Both 94s sinked at 20kg/h at idle

[Black Fifty]

What rpm is it running at during all of this, Randy?

[scicala]

"Sal,
I think he's using the uni-sync to adjust flow rate through the carbs, therefore it's measuring kilogram/hour. When adjusting the mixture you would monitor manifold vacuum, right?"




Yes, that's how I understand it too. You have to get both carbs with the same unisync reading to attain the idle RPM you desire. Then adjust the idle mixture screws for the highest vacuum/smoothest idle. You don't shoot for the highest unisync reading.


Sal

[flatjack9]

You need to know manifold vacuum.

[JSeery]

Randy, there is really no way you are going to be able to sync the carbs if they are malfunctioning. You need to get the cabs up to speed first. Best bet is to send them to one of the rebuilders, you will have them back in no time and then work on syncing them.

[RandyMettler]

Black50, in response to your question:
"What rpm is it running at during all of this, Randy?"

Black50
I don't have a tach so I can not tell you the exact RPM numbers. Basically after I adjusted the 94 with the linkage off, one at a time, with the synchronmeter, I focused on the rpm screws. The lowest I could get the airflow readings were 20kg/h. I originally had one carb pegged and one at around 14. The adjustments seemed to split the difference in airflow between the two, which ended up at 20kg/h. That number did not seem negotiable. I played around with the RPM screws to get the idle to sound correct. My concern was or is 20 too high? After I focused idle mixture screws. They didn't have as much effect on the idle as I had hoped, but the car idles smooth and constant. I then reconnected the linkage and focused on the timing. The car occasionally has a slight misfire when throttled but not always. If you throttle a couple of times in a row it only misfires out the tailpipe at first throttle. I will get a timing light on it as soon as I can. The concern is it really does not like to start after say 10 minutes of test running. It could be the carbs or the timing. I was turning the distributor slightly, both directions from my tape marking rotor alignment to #1 cylinder. Distributor adjustment was done with the car off. I was hoping when I got close to the correct adjustment the car would begin to start easier. This did not happen.

Regards

[Flathead Fever]

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Originally Posted by RandyMettler

Flathead fever, yah the garage reeks of raw gas. I am sure the power valves are open but cannot figure out why my vacuum/airflow readings are almost pegged? It has to be obvious with these symptom's but I don't know.

We need to start all over from the beginning. I'm getting confused? Were going to do one or two things at a time.

Did you ever look down in the carbs to see if they are leaking when its not running? If its a leaking power valve you would see it with the engine off and the throttle plates open.

I don't trust most of those aftermarket add on fuel pressure regulators. Is this an electric fuel pump or a mechanical one. If its mechanical pump you should not need a pressure regulator. If its electrical, with the pump running, look in the carbs to see if they are flooding over. There should be no fuel coming out of those carbs.

[RandyMettler]

Flatheadfever, in response to your help:
"We need to start all over from the beginning. I'm getting confused? Were going to do one or two things at a time."


Flatheadfever,
I have looked down the carbs with the motor off but only before starting and saw no fuel but I believe the throttle plates were closed. To open the throttle plates I need to push the linkage. When doing this I get fuel jetting out of the pump discharge nozzle. I could disconnect the linkage an do the test.

I am proud to say I have a Charlie NY mechanical fuel pump. I only use my in line electrical pump to prime before starting. I understand in vapor lock situations an electrical inline fuel pump can help in starting, but haven't tested that yet.

If the power valves are leaking they should always leak. I can pull the main body off the carbs throttle body and look for wet gas. I did that today on the secondary carb and the carbs throttle body was dry. I am contemplating plugging the power valves but have heard both sides of the story. I really would like factual information either way. Some guys swear by it others are against it. My thoughts are fuel starvation could happen at load conditions and cause excessive piston wall wear. On the other side the 94 are notorious for dumping excessive gas down the pistons. I understand the 94s have three separate fuel circuit. Maybe two is enough? I could not find Youtube information of this.

I always appreciate advice. If I am way off please let me know, but explain why.

[Charlie ny]

Randy I've made offers to you to build the carbs so they work. Your motor is getting washed away in excess gas. If you send the carbs to me ,at your convenience, you
won't need your sync gizzmo. I'm serious when I tell you my schedule is filling up
fast.

The pump I did for you worked right out of the box.........right ?

If you don't like me send the carbs to Sal, he's # 1 in my book !!


Charlie ny

[RandyMettler]

Charlie ny,

The pump you sent me works great. The oil level is not rising anymore. I bought this car to restore so I am spending a certain amount of time working on it and learning. I am not a take my car to a mechanic type of guy. I grew up having to fix my own cars. I am trying to work out the carbs situation to see if the 94s are really the problem and not just my lack of understanding and installation adjustment. I am close to sending the carbs to you and fully trust you will solve any issues they have. I do apricate your advice that I may be harming my motor through my diagnostic process. That thought has definitely crossed my mind. There is one thing I have found I like about fordbarn, the senior members don't hold back when they see you are being dense and are standing in your own way.

Even after you fix them, don't they still need to be sinked? Isn't it a function of adjusting the throttle plates to get the carbs airflow equal?

Thanks for your help with the fuel pump, as far as I am concerned you are the man.

Regards

[Flathead Fever]

Read this article. You might need to change the power valves to ones that open with less vacuum.


https://www.hotrod.com/articles/0510...ge-carburetor/

[RandyMettler]

Thanks for the link Flathead Fever. That link is why I changed my power valves to Charley Price 3.5's. The internet is a wonderful thing. I just wish there was a little more out there on flatheads. Thank god for fordbarn! Tomorrow I am going to start making arrangement to send my 94s to Charlie ny. I hate to be defeated, but I have beat this horse into the ground. Jello anyone?

Regards

[Tinker]

Originally Posted by Flathead Fever

Read this article. You might need to change the power valves to ones that open with less vacuum.


https://www.hotrod.com/articles/0510...ge-carburetor/

To my previous understanding and talks. There is/are 3.5 pvs installed, which is typical. Two 94 carbs share the pv vacuum and should equal 7.5in, Give or take. Less then half total vacuum of 18-20in at intake at idle. Low vacuum to properly open pv's and to "flood" gas, under-load or add fuel at speed (when the butterfly's are at their most open and draining the engine of inner vacuum/air) ...hence is when vacuum is low and fuel is needed. If all is working well... To my understanding anyway.


If initial engine vacuum at intake is too low. 94 pvs will open which allowing them to flood out an engine.


Thinking something else might be going on here also. Or not.




.

[RandyMettler]

Tinker, In response to your comment, "Less then half total vacuum of 18-20in at intake"

I am sending my 94s to Charlie. Your comment is what I have been mentioning previously. I am getting 20 at each carb simultaneously. I would think that would dictate I have a total of 40 intake vacuum which would be twice what is normal? Still learning all this. Vacuum and the throttle plate position is what draws fuel from the carburetors? (Air fuel mixture). If I have twice the vacuum would I be drawing twice the fuel?

[Tinker]

Not sure where you are getting your readings but...



If you have solid needles and everything is setup correctly. Fuel will not be effected by vacuum other then 94 pvs. My understanding anyways on 94s.

[Tinker]

That vacuum reading is taken off the intake/engine, after the carburetor. Not before or at the air horn.


sync is to equalize the carburetor air flow between the two. if your butterflys are releasing too much airflow your "inner" engine vacuum will suffer. Its all the same thing.

[RandyMettler]

My readings are coming from the "snail" synchometer budda recommended I purchase. I have solid needles at idle adjustment screws and solid needle at my needle and seat. So what I am getting is more vacuum is better. More is always better.

Okay you are referring to the intake manifold reading not the carburetors total air flow. This has been stated to me more than once but the difference not explained. I apologies if my experience is a bit trying.

[Tinker]

I've probably have not been very good at explaining either.

Have you put a vacuum gauge on your intake yet? Vacuum is created in the engine, airflow or air brought into the engine is needed to create vacuum within. Both work together, but are very different.

Send your carbs to charlie or someone. You'll still have plenty to work on with decent carbs to start with.

[RandyMettler]

I get it, vacuum can be created without air flow but without the presents of air it will stall the motor. Spark, fuel, air. I have plenty of spark, plenty of fuel and plenty of air, the carbs aren't doing their jobs. That's all your guys had to say, HAHA!

[Tinker]

Nope, Vacuum can only be made with air flow. There is no vacuum with the engine off.


Vacuum drops when the engine has too much airflow. or when there is a leak, bad valves seating, or butterflies are open.


Make sense?


.

[chap52]

Looking forward to hear how those carbs do after Charlie does his magic on them. Good decision, Chap