Both 94s sinked at 20kg/h at idle

[RandyMettler]

I can not get the kg/h below 20 or the car stalls. 20kg/h will open both 3.5 power valve at idle. My car goes through a gallon of gas in 15 minutes at idle. Starts easy when cold. Does not like to start even with only a couple of minutes of idling. I checked spark/good, but only with the sparkplug removed and cleaned. I checked fuel delivery/good. My plugs are soaked in gas. I have a 8BA, dual 94s 3.5 power valves, 47 jets, non progressive linkage, new air filters, new plugs, new plug wires, crab ignition just serviced, valve lash just set, just installed a fuel pressure regulator, just installed a Charlie Ny fuel pump, just rebuilt my 94s. I am guessing my power valves are functioning as designed. Why 20kg/h at idle? Turning my crab left or right seam to have no effect on idle. Turning my idle mixture screws in and out has no effect what so ever unless I turn them all the way in. I unscrewed the intake manifold plug to relieve the vacuum pressure. That did not have any effect on the snail readings, only made the car backfire. It has to be something simple? I can stand by the motor and hear the 94s sucking air, way too much, but I am probable mistaken.

Regards

[Flathead Fever]

Your back. That's no good, your washing the oil off the cylinder walls and contaminating your oil. You probably have a power valve leaking. With the engine off open the throttle plates all the way and look down in there to see if the fuel is leaking into the intake manifold.

[drolston]

Did Charlie also rebuild the 94's, or just the fuel pump?
In any case:
1) check the fuel pressure. Anything over 3 psi might be pushing by the float valves and flooding the engine.
2) one of the float valves may not be sealing properly; a bit of debris from installation could be the problem. Remove them and blow some carb cleaner through them. Or better, replace them with the Grosse type (steel ball instead of pointy needle piece)
3) one of the floats set too high. Unlike 97's, setting floats on 94s is tricky business.

Report back.

[RandyMettler]

drolston,

Thank you for your input. This had been happening since I purchased the car. I have rebuilt the 94s twice. I have installed a fuel pressure regulator and set it at 1 psi, no change. The float power valves are definitely not sealing, the vacuum pressure is holding them wide open at idle. This is all just what I have learned from the help of all you barners out there and my tests.

[Tinker]

I'm confused, previous thread you said you got it worked out? Not so?

[RandyMettler]

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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.

[RandyMettler]

Tinker;

"I'm confused, previous thread you said you got it worked out? Not so?"



Last night it was idling great and carbs sinked at 20. The revees were smooth, but understand, I only test for a short period of time. Hoa's, aging neighbors that are always home and duals glass packs and a flathead (loud). I believe Gas turns everything to XXXX after running for a few minutes.

[Tinker]

As mentioned check pv's, float settings, or your needle seating.



...or buy a couple 97s. and get them setup for duals


Could run a single 94 till you get one sorted out then move to two. New engine and managing two carburetors can be tough. Get it running then upgrade.


or not. Just a suggestion.



quote" I only test for a short period of time. Hoa's, aging neighbors that are always home and duals glass packs and a flathead (loud). I believe Gas turns everything to XXXX after running for a few minutes."


Had a 4hp witte oil field throttler that sounded like a shotgun going off every time it fire. At the time I lived downtown, so I threw a couple tractor mufflers on it. Lucky I had one neighbor that like the sound of v8s/engines.
https://www.youtube.com/watch?v=YsVnPdRjCU4







.

[51 MERC-CT]

What is this (20kg/h) reading you are getting and how does it translate to the common (in.-Hg) or (mm-Hg)?

[RandyMettler]

":I can not get the kg/h below 20 or the car stalls". To me this indicates that the motor is tying to compensate for the tremendous amount of gas that is going down the carbs. The stalling when I mechanically reduce the rpms by closing the throttle plates and attempt to reduce air flow is a result of the plugs being soaked it gas/ engine stall. I could be wrong, new at flatheads

[Tinker]

See Bruce's post#6
https://www.jalopyjournal.com/forum/...ziness.971853/

[RandyMettler]

51 MERC-CT
"What is this (20kg/h) reading you are getting and how does it translate to the common (in.-Hg) or (mm-Hg)?"


It translates mathematically to in-Hg slightly less than 4 times than what I am reading. So mathematically speaking, I am running 5 times more air down my horns than ford designed. This will pull fuel out of the carbs as needed. Pure suction/vacuum, I believe the mechanics that keep the engine from reeving high as it should, is the carbs pouring the fuel down the cylinders.

[Tinker]

That's without linkage and butterflies closed?


Send your carbs off.

[RandyMettler]

I had to sink the carbs. In order to do that the throttle plates had to be adjusted slightly opened to balance air and fuel. The carbs would not sink otherwise, I believe the power valves are also wide open due to the air flow meter readings feeding the engine, this is with the linkage off as suggested. They should sink at 4 not 20. This is because the carbs are sucking so much air. When I try to restrict the air the engine stalls, too much fuel. I believe it is not a carb issue, it is something much worse.

[Tinker]

Well a combustion engine is really just an air pump.


You have something going on I guess. Look forward to your progress.


Best of luck!




.

[Mike in AZ]

1 psi from pressure regulator verified by a gauge? “Turning crab”? What kind of air filters? Mike

[RandyMettler]

Mike in AZ, in response to your help
"1 psi from pressure regulator verified by a gauge? “Turning crab”? What kind of air filters? Mike"

I have a fuel pressure regulator. I have it set 3.5 psi. I have turned it as low as 1 psi with no change. My "crab", is my distributor, it is a crab style not typical for 8BA'S. I have the typical cheap dual 94 air filter and are both new. The key thing here is my engine has abnormal sucking sucking sound. It will almost break your hand if you cover one of the carbs. Both carbs will almost break your hands if covered.

[chap52]

Randy, I had a EAB running dual 94's and Charlie NY advised me to plug off the Power Valves. He has machined PV plugs for this purpose. After doing so I was able to balance the carbs with a Uni-sync. I know vacuum is a finer adjustment but didn't have a gauge. Also found that the teapot air filters I originally had would cause the engine to "choke out" and stop. Went to just air horns (?) with screens and thin foam filter and all worked out great.
I would ask him his advice. Charlie's e-mail= [email protected]

[scicala]

All I can say is you will be better off if you find someone to set up your carbs that has done it before. Your 20 kg/h at idle has nothing to do with manifold vacuum (hg). If kg/h is what the unisync measures, and is pegged on the high side, the only way to reduce it is to back off on the speed screws on the carbs, not the two mixture screws.
I'm pretty confident the power valves are not open at idle. It is possible the small diaphragms in them are ruptured and leaking though.


Sal

[Black Fifty]

Originally Posted by scicala

All I can say is you will be better off if you find someone to set up your carbs that has done it before. Your 20 kg/h at idle has nothing to do with manifold vacuum (hg). If kg/h is what the unisync measures, and is pegged on the high side, the only way to reduce it is to back off on the speed screws on the carbs, not the two mixture screws.
I'm pretty confident the power valves are not open at idle. It is possible the small diaphragms in them are ruptured and leaking though.


Sal

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?


Mike

[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

[flatjack9]

Originally Posted by Tinker

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 a



.

I'm not understanding your comment concerning 7.5". The power valve sees whatever vacuum the engine is producing. If the vacuum is 17", each power valve sees that amount.

[flatjack9]

Originally Posted by 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?


.

Actually air flow is caused by atmospheric pressure.

[Black Fifty]

Originally Posted by 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?

The uni-syn is measuring mass air flow and giving you the result in kg/hr. You can convert that to "cfm" and that also tells you how much air is going into the engine while idling. I found a formula that converts kg/hr to cfm by multiplying your flow number by 2.08. 2.08 x 40 (carbs combined) tells you that the engine is getting 83.2 cfm at that engine speed. Or 41.6 cfm per carb. I would guess that having that "balance" makes for better volumetric efficiency of the engine by maximizing the likelihood that you'll get the same amount of air into each cylinder (in a perfect world).



Just my two cents.

Very interesting discussion too.
Mike

[Tinker]

Originally Posted by flatjack9

I'm not understanding your comment concerning 7.5". The power valve sees whatever vacuum the engine is producing. If the vacuum is 17", each power valve sees that amount.

Yes. When vacuum is below 7.5" the pv opens on a single holley94. 2 carbs split the number or close. My understanding.



More nonsense to add...

https://www.jalopyjournal.com/forum/...-valve.798600/

[Tinker]

Originally Posted by flatjack9

Actually air flow is caused by atmospheric pressure.

A flathead sitting has no atmospheric pressure on it, till it runs creating flow/pressure. But like blowing through a straw if you don't put your finger over the end then no pressure is made either.

I do have a barometer in my house though.






.

[flatjack9]

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Originally Posted by Tinker

Yes. When vacuum is below 7.5" the pv opens on a single holley94. 2 carbs split the number or close. My understanding.



More nonsense to add...

https://www.jalopyjournal.com/forum/...-valve.798600/

2 carbs do not split the vacuum. If the vacuum is 7.5" they both see that number. Standard power valves are rated at 7.5". When you install 3.5 power valves, that is where they will open.

[flatjack9]

Originally Posted by Tinker

A flathead sitting has no atmospheric pressure on it, till it runs creating flow/pressure. But like blowing through a straw if you don't put your finger over the end then no pressure is made either.

I do have a barometer in my house though.






.

This must be a new science. What does that barometer measure?

[Tinker]

Originally Posted by flatjack9

This must be a new science. What does that barometer measure?

Your sarcasm is not lost.


but just encase.
https://www.youtube.com/watch?v=i2UKTpIQG6M


https://www.youtube.com/watch?v=4K_XJGuRy88


neat version
https://www.youtube.com/watch?v=EkDhlzA-lwI

[Tinker]

Originally Posted by flatjack9

2 carbs do not split the vacuum. If the vacuum is 7.5" they both see that number. Standard power valves are rated at 7.5". When you install 3.5 power valves, that is where they will open.

Yes, being there is twice the air flow, 2 carbs vs 1. Like having two holes in a dam. So vacuum decreases quite quickly. Needing pv's that open at lower vacuum.


An engine that is working well at 18-20" vacuum at idle. Once you accelerate, it decreases engine vacuum. One carburetor only lets so much air flow through the engine. Two carburetors add more flow, etc. More flow less and less vacuum. Vacuum shared by each pv or carb.


pv's on 94s are reverse thinking. They close under vacuum and open under low vacuum conditions. Not a fan.




.

[Black Fifty]

neat version
https://www.youtube.com/watch?v=EkDhlzA-lwI


Now I see why so many hot rodders lower their cars. The pressure pushing down into the carbs will be higher at lower elevation. Fascinating!