Thank you.

You are very welcome.

Thanks

I'm glad I could help.

Glad I can help.

You are very welcome

Thank you.

Good luck.

I'm glad I could help, have a great Christmas.

Thanks Senia. l'm glad the video helped , hope to do the 850 throttle plate to the 750 main body soon, thanks for watching.

Thank you for watching.

Randy. Thanks for the kind words I should have some more Holley mods soon.

You know I rebuilt thousands of carburetors , before ever making improvements and modifications to the fuel curve , I guess a lot of it comes from my love of racing. Thanks and good luck.

You are very welcome.

Glad I could help.

Thank you.

Glad I could help

Thanks Justin I appreciate it.

Glad to here that.

You are most welcome.

Thanks for watching

Thanks , will have some new videos soon.

Doug glad I could help, thanks for watching.

Thank you for watching.

We will be making a pump cam video soon on the Holley carburetor . check your accelerator pump check valve its underneath your discharge nozzles and lot of times that little check valve sticks, remove the Phillips head screw that holds the discharge nozzles ,and then take a fine pick and just move the little check valve around just a little and don't move your throttle when you're doing this , because the check valve will come right out and down into your motor and just wiggle it around a little with that pic and then put it all back together , if this is the problem it usually takes care of it. If it's always had a stumble refer back to my last video, hope this helps if not let me know.

Thanks will do , this is an extreme street strip turbo big block with huge power that typically has very good street manners .

Man I have a 71 nova big block my self, there's no substitute for cubic Inches.

Holley Carbs: How To's & Advice ,40 yrs of exp. you’re right there 555 cubes for me

You may have to go to a 50cc pump , and 50cc pump cover and arm and use the brown pump cam , then keep increasing your pump nozzles until the hesitation goes away .hope this helps.

Thanks for watching Doug.

Thank you.

Thanks for watching

You are very welcome

Thank you, and if I can help you please let me know.

You are very welcome.

Your welcome.

Thank you.

How did it go?

@@MHM4V3R1CK it went perfectly, all the settings were out so I just followed the videos and it ran the best it had in my 4 years of ownership , just in time to sell it !!!!! Wish I'd found d this channel along time ago. Cheers.

Good luck .

Thanks I appreciate it.

It is important to know the check valve and counter weight is working properly. Make sure its a very light tap with a small hammer. Thanks for watching.

@@holleycarbshowtosadvice40y90 Yes, recently had problem with sticking check valve in 650 DP, delaying pump shot. Good tip. Thanks.

Your welcome.

Thank you

Thanks

Thanks Bruce

Wayne thanks for watching.

Thanks

Thanks for warching.

Thank you

Good job.

Thanks Bill.

Thanks

It's very unusual to have a power valve cause a stumble right off idle and it's a lot easier and cheaper to change accel. pump adjustment or discharge nozzle size than to open up the carburetor .

Thank You

Thanks Tom.

Thanks

Good luck Alex , thanks for watching.

Your welcome.

How high does the engine temp get and this only happens when your idling with temp rising, I don't think this is going to be an accel pump issue , let me know when it stumbles does it cut off or does it back fire through the carb or exhaust , what helps to get through the stumble , need all the information you can give me.

@@holleycarbshowtosadvice40y90 Thanks for replying!! The temp if i get caught at a full rotation at a traffic light, gets up to around 200 ish and if i take off at a normal speed, it stumbles about 3 times and acts as if the motor shut off but i just let off the gas and it never quite kills the motor.A few years ago, it killed the motor but it re-fired. No backfires of any kind. I have the accelorator pump set just as the throttle is being applied and have a discharge at the exact time I also have .015 left over for the pump arm during wide open throttle. I'm running dual electric fans that come on around 130 degrees.

Chad shoot me some pics of the fuel system, carb , spacer and the fuel pump and fuel lines under the hood or electric pump and where the fuel pump is mounted verses the fuel tank also pics of distributor and if your running a ballist resistor and are you using original ignition wire feeding distributor and what kind of distributor and I will give you a list of things to check. My Email is Racingbigblockchevyman1121@gmail.com. I'll try my best to help you.

Thanks and if I can help let me know.. have a good one.

@@holleycarbshowtosadvice40y90 u also sir appreciate you

Thank you .

Thanks David.

@@holleycarbshowtosadvice40y90 I could use some advice. I built a 468, 454 at .60 over. 10:1 compression with AFR heads. I think I under carbed it with a 750 vac But lol after breaking in the cam I'm 13 minutes I sucked down almost 5 gal gas. I think my power valve is off. I'm running the big mother thumper cam. Any suggestions.

@@holleycarbshowtosadvice40y90 also I rebuilt the carb. I blew out the air bleeds one was stuck. I like your advice on the 50 cc and mods for a squirter

I don't understand your terminology I need more information ., And rolling down hill with your foot off the gas hesitating?

If you have a air gap dual plane intake, try jetting up at least two sizes on primaries and secondaries see if that helps performance.also keep reading your spark plugs .I Make a 1/8 mile pass then I kill the engine , coast to my pit , pull the plugs and read how they are burning.

Charles just google pin gauges .011 to .060 thousandths. Hope this helps.

Gas coming out of your vent tubes could mean several things , fuel pressure is high, should be 6psi or less if its high correct that first , also bad or sticking needle and seat , bad float , or bad sealing surface around the needle and seat o ring or the o ring itself , anything restricting the vent can cause it, hope this helps . On your second question I need to know if your carburetor has a choke.

Your welcome.

Thats Great.

Thank you for watching

Send me your list # off the front of your air horn.

Holley Carbs: How To's & Advice ,40 yrs of exp. sure will do I will drive up next weekend and take a look it’s in storage at the lake Thanks 😊

You need to check everything they did, 50cc conversion consist of 50cc pump housing, diaphragm , and a taller spring, also the accel pump arm is different and pump cam, most of the 50 cc pump cams are brown, probably has wrong pump arm , but check all of it to make sure they did the install correct. Hope this helps.

@@holleycarbshowtosadvice40y90 pump cam looks to be more of a light tan color then brown. Could be faded though. Time to do a rebuild Thank you

You are very welcome.

That could be many things could be fuel curve or fuel delivery problems or ignition, could be primary or secondary ignition, ignition box ect , so many components, I know this might not help , but usually fuel, ignition or timing or bad connections.

Woody I believe I would send it back to holley , when you see two mixture screws all the way turned in, that's a red flag. If you won't to fix it your self it needs adjustability, changeable air bleeds idle fuel restrictions pv restriction ect. Also need to know the color the plugs are burning, type of distributor mechanical or vacuum advance and mechanical. And if vacuum advance is used is it hooked to manifold vacuum or ported vacuum at carb , there is so much information needed, you decide and I'll help you any way I can , if it has know adjustability I would definitely seed it back to holley. Hope this helps.

Thanks.

Where I usually get mine is off the snap on truck or matco tool truck , I'm sure any quality tool company would have them., I ask for carburetor drill bits and they usually will sell you the little hand held pin vise to go with the drill bits..

Check your gasket between the main body and throttle plate, the wrong gasket can block the idle circuit and cause it not to idle.

Most carburetors just need a rebuild kit. They are calibrated for the specific car there made for. I'm not sure what you mean by starts having its own mind.. if you can explain more clearly mabe i can help.

With the engine off, look down the carburetor throat and as you move the throttle make sure the pump is squirting the moment you open the throttle. If it has any delay at all check accelerator pump arm for any clearance between the arm and pump if so adjust the pump arm so it has no clearance at closed throttle, the only other thing that can cause a delay in the pump squirting are the two check valves in the pump circuit. Always check your timing first before you tune the carb. Hope this helps.

​@@holleycarbshowtosadvice40y90 Hey man, I'm trying to adjust my timing, pretty sure I need to advance it a couple degrees, but the distributor feels like it's dang near welded to the intake. I took the hold down bracket completely off, soaked the base with Kroil every day for a week straight, still no dice. Should I try heat?

Sounds like a good combination , maybe a little tuning , I put a 2 barrel motorcraft carb on my son's 258cu.in. straight 6 in his Jeep , I think all I changed was to a leaner set of jets not sure on the cfm size , . You may not have to change anything, let me know if I can help. Thanks for watching.

Is it a two circuit or three circuit and what size cfm, might be best to call pro systems and talk to them, you can come up with a hundred different fuel curves.

It's possible you could need more squirted, alot has to do with the cam and ignition timing ,the more cam , the more squirted, usually .033 is enough , look at your ignition timing too not enough timing or not coming in quick enough , so many things can cause this ,some times not enough converter , even a weak ignition coil can cause this ,if I new what you had in your engine , compression , cam specs , cu in timing , intake manifold that would help me , make sure zero clearance in acc pump arm , send me so more information and we will do our best .

It helps to control the idle with big cams with lots of duration, I believe it's easier to stage your car . Now because of extra air flow at idle, some times you can tune out a lean part throttle issue ,but when your at wot not much difference. There are more advantages.

The accelerator pump should always squirt unless the check counter weight is not seating , now .026 is not enough usually i run .035.. then make sure you have your transfer slots around .035 . That.should take care of your problem.

@@holleycarbshowtosadvice40y90 Ok thanks, but the ifr was 0.033", too rich at 3000 cruise. I got the cruise afr pretty good now with 28 ifr, and jetting down from 74 to 66. With doing that, Wot is a touch lean at 13.5 afr (primary only), so I will drill the pvcr from 059, to 064". The nozzle is 35, maybe try the 37, see what happens. The pump does squirt its all good, but the throttle is pushed so lightly, it might not be enough. If I stab it quicker, it's good..

Jake before you drill your pvcr start by changing your ifr circuit back to .033 to .035 then correct your 3000 cruise with a main jet change and your wot may be ok get your air fuel correct then check your 1300 to to 1800 cruise and check ifr fuel ratio.hope this helps.

I dont know if they make any kind of repair kit.

You can helicoil it but will need to use hollow screw. The screw size is 12-28 if you can find helicoil kit that size.

Is your accelerator pump discharge nozzles clean and working , next check and see what size the discharge nozzles are , usually an off idle stumble is due to not enough accelerator pump shot, may have to go at lest four sizes bigger. Hope this helps.

@@holleycarbshowtosadvice40y90 its a brand new Quick fuel 670 Brawler. The hesitation is with very light throttle, like driving through a parking lot slowly, just one little spot, it spikes lean and will stay there if i keep that same throttle position.. 31 squirters in it, orange cam.

Alright make sure there is no play in accel. Pump arm and try a .035 nozzle, if that don't work , try a bigger idle fuel restrictor and make sure your float level is adj. properly ,you can also try a smaller idle air bleed both will richen up low speed , as long as this problem is happening before the booster starts flowing. hope this helps. ps make sure your ignition timing is working properly and advancing off idle.

@@holleycarbshowtosadvice40y90 hey thanks for the response! Ill check all you posted.

My opinion- white #218 pump cam THE BEST driving cam.

What kind of distributor are you using, is it all mechanical or have a vacuum advance , and if so where is your hose hooked to on the carb for the vacuum advance. Which carb are you using now, if it's a 1850 let me know does your secondary diaphram housing use a ball check or a small .045 hole for the vacuum to work the diaphram.

@@holleycarbshowtosadvice40y90 I am using the 670 street avenger right now, im not sure if it has a ball or the small hole. The distributor has vacuum advance also. I would like to go back to the 1850. It has the small hole, I do know that.

Ok make sure your distributor vacuum hose is hooked to the metering block which is ported vacuum on most carbs or could be in a different place its according to the carb, you don't won't manifold vacuum. Also if you won't to slow down the secondaries opening use the ball Check housing its ok to switch housing if you have to , alot of people leave the ball out and it will open secondaries early.hope this helps.

@@holleycarbshowtosadvice40y90 yeah, thanks that helps.its nice knowing which one was the best direction to go. We'll see if it fixes it. Do you have any guesses on if the 670 has the the small hole or not?

I would try to use the sec. diaphram housing with the ball check .

What kind of tri power setup do you have, are the front and rear carburetor vacuum operated , they usually are , it runs primarily off the center carb and the front and rear carbs come in at higher speeds If you have a distributor with a vacuum advance ,you will wont to run your vacuum hose from the distributor to the center holley 2 barrel on the passenger side metering block.hope this helps , if you need more help let me know.

@@holleycarbshowtosadvice40y90 Thanks for the follow-up. I can't tell you much about the power setup, for I bought the car used (translate auction), but it is a '69 Plymouth Roadrunner with a 383 and a Pertronix coil/distributor, which has a vacuum advance. The vacuum connections that I am interested in are the ones from the larger ports on the passenger side of the center carb (one near the top and the one near the bottom). I'm thinking they are to attach to a breather valve (driver side) and/or a PCV valve (passenger side), but which goes to what? The current setup is that the breather valve connects to my air filter (driver side); the lower port from the center carb attaches to the PCV valve; and the shop bored a hole into bottom of the air filter (passenger side) and installed a port and connected a vacuum line from it to the upper port of the center carb (I don't think they should have done that). It's a bit wordy, but hopefully not confusing. 🤔

@@dogdoc1 I think the "mystery" hose connection that you mention near the end of your comment is probably a float bowl vent plumbed into the air cleaner which is perfectly fine and a good idea.

@@mickangio16 Thanks for your reply, because a garage made a connection from my air cleaner to one of those carburetor ports. Good to know.

The vent probably went to a charcoal canister originally. It could have been left open to unfiltered atmosphere where dust and dirt can make it's way into the bowl but plumbing it to filtered air is a better idea.

That's a good possibility , to much pump clearence or blockage at discharge nozzles primary's or secondaries, or needs bigger discharge nozzles, there is so many things to look at , process of elimination don't forget timing and advance, thanks for watching.

If everything checks out ok , either drill your accelerator pump nozzles about .005 larger or change pump nozzles to .005 bigger , this is where having a set of guage pin to size the hole is great to have, the number on the discharge nozzles #25 means its .025 thousandths , note if it's never been drilled before.

Thanks.

Jacksonville fl. Thanks.

Your quite welcome.

You bet,take care.

Thanks.

The check ball slows down the opening of the diaphragm, some holleys use a fixed orifice instead of the check ball, then fine tune with your diaphragm springs.

@@holleycarbshowtosadvice40y90 Iv always taken the check ball out, thought they run ok. Is it still better to use them. Do you use them on your carbs Randy.

Sometimes I use the ball checks but mostly use the fixed orifice, and tune from there. Study the vacuum feed passages for the diaphragm. Hope this helps.

Should be stamped right on the front of the choke housing.

Yes get the list# off the front of the choke housing , then cross list# number to get cfm size , for instance if list# is 3310-2 its a 750 vacuum secondaries the 2 means second generation.

Not usually , most of the time it will be in the accelerator pump , either pump not squirting or out of ajustment, or not enough pump shot. this is the most common problems.

@@holleycarbshowtosadvice40y90 How can you tell if it's too much fuel getting pumped in there or not enough?!

Absolutely

Yes I need to do a video on pump cams.

Holley owns quick fuel , still a Holley carb.

@@holleycarbshowtosadvice40y90 The design of the slayer is totally different than the holly 600 I had on the motor.Maybe holly bought them out because they knew it was better than there's.The slayer is easy to adjust with more fine tuning capabilities than the old holly 600.All I'm saying is my motor runs a whole bunch better than before.

I have one called dialing in your msd distributor. If you have a specific question let me know. Hope this helps

My accelator discharge nozzel had to of went into intake

I don't understand your question please leave me as much detailed information as possible, thanks

@@holleycarbshowtosadvice40y90 Its all good it doesnt have a nozzle on back two barrels

There is alot to air bleeds and I will do a video later, but if you make your air bleed bigger it will lean the mixture, and a smaller air bleed will richen the mixture, there is so much more you need to know, will have to cover the rest in a video. Hope this helps.

@@holleycarbshowtosadvice40y90 - Does a bigger air jet lean it more on the top end and less on the bottom of rpm. Look forward to your video. 😎

You should already have your timing set right to specks, I'm showing you the problems with the carburetor that can cause hesitation. ps timing can cause hesitations. Hope this helps.

Its special lol