[Tom Vaught]

There is a relationship between the size of the ball, the drilled hole in the housing, the clearance around the large ball in the hole, the primary signal hole pick-up point, the secondary signal hole pick-up point, and the vacuum diaphragm spring. They all have to work together. The only tuning on the circuit HISTORICALLY has been by using the vacuum diaphragm spring kit with the different colored springs and their spring rates.

Why would you run with no ball or with a ball size not designed for the stock vacuum housing?

I will have to look at one of the black "quick change cover" plastic housings and see if it uses the small ball. Stock vacuum housing uses the large ball for the calibration to be right.

Tom V.

[lust4speed]

I haven't really questioned the use of the ball before, but looking at the diagrams it appears that the ball/seat has to provide a controlled leak and not a positive seal. Looks like only way for vacuum to pull up the diaphragm is leakage past the check ball? Guess without the ball the movement of the diaphragm would be both too quick and erratic?

[Tom Vaught]

Originally Posted by lust4speed

I haven't really questioned the use of the ball before, but looking at the diagrams it appears that the ball/seat has to provide a controlled leak and not a positive seal. Looks like only way for vacuum to pull up the diaphragm is leakage past the check ball? Guess without the ball the movement of the diaphragm would be both too quick and erratic?

Correct. The ball is not blow-out protection.
It is two things: a controlled leak and a calibrated "mass of the ball' vs the signal (lift) capability of the circuit.
They both work together to have a smooth secondary opening IF you use the right spring rate in the housing vs the engine load.

Tom V.

["QUICK-SILVER"]

Originally Posted by kyle_blake

That's all I'm saying. With the ball there, it plugs the hole, thus you have to wiggle it around until ball moves out of area.

------

Second pic, I dropped the big ball into the slot. I decided to run small ball. I've never ran a ball in there before.

The ball isn't suppose to seat in the hole. If the wrong size ball lets it seat and seal off, the vacuum pot can't bleed back off. I'm thinking most of the seats, in the pot, have a small pick mark to regulate pull and keep the ball from fully seating.

I too have ran Holleys without the ball. Even drilled the hole bigger on models that used a brass restrictor in place of a ball. That's with engines and applications where the engine could stand or needed the faster four barrel opening. Steep rear gears with high stall converters, etc.. Definitealy a not for everybody thing to do. More of a 'mission specific' deal.

Clay

[Tom Vaught]

You have it figured out Quicksilver.

Tom V.

[kyle_blake]

Ok, I will run the larger of the two balls I have. I don't want to stem away from stock. Thanks for detailed answer.

I think I found what could be producing the whistle noise. I can re-produce it by putting carb back on car. Then trying the throttle - just moving it 1%-25% I can hear the squeak noise. Almost like the primary throttle shaft needs lubricating or one of the round bore plates is "slightly off". I remember removing one of them once and putting it back on.

There is no play at all in the shaft, it is not worn.
So I'm figuring when car runs the squeak turns into that brutal whistle.

Thanks everyone for help and explanations.
I'll report my findings back.

[HWYSTR455]

Just to throw it out there, the 'slosh guard' on the plate does just that, but not a very good job of it. The plates allow for upgrade to the 'slosh tubes', or 'whistles', which prevents fuel from sloshing in the vent much better.

Just make sure the bowls you have will support using the baffles, the bowls used with transfer tubes/side hung floats aren't deep enough, as are some others.

https://www.summitracing.com/parts/hly-26-89

.

[74Grandville]

I always install the Large Ball as the secondary blades will open/close to quickly with out it which could cause a bog. almost no HP gain with removing it as far as i'm concerned on the street.

[kyle_blake]

HWYSTR455 - > Hey how are you? Thanks again for those parts! That slosh upgrade link you provided is super useful, this is good to know. I have center hung floats so technically it should work? I've never installed those before, I'll have a look at the metering bodies to see if they support those.

For sure I'm putting the large ball back in, so glad I asked! Now to figure out why the primary shaft is squeaking when dry testing.

[Tom Vaught]

You can typically back off the throttle blades in all 4 positions (with the idle speed screw backed off) and lightly tap each blade to center it properly in the bores of the main body, retighten the screws, then you can reset your idle speed screw back to the same turns as what it was before and fine tune the idle from there.
The squeek should go away. While you have it off squirt a few drops of light oil in each end of the throttle plate base and also between the two blades in that small support area.

Tom V.

[HWYSTR455]

Originally Posted by kyle_blake

HWYSTR455 - > Hey how are you? Thanks again for those parts! That slosh upgrade link you provided is super useful, this is good to know. I have center hung floats so technically it should work? I've never installed those before, I'll have a look at the metering bodies to see if they support those.

For sure I'm putting the large ball back in, so glad I asked! Now to figure out why the primary shaft is squeaking when dry testing.

Yeah man, my pleasure! Those vents are easy to install, and should work for you. They make a diff in braking, launching, and turns. Used to have to feather the throttle at the end of a straight when I let off braked and went into a turn, it's a dance with a manual trans!

.

[kyle_blake]

Hi,

Well I centered round plates and tightened the screws. On the bench not attached to main unit and not on car, no squeak. Put together , put on car, manually activate throttle - squeak. It changed pitch of i put the throttle to one side. Again there is no play up and down but must be a slight tiny 1 thousandth of a inch right to left in shaft. That is what it feels like.. but you'd never really notice. Again if you push lever ever so slightly into the carb as activating the throttle it must be pushing the circle plates into the bore, or the shaft itself is just super dry.

I'm going to do as Tom suggested and apply some oil to the shaft location. I'm assuming some engine oil is fine. Probably wouldn't hurt to actually remove the whole primary shaft, lubricate and install again. I wouldn't call for a bushing kit on it or anything.

I will go back now that i know a bit more about why it's doing it and try lubrication.

Other topic, I took a pic of rear metering block, i don't see where the slosh tubes would attach, it must be too old.

Have a look.

Other topic, I went back to the big ball. Probably unrelated, I've never had this happen before, has anyone ever had a perfectly good looking diaphragm expand incorrectly? As you can see in the pic, crumpled when pulled down. The spring installed. The rod is shorter then the hook up spot, as seen in pic. Probably normal. I should probably install the spring and top part first, then pull rod down to secondary shaft and attach. I didn't do that and it's operation is not right. Not smooth at all, i know it should be.

MY question is do you put assembly in when the diaphragm is in it's relaxed position? I'm going to try that now. I don't think the diaphragm part # is wrong and the rod length is incorrect but who knows. I'm sure learning a lot, thanks again everyone.

[Skip Fix]

"Other topic, I took a pic of rear metering block, i don't see where the slosh tubes would attach, it must be too old. "

The "dimple" on top is where you drill the hole for the little staking pin.[I] want to think the instructions even came with what size to dril when I got some a few years ago. I think Quick fuel has some that pop in place but look a little short to me.
https://www.summitracing.com/parts/qft-59-10-10qft

[Tom Vaught]

Originally Posted by kyle_blake

Hi,

Well I centered round plates and tightened the screws. On the bench not attached to main unit and not on car, no squeak. Put together , put on car, manually activate throttle - squeak. It changed pitch of i put the throttle to one side. Again there is no play up and down but must be a slight tiny 1 thousandth of a inch right to left in shaft. That is what it feels like.. but you'd never really notice. Again if you push lever ever so slightly into the carb as activating the throttle it must be pushing the circle plates into the bore, or the shaft itself is just super dry.

I'm going to do as Tom suggested and apply some oil to the shaft location. I'm assuming some engine oil is fine. Probably wouldn't hurt to actually remove the whole primary shaft, lubricate and install again. I wouldn't call for a bushing kit on it or anything.

I will go back now that i know a bit more about why it's doing it and try lubrication.

Other topic, I took a pic of rear metering block, i don't see where the slosh tubes would attach, it must be too old.

Have a look.

Other topic, I went back to the big ball. Probably unrelated, I've never had this happen before, has anyone ever had a perfectly good looking diaphragm expand incorrectly? As you can see in the pic, crumpled when pulled down. The spring installed. The rod is shorter then the hook up spot, as seen in pic. Probably normal. I should probably install the spring and top part first, then pull rod down to secondary shaft and attach. I didn't do that and it's operation is not right. Not smooth at all, i know it should be.

MY question is do you put assembly in when the diaphragm is in it's relaxed position? I'm going to try that now. I don't think the diaphragm part # is wrong and the rod length is incorrect but who knows. I'm sure learning a lot, thanks again everyone.

1) You have one of the quick change spring housings. you should put the spring you want to run in the housing on the metal part of the diaphragm and add the metal cover before you install it on the throttle shaft lever arm.
2) You do not need to take the plate screws completely out of the shaft to oil the shafts.
In fact you should leave them alone.

Take the carb off the engine
Turn the carb so that you can see the throttle shafts from the bottom
Tilt the carb so that the shafts are vertical.
Throttle lever side down. Squirt oil between the baseplate and the shaft and let it seep past the shaft into the baseplate bores.
Flip the carb so that the throttle lever is up.
Squirt oil between the baseplate and the other end of the shaft and let it seep past the shaft bores.
Do the same thing on the outside of the baseplate where the shafts exit. Same deal, dribble oil into the void between the shaft and the aluminum bores around the shaft.

Removing the blade screws if a dangerous deal if you do not restake them properly. Think throttle blade screw or throttle blade caught in a intake valve.

You are doing great, keep after it.
Tom V.

[kyle_blake]

Hi,

I tried to build the vac diaphragm by holding the rod up with one finger, attach the spring assembly, tighten. It just crumbles and is not a smooth operation from full extension back to top of housing. It's like the rubber has lost it's elasticity. In the pic you can see inside the housing and it has crumble zones.

It would be a very erratic secondary opening and wouldn't even probably fully extend. I think it's best to buy a new one. I suppose the "rubber" o-ring on the top "MAY" not be sealing right but it's highly unlikely.

Thanks Tom, I'll apply some of that 10/30 oil ,as seen in pic. Working it in.

[kyle_blake]

Ignore the comments regarding the diaphragm , the reason it's crumbling is regardless of which ball I choose, when inserted - plugs the orifice. This is why it's unable to pass air properly and is causing this crumbling effect. Essentially I'm pulling rod down and orfice is plugged. I guess i need to locate the right ball system for this carb.

I was hunting down google pictures. I believe this link is what my early model 3310-3 most likely came with.

https://www.google.ca/search?q=vacuu...YkPE7H3C_LpnM:

Have a look.

[Tom Vaught]

The third picture in the group,of pictures shows the stock 3310 housing/ball.diaphragm.

You have to put the diaphragm in correctly so that the hole is above the ball and the ball has room to move upward. The diaphram thickness is enough to allow the ball to unseat because the ball sits below the vacuum diaphragm housing with a stock set-up.

I have several of the quick change kits down stairs, I will look at one of them tomorrow evening and post what my parts show.

Tom V.

Otherwise I could send you a proper stock set of parts.

[kyle_blake]

1 - Oiling the shafts worked, they don't squeak on the car, not running. Much smoother.

Will try running it tomorrow and see if whistle is there.

Carb is back to complete stock jetting. All new gaskets - Shooter is back to 31 stock.

Oh by the way - I never backed out the screws fully on the round plates. Ever. Just 1/2 turn. Even after they were seated. I put a little loc tite red on the other side. Where threads show. Maybe it holds maybe it doesn't. Forgot if seals in absence of air or not. Then it would need the be on the actual threads as designed.

Have a good night, thanks again.

[HWYSTR455]

Originally Posted by Skip Fix

"Other topic, I took a pic of rear metering block, i don't see where the slosh tubes would attach, it must be too old. "

The "dimple" on top is where you drill the hole for the little staking pin.[I] want to think the instructions even came with what size to dril when I got some a few years ago. I think Quick fuel has some that pop in place but look a little short to me.
https://www.summitracing.com/parts/qft-59-10-10qft

Was going to mention the dimple but forgot. And yeah, there's a really small folded up piece of paper that comes with the vents that are the instructions, and it does state what drill to use, which I'm fairly sure is a numbered bit.

Those quick fuel ones look interesting, but yeah, they do look a little shorter. Anything is better tho. Curious how those stay in if they're not staked? And wow, that price is for 10 of them.

.

[kyle_blake]

Hwy-> I found the instructions online for the tube's you mentioned. Makes sense to drill then use those screws found to bind right into the casting.

Tom - > One more call to tech support, lol the dreaded tech support, he told me they currently don't ship new carbs with a ball in them. They use the that brass fitting. He seemed to think it's fine to run without it. He said worse case scenario it would open sooner and you would just go to a stiffer spring. When I use either ball, it plugs the hole and well essentially no secondaries at all. I'll get around to firing up the car and report back on this whistle when things settle down and I'm not as busy.

Thanks again everyone.