Tuning in 2bbl 352
Thread Starter
|
Freshman User
Joined: Oct 2011
Posts: 27
Likes: 0
Tuning in 2bbl 352
First off this is my first carburetor. I have a 66 f100 350 with a 352 ford carb #c6tf t. I rebuilt it tonight after taking it apart and soaking it in chem dip for a day. What are the adjusting screws on the bottom of the carb for? They have springs on them. I know that neither is the idle adjuster. Thanks for the advice. Also do you guys recommend using the lead substitute?
Tuned
Joined: Oct 2003
Posts: 386
Likes: 0
From: Wichita, KS
Those are the air/fuel ratio screws. screw them in all the way then out 1.5 turns. with the engine idling once warmed up then slowly adjust each one out until idle starts to drop (due to it being to rich) then screw back in 1 turn. at least thats how I was always told how to adjust them. good luck
Elder User
Joined: Apr 2008
Posts: 619
Likes: 1
From: Montpelier, VA
The mixture screws are for the idle circuit only. 1 & 1/2 turns out is a good rule of thumb for the idle mixture screws. Just don't over tighten them when you screw them in or you can damage the seat.
Posting Guru
Joined: Jan 2000
Posts: 2,281
Likes: 4
From: colbert washington
Old trick if you dont have a tach to use when making your adjustment was to put a half full glass of water on a flat surface on your motor and watch the water as you make your adjustment. Like I say a tach is better to use but the glass or water will do in a pinch. Sometimes your ear or sense of feel when adjusting the carb can fool you.
Thread Starter
|
Freshman User
Joined: Oct 2011
Posts: 27
Likes: 0
ok the carb is in, it works much better, but it still wont idle as low as I want it to, my guess would be that it's idling at 1200, anything lower it dies. Although when I have the choke on it idles great, probably 600-800. Any ideas? I tried all different adjustments with those screws.
Thread Starter
|
Freshman User
Joined: Oct 2011
Posts: 27
Likes: 0
Trending Topics
Elder User
Joined: Apr 2008
Posts: 619
Likes: 1
From: Montpelier, VA
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
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
Top 10 Ford Truck Tragedies
Joe Kucinski
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
Logistics Pro
Joined: May 2008
Posts: 3,670
Likes: 370
From: PHX AZ
Those are the air/fuel ratio screws. screw them in all the way then out 1.5 turns. with the engine idling once warmed up then slowly adjust each one out until idle starts to drop (due to it being to rich) then screw back in 1 turn. at least thats how I was always told how to adjust them. good luck
Use a vacuum gauge for highest vacuum or a tach for highest rpm.
Start off closer to 2 turns. Go back over each screw until you get the best idle.
For best emissions turn them out to highest vacuum then in until idle just starts to drop off.
Have you checked the points and dwell? (assuming you still have stock points system)
Where is your timing at with vacuum advance disconnected? Stock is 8 Deg before but they like 12+ BTDC much better for initial. Are you sure the idle circuits are all clean? Do you notice a big diff when turning Idle mixture screws?
Junior User
Joined: Aug 2011
Posts: 73
Likes: 0
If it runs ok with the choke partly or mostly closed it sounds like you have a very lean condition (too little fuel mixed with the air). Look for any large vacuum leaks. If the truck has a PCV valve, pinch off the vacuum line between the spacer plate and the valve to see if the idle improves. If the PCV valve goes bad it can cause a large vacuum leak in these trucks. If the PCV valve is OK look for other vacuum leaks with a can of carb. cleaner. When you spray an area with a leak it will cause the idle to come up and smooth out. If no leaks found, back the air fuel adjusting screws out as far as you can w/o falling out and see of idle improves.
Thread Starter
|
Freshman User
Joined: Oct 2011
Posts: 27
Likes: 0
Ok ill be checking for vacume leaks, the timing is another story. I installed a pertronics unit in the truck because the points were worn. That helped a lot. I have to do some more resedarch before I tackle timing it. I'm grabbing a vacume guage from work today.
Thread Starter
|
Freshman User
Joined: Oct 2011
Posts: 27
Likes: 0
well looks like im going to be pulling the motor. I have vacuum leaks around the intake manifold now three broken bolts on the exhaust manifolds and now the freeze plug under the motor mount ( the only one that I didn't replace) is leaking so I figure that i am going to save my self a lot of head aces if I just pull the motor. I ordered the felpro engine kit so i am going to replace all of the seals because i am sure that they are leaking. I'll be pulling the heads and replacing the head gaskets, and valve seals. I will also be inspecting all the bearings while im in there and maybe do the rings.
What else should I be doing while I have the motor pulled? Is there anything that I need to be aware of before I tear into it that is special to these old trucks?
What else should I be doing while I have the motor pulled? Is there anything that I need to be aware of before I tear into it that is special to these old trucks?
Thread Starter
|
Freshman User
Joined: Oct 2011
Posts: 27
Likes: 0
Ok, so the motor is finally in. Still having some idling issues. The pcv valve is new, The timing is set at 10. It will still only idle in choke. and it wont idle very low there. I don't have any vacume leaks. I set the timing with the vacume advance disconnected and the hose plugged. The fuel air mixture screws don't seem to do much of anything. Even with the idle screw all the way in it still wont idle with out the choke. I can push the choke about 50 percent of the way in before it idles down and dies. Any help would be great.