Wolfcub, I feel your pain.
I have a 55 second series 1/2 ton with a 235, 4-speed and Langdon's dual C/Ws on an Offenhauser intake with Fenton split manifolds. It took months for me to sort these carbs out before this Barrett Jackson (read: overpriced), jewel of a truck could even drive around the block. Have you noticed they push them on and off the podium?
These carbs are not [b]"NEW"[/b], they are [b]UNUSED"[/b]. There is a big difference!
They are an emissions carb, originally for a 1983 Ford Escort 1.6 liter, manual trans car.
They may have been sitting in warehouses for [b]30 YEARS[/b]1. The gaskets are dry and brittle, the rubber diaphrams are aged and the dissimilar metals, aluminum, brass and copper have corroded and suffered from electrolytic action due to oxygen and variances in humidity.
Poor quality control during manufacture means lots of casting flash and debris inside the carbs as well.
I would like to kill whoever staked the air corrector jets and emulsion tubes and it wasn't Tom. These are emissions carbs and it was done at the factory so end-users couldn't change jetting and kill the Polar Bears.
As a result, these carbs must be disassembled and cleaned meticulously, and the gaskets and diaphrams replaced. Tom may say he cleans them, but this is impossible due to the staking of the jets.
You will destroy the heads of the air corrector jets when you remove them because of the staking and the fact that they are 30 years brittle. Don't beat yourself up over it. I have a Weber jet screwdriver and it still happens. You will likely have to use small vise-grips to get them out. The idle jets will come out easier and survive.
The air corrector jets are .150 on the primary and .250 on the secondary, I have a source that I will try to find and post later.
The carbs are simple to disassemble and don't need to be soaked, just clean them with spray carb cleaner and the tube. All you have to remove is the top float cover and the float.
The universal part exchange number for these carb kits is: [b]15787CF[/b]. Any decent parts man can still find kits.
Since it is a Ford application (turn head, spit) I use Motorcraft kits. The Ford dealer number is: [b]E3PZ-9A586-W[/b].
The Motorcraft number is: [b]CT-1377-A[/b].
Bonus! They are currently on clearance at Rockauto for $11.00 each!
Float height and drop are very important. Specs are here: http://pages.suddenlink.net/churchill_toolboards/Langdons%20Carter%20Webers.pdf.
Fuel pressure is also important, 6 lbs is way too much. Regulate it to 3 - 3 1/2 max.
Another important issue I found due to the age of these carbs is that the O-ring that seals the idle mixture screws can be hard and not seal or grip the mixture screw tightly. This is critical because the screw don't have an external spring on them like most do to hold them in tension. If your O-rings are shot they can leak air, upsetting your mixture, or worse, vibration can make them turn out, richening your mixture. Until I rebuilt my carbs I couldn't figure out why my mixture settings were changing. I thought I was loosing my mind!
Also, with most carbs your baseline mixture setting is 1 and 1/2 turns out from seated. With these carbs it is 2 turns out according to WEBER.
Here is the link for the air corrector jets and other parts for these carbs. They are based on the WEBER DFT.
http://www.piercemanifolds.com/product_p/77501.250.htm
Pictured is the secondary air corrector, P/N 77501.250,
the primary is P/N 77501.150.
The Pierce Manifolds site has good info and good exploded diagrams of the DFT.
Good luck.
Last edited by dwightlightning; 09/14/2014 4:29 PM. Reason: Added link.
