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You only need one line for the pcv valve. One thing I did notice that may or may not contribute to your fuel leakage are 2 missing machine screws on each carb that hold the base plate to the main body. I've heard that on some newer Hollies that these screws were eliminated. Not knowing the age of your carbs I'd look into it. If it were me though and the holes in the main body are tapped I'd put them in and don't forget the split lock washers. The only hole that normally doesn't take a screw is the one in the middle of the base plate.
Other options you might want to consider after you get the motor dialed in is the tuning of the secondary opening. Holley makes makes spring kits to change when your secondaries open and you may also want to consider changing the tops of the secondary housings to the ones with a nipple so that they can be inner connected with a piece of vacuum line to insure they both are getting equal vacuum and opening at the same time. While you have the carbs off would be a good time to pull the power valves out and check their rating. If they are standard valves they probably are not opening when they should be. There are lots of videos on line that will give you step-by-step instructions on how to do these things if you've never done them before. One last thing is to check your accelerator pump actuator cam profile, position and also the adjustment of the screw that moves the accelerator pump arm.
 

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Dave while the carbs are off you need to see what powervalves are in there. Did you say these were rebuilt? Do you trust the builder? Just curious what cam you have in the motor duration wise. You could have a bad power valve or one that is too high in number in both carbs making them gas hogs. If the carbs are not progressive pull the power valves and replace with plugs.
Before you do anything else do yourself a favor and check the firing order. There is not one among us who has not crossed a wire and blamed the carburetor for bleeding down just wanted to make sure you were aware of that.
Keep at it buddy.

steve beat me to the power valves.
 
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Discussion Starter · #604 ·
Dave while the carbs are off you need to see what powervalves are in there. Did you say these were rebuilt? Do you trust the builder? Just curious what cam you have in the motor duration wise. You could have a bad power valve or one that is too high in number in both carbs making them gas hogs. If the carbs are not progressive pull the power valves and replace with plugs.
Before you do anything else do yourself a favor and check the firing order. There is not one among us who has not crossed a wire and blamed the carburetor for bleeding down just wanted to make sure you were aware of that.
Keep at it buddy.

steve beat me to the power valves.
Hi Mario and guys, I trust the builder. He is a class winner at Brainerd. And he fires up every carb he rebuilds on a test mule in his garage. I just wonder if things just plain went bad after 2 moves and not being used for 2 or 3 years. I will take these things apart tonight and see whats up in there.

where does the other carb get its vacuum from? I guess I am confused by that.

1 line goes to the distributer
1 big line goes to PVC
1 line to the transmission.

Also, which gasket, open or 4 hole?
 

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Hi Mario and guys, I trust the builder. He is a class winner at Brainerd. And he fires up every carb he rebuilds on a test mule in his garage. I just wonder if things just plain went bad after 2 moves and not being used for 2 or 3 years. I will take these things apart tonight and see whats up in there.

where does the other carb get its vacuum from? I guess I am confused by that.

1 line goes to the distributer
1 big line goes to PVC
1 line to the transmission.

Also, which gasket, open or 4 hole?
Not sure what you mean by one carb getting vacuum from?
do you have a pvc valve on the hose?
 

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Hi Mario and guys, I trust the builder. He is a class winner at Brainerd. And he fires up every carb he rebuilds on a test mule in his garage. I just wonder if things just plain went bad after 2 moves and not being used for 2 or 3 years. I will take these things apart tonight and see whats up in there.

where does the other carb get its vacuum from? I guess I am confused by that.

1 line goes to the distributer
1 big line goes to PVC
1 line to the transmission.

Also, which gasket, open or 4 hole?
Since you're running a tunnel ram and most have a non divided carb mount opening use the open gaskets. Obviously if you only have a couple that are divided, cut out the dividers. I'd still recommend checking about the 2 missing machine screws in each carb. That could be another contributing factor to your fuel stains around the base of the carbs. You can always call the Holley tech line. It doesn't matter how many carbs you're running; 1, 2, 4 or six they all pull vacuum from the same place, the intake manifold. Make sure you don't attach your distributor advance line to a manifold vacuum port on the carb, you want to use the "timed" port; the one that shows no vacuum at an idle. The line to your trans modulator valve should be hooked to a manifold vacuum nipple on one of your carbs.
 

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Discussion Starter · #607 ·
what I mean is since both carbs vacuum secondary carbs, where do I get the vacuum for both carbs from? specifically the large input on the carb.
 

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what I mean is since both carbs vacuum secondary carbs, where do I get the vacuum for both carbs from? specifically the large input on the carb.
The carbs get their vacuum automatically from the intake. Not like you need a line connected somewhere to feed them. The lines (both small and large) are outputs to other devices like brakes, transmission, or vacuum advance. None of them feeds vacuum into the carb, but rather pulls vacuum to those other devices.
As Steve mentioned a vacuum balancing kit helps a lot to time both carb's vacuum together so at wide open throttle they open simultaneously. And they come with springs in the kit to set when you want them to open also.
 

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Discussion Starter · #609 ·
The carbs get their vacuum automatically from the intake. Not like you need a line connected somewhere to feed them. The lines (both small and large) are outputs to other devices like brakes, transmission, or vacuum advance. None of them feeds vacuum into the carb, but rather pulls vacuum to those other devices.
As Steve mentioned a vacuum balancing kit helps a lot to time both carb's vacuum together so at wide open throttle they open simultaneously. And they come with springs in the kit to set when you want them to open also.
Man, I feel so stupid. I just do not get these things. I am going to open them up, wee if anything looks out of the ordinary and start from scratch. I saw a good video from Holley on how to get a good baseline going.
 

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Man, I feel so stupid. I just do not get these things. I am going to open them up, wee if anything looks out of the ordinary and start from scratch. I saw a good video from Holley on how to get a good baseline going.
Hey never feel stupid. Your getting a hotrodding apprenticeship from top notch guys. Look at all the replies and walk away with a wealth of knowledge. These guys are top notch. We all learned the hard way. Benefit from it. You’ll get there just be patient. Holley screws are on ebay or Amazon.
And remember if someone else builds a carb and tests it on their motor It doesn’t mean it will be turn key on yours. Angle, float levels, power valves, nozzles and jetting Can vary. In storage the accelerator pumps can dry out and leak. So can the power valves if they have one. Did you know that needle and seats come in different flow levels? There is a number stamped on the brass housing up top behind the lock nut. Look at one carb at a time. Don’t open up both with parts all over. Let us know what jets are in there too. Don’t rush.
to be continued.………
 
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The carbs get their vacuum automatically from the intake. Not like you need a line connected somewhere to feed them. The lines (both small and large) are outputs to other devices like brakes, transmission, or vacuum advance. None of them feeds vacuum into the carb, but rather pulls vacuum to those other devices.
As Steve mentioned a vacuum balancing kit helps a lot to time both carb's vacuum together so at wide open throttle they open simultaneously. And they come with springs in the kit to set when you want them to open also.
Here's a photo of my old cross ram setup showing the vacuum balance line between the 2 vacuum secondary carbs and a photo after I changed to dual feed, double pumpers. Then I went to the Ford tunnel wedge manifold (and I used the 2 large vacuum ports to install a vacuum gauge) what a difference in performance.
Motor vehicle Automotive lighting Hood Automotive tire Automotive fuel system



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Discussion Starter · #612 ·
Thanks flor the support guys. I think my first issue is to see what is leaking and then start over. to be continued is right!
 

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Dave, you're asking great questions, and only stupid questions are the ones not asked. Some people are afraid to ask, and struggle because of it, so don't worry about asking any question. It might save you some time and headaches later.
I had the same vacuum kit to connect my carbs as Steve, and changed secondary springs to allow for earlier openings on my BBC in the Falcon.

 

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Dave I found these on Ebay. If you need them.
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Discussion Starter · #615 ·
Thanks! We have a speed shop 9 miles from me and I drove over and got some bolts. Friday night and Saturday was spent cleaning up each carb. I took off some parts, cleaned them up and on sunday, I put two gaskets on and set everything back to a video I saw on YouTube. gas and air are 1.5 turns out, idle set was all the way out then 1 turn in. pretty tame I guess and then I turned the fuel pump on, filled the bowls and checked the float level. Turns out it is just right like the guy in the video. If I rock the car, it trickles out of the hole. so far so good. Then I started it. it shot to 4k on the tach and stayed there. I shut it off immediately and went to see if the throttle cable was too tight. so I tried it again after taking the idle set screw all the way out. started again and it went and stayed at 3k this time. then I took the gas pedal cable off. still at 3K. The only real thing I did differently this time was to add the vacuum line to the distributor. the un-used vacuum plugs are blocked. Ideas?
 

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Both carbs need to be closed. If the blades are open in either it will bring the idle up. All the vacuum ports are plugged? What jets were in the carb primaries? What power valves were in there?
sounds like your floats are good adjustment.
my first thought is that you have a vacuum port that is open like the one that would go to the PVC valve. Do you have them all plugged so they don’t leak. Next is I would look at the vacuum ports on the side of the metering blocks there is one there that’s supposed to be for the transmission and then there’s also one at the base which you would use for your distributor that would be considered a port vacuum. Remember manifold vacuum will suck real hard at an engine idle and ported vacuum would be increasing as you accelerate so those vacuum ports are not to be confused. Ported is for your distributor advance and manifold vacuum is for your tranny modulator. Maybe take some pics to show us so maybe one of us can find or see something that would cause a higher idle.
 

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I'd back off the idle setscrews for both carbs until they aren't touching the throttle arms Dave. That may result in the engine not idling at all, but then you can slowly crank in adjustment until the idle is where you want it. If it still idles high with both carbs backed of then something is holding the throttles partway open. Could be in the linkage connecting the two carbs, or could be a gasket hanging up the butterflies in one or both carbs. Try pushing the throttle closed manually and see if you feel it move or feel resistance.
 

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Discussion Starter · #618 ·
Mario, I never cracked the bowls. I was scared and when I took the screws out, the bowl would not budge, so I moved on. I will snap a picture of the sides if the carbs to show where the vacuum plugs are. I know every one of them is either plugged or has a line to it.

Vall, I have everything disconnected throttle wise. Idle screws are all the way out and the throttle cable is off too. I can open and close the throttles while the engine is off so I think the gaskets are OK. They are the square opening. At least I do not feel anything catching on the blades.

On a good note, I got my drag link figured out and ordered from Speedway!
 

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Discussion Starter · #619 ·
also, here is the funny thing. My accelerator pump does not have the vacuum ports on the lid like you guys have.
 

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also, here is the funny thing. My accelerator pump does not have the vacuum ports on the lid like you guys have.
You mean the vacuum secondaries don’t have the vacuum ports. They come in a kit when you buy it to do the modification.
 
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