Carb issue
Thread Starter
|
Laughing Gas
Joined: Mar 2015
Posts: 885
Likes: 2
From: Pittsburgh
Carb issue
Newer with the whole carb thing but just finished my first rebuild. I got it back on and it's already running better. But when I went to tune I noticed some issues and ended up pulling it again
1.) I can't drop my idle below 1000, curb idle set screw is completely backed off the throttle plate but they won't close any further to drop my idle and yes it's fully warmed up.
2.) fast idle cam won't move at all. I can't move it with my finger and it won't drop when I simulate hitting the throttle.
Any ideas? I'm thinking these things are probably one issues giving me two problems.
1.) I can't drop my idle below 1000, curb idle set screw is completely backed off the throttle plate but they won't close any further to drop my idle and yes it's fully warmed up.
2.) fast idle cam won't move at all. I can't move it with my finger and it won't drop when I simulate hitting the throttle.
Any ideas? I'm thinking these things are probably one issues giving me two problems.
Thread Starter
|
Laughing Gas
Joined: Mar 2015
Posts: 885
Likes: 2
From: Pittsburgh
Ok I figured out the curb idle issue...the throttle plates won't close any further because the fast idle cam screw is stopping on the fast idle cam. Which still brings me to problem number 2...fast idle cam won't move.
Any help would be greatly appreciated I'm gonna be at this all night.
Any help would be greatly appreciated I'm gonna be at this all night.
Thread Starter
|
Laughing Gas
Joined: Mar 2015
Posts: 885
Likes: 2
From: Pittsburgh
Yeah that's what I'm trying. I'm reading some really good instructions from another post. The problem is that the metal piece with the notched "V" will not move at all. That's where I'm "stuck", pun intended.
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
Hm, are you sure the throttle plates aren't binding on a gasket or spacer or something?
Linkage is free? Have an assistant floor the pedal. The butterflies should be perfectly vertical. The important thing is that the throttle should be almost completely closed at idle, and only the idle circuit in play. Only T slot exposed, like this:
Sent from a pay phone
Linkage is free? Have an assistant floor the pedal. The butterflies should be perfectly vertical. The important thing is that the throttle should be almost completely closed at idle, and only the idle circuit in play. Only T slot exposed, like this:
Sent from a pay phone
Thread Starter
|
Laughing Gas
Joined: Mar 2015
Posts: 885
Likes: 2
From: Pittsburgh
Thanks for the replies. Throttle plates move fine and I didn't disassemble them for the rebuild so they should be lined up fine but I'll have to check.
I broke the idle cam free with much effort and PB blaster. I guess I should've checked functionality before that rebuild, still new at these
I broke the idle cam free with much effort and PB blaster. I guess I should've checked functionality before that rebuild, still new at these
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
Have a vacuum gauge yet? You really need one to tune older motors and carburetors. Here's a couple links on how to avoid the most common errors (hardly anyone does this, many if not most, carbs are not setup correctly to begin with)
What's nice is once they are setup they don't need much attention after that. Don't let the gas go stale in tank or carb, that will screw all kinds of things up however. Replace ALL rubber hose in the fuel line, and use new clamps. Even better, bend your own hard line so there isn't any potential fuel line leaks near hot exhaust manifold.
http://www.junkyardgenius.com
http://www.junkyardgenius.com/holley/tune01.html
What's nice is once they are setup they don't need much attention after that. Don't let the gas go stale in tank or carb, that will screw all kinds of things up however. Replace ALL rubber hose in the fuel line, and use new clamps. Even better, bend your own hard line so there isn't any potential fuel line leaks near hot exhaust manifold.
http://www.junkyardgenius.com
http://www.junkyardgenius.com/holley/tune01.html
Trending Topics
Thread Starter
|
Laughing Gas
Joined: Mar 2015
Posts: 885
Likes: 2
From: Pittsburgh
Yeah I used the vac gauge to set the idle mixture screws. I'm still having a slight issue but I think it's due to the electric choke at this point. Nothing will open the choke fully except holding it open with my hand. Positive wire to the choke has voltage and if I pull it the voltage travels through the coil spring but it doesn't move much. Fast idle cam isn't interfering with it so I think I'm gonna throw a new electric choke at it. At this point if the choke was manual I'd have no issues left.
I was able to get everything else set. Fast idles at about 1100, curb idles right at 650. Fast idle cam appears to be working fine now after much lubrication.
I'll check out the link though, but on another post here I found an amazing write up that also included many things typically overlooked.
I was able to get everything else set. Fast idles at about 1100, curb idles right at 650. Fast idle cam appears to be working fine now after much lubrication.
I'll check out the link though, but on another post here I found an amazing write up that also included many things typically overlooked.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Thread Starter
|
Laughing Gas
Joined: Mar 2015
Posts: 885
Likes: 2
From: Pittsburgh
Well I ordered a new electric choke for $40 from AutoZone. If it doesn't fix my problem I'm going to return it and go with a $10 manual choke. I'd kind of rather do the manual choke to be honest but I am trying to keep this as stock as possible and don't really feel like messing with drilling, mounting, and running everything as it gets colder outside.
The problem is most likely a worn-out 37 year old factory carb but the only thing the rebuild didn't fix is this choke issue. I'd hate to spend $300+ on a new or reman when I can just do the $10 manual kit.
The problem is most likely a worn-out 37 year old factory carb but the only thing the rebuild didn't fix is this choke issue. I'd hate to spend $300+ on a new or reman when I can just do the $10 manual kit.
Thread Starter
|
Laughing Gas
Joined: Mar 2015
Posts: 885
Likes: 2
From: Pittsburgh
So I put the new choke on and after warming the truck up thought that my problem wasn't solved because the choke hadn't moved. Then I realized I forgot to hook the power wire back up. Once I did that it worked fine. But I'm still confused...
Why do these trucks have a connection to exhaust heat as well as a power wire? I know that some trucks only have the electrical connection and I understand how that portion works, not to mention it seems to be the only thing that makes mine move...but why won't my exhaust heat make the choke spring open? Is there some other problem that's gonna screw me up down the road?
Why do these trucks have a connection to exhaust heat as well as a power wire? I know that some trucks only have the electrical connection and I understand how that portion works, not to mention it seems to be the only thing that makes mine move...but why won't my exhaust heat make the choke spring open? Is there some other problem that's gonna screw me up down the road?
Thread
Thread Starter
Forum
Replies
Last Post
gudor
1973 - 1979 F-100 & Larger F-Series Trucks
1
Apr 1, 2012 12:31 PM
76supercab2
Fuel Injection, Carburetion & Fuel System
15
Jul 18, 2006 02:55 PM