Gasoline

Noticed that the Accelerator Pump Cover arm is bent to the left. Strange and I donīt know if I have caused this when fixing the carburetor or if previous owner did this for a reason.

Forgot to mention that there is no change during idle with the fuel in the filter if the fuel cap is removed.

kalli

change the pump diaphragm if you're at it alright. the accellerator pump has to work in such a way that when warm the slightest dab on the throttle actuates the pump
to check (with car warm and choke disengaged, engine off), see if there is up-down movement at the actuator for the pump cam. there must be no gap, movement between what you adjust with the springs and the lever from throttle. so no up-down movement on the spring thing. of course if you force it you can shove the lever down. a little left-right, forward backward movement is ok.
then open the throttle fully, hold it there or block it. then you must be able to further push in the pump by another millimeter or so. it doesn't really matter how much, just as long that full WOT doesn't cause the pump to be completely engaged, there must be a tiny bit of travel left in the pump.
once set you should have a steady stream of petrol in both front bowls of petrol as you open the throttle. don't forget to remove anything you might have used to jam the throttle wide open for measurement

Gasoline

Hello again!

I have been testing and tuning all wekeend and I think I can be more specific this time.

I changed the acclerator pump diaphragm, cover and umbrella and the result was positive, but there is still a problem during steady speed. I also tested all the springs to the secondary again.

There is a heavy bog that occurs during steady speed and disappears if I accelerate more, but if I cruise or drive normally the car seems to be stuck in this "bog mode". Is it the power valve opening? I thought it was the secondary before. It is not directly from idle and occurs at all speed if just I dont push the pedal hard enough. But then again it is hard to just cruise and drive legally if I push the pedal to hard.

There is no bug if I push the pedal slightly. My vaccum is 15 at 1000rpm and I use a 6.5 power valve.

Anyone?

Gasoline

Hi!

I think I can close this thread by saying that changing power valve from 6.5to 5.5 did the job.

Have a look at this thread: http://www.fordmuscle.com/forums/all...on-needed.html

Have a nice summer!

Thomas

Gasoline

Forgot to mention that I also adjusted the float level. I have plastic floats so I used this link as a guideline.

http://www.holley.com/data/TechServi...Carburetor.pdf

That probably was the problem in the first place.

kalli

fuel level too low will cause it alright. good to hear you got it sorted

Gasoline

Yep, and the problem with the fuel filter not filled with gas was probably caused by air in the system.

It dissapeared after I removed the fuel line from the carb and placed it in a glass jar and cranked the engine a few times.

Norm Peterson

About halfway down I was thinking power valve. Maybe the next question should be "why does it need a 5.5?". Do you have a rather lumpy cam?

Those clear fuel filters are very apt to not be airtight.


Norm

valley firearms

It sounded like it was a lean spot at first. Glad you figured it out.

67mustang302

^ This

5.5 is awfully low for a PV unless it's got a pretty nasty cam.