What did you connect it to? is it just laying there (unconnected) in the photo, or does it transition to the smaller hose?
The choke has a "hot air passage" (it draws hot air from around exhaust manifold to aid in heating choke element for faster pull-off). The hose you have connected should be going to the exhaust manifold heat riser fitting.
First, I wonder if this is the correct carb because it doesn't have the fuel bowl vent. I see you have the carbon canister bowl vent line (but what is it connected to?). Number "1".
This appears to be the carbon canister vent line. What did you connect it to? is it just laying there (unconnected) in the photo, or does it transition to the smaller hose?
The choke has a "hot air passage" (it draws hot air from around exhaust manifold to aid in heating choke element for faster pull-off). The hose you have connected should be going to the exhaust manifold heat riser fitting.
pedant
Joined: Jan 2008
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From: EXTREME southwest CT
What is the arm gap set to?
If looking down the bore of the carb, can you see streams of fuel when you work the throttle linkage?
Most Fords are set up for manifold vacuum to the advance.
Using ported vacuum may require major tuning of the distributor.
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From: Orlando area
I looked up the ignition system (distributor advance) in my factory service manual, and in the "general description" it only says that the vacuum advance (ignition timing) is increased as vacuum increases and no advance occurs at idle or during acceleration.
There is also a dual diaphragm (advance unit) on some models where the back diaphragm is connected to "manifold" vacuum but it is used to retard the timing under high vacuum conditions.
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heat riser fitting
Would this fitting be on top of the passenger header? I've looked elsewhere but from what I can tell looking at the diagrams after a Google search of that term, the only heat riser fitting I find is attached there. But there was some talk of there being other parts with this name.
I really appreciate all the input!
I really appreciate all the input!
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current photo.
There are a couple of weird things going on here (as far as I can tell from the photos).
First, I wonder if this is the correct carb because it doesn't have the fuel bowl vent. I see you have the carbon canister bowl vent line (but what is it connected to?). Number "1".
This appears to be the carbon canister vent line. What did you connect it to? is it just laying there (unconnected) in the photo, or does it transition to the smaller hose?
The choke has a "hot air passage" (it draws hot air from around exhaust manifold to aid in heating choke element for faster pull-off). The hose you have connected should be going to the exhaust manifold heat riser fitting.
First, I wonder if this is the correct carb because it doesn't have the fuel bowl vent. I see you have the carbon canister bowl vent line (but what is it connected to?). Number "1".
This appears to be the carbon canister vent line. What did you connect it to? is it just laying there (unconnected) in the photo, or does it transition to the smaller hose?
The choke has a "hot air passage" (it draws hot air from around exhaust manifold to aid in heating choke element for faster pull-off). The hose you have connected should be going to the exhaust manifold heat riser fitting.
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From: Nebraska
research
I've made a few changes... but now the reman starter I bought is throwing me fits... I'll come back to this thread and post some updated pics once I get it starting again. (Starter question in another thread.) Thanks again for the help!
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