Stop stumble or flood on carbs. Holley carb double pumpers come with primary and secondary accelerator pump and usually only power valve primary side. The purpose of both is to get right amount of gas/air ratio when accelerating from low throttle to higher throttle. When you first press on the accelerator, you open air flow and immediately create a situation where there are gobs of air and less gas as when the intake manifold pressure goes down, gasoline flow is lower thru the jets. The carb has 2 ways it makes up for lower gas rate so the car doesn’t stumble on acceleration. They are the accelerator pump which shoots raw gas into carb … and after a few seconds as engine speed comes up power valve begins to open so engine doesn’t starve from lean mixture The power valve opens (upon low manifold pressure) and allows raw gas to come out of bowls to give a boost of gasoline to join what comes thru jets. As the manifold pressure comes up, the power valve closes off and engine begins to run on jets alone again. Holly designed the power valves to open when the manifold pressure goes down a certain amount … usually 6.5 inches of vacuum on standard car, or 2.5 to 3.5 inches of vacuum for high performance engines with low manifold vacuum. Where you get in trouble is when running a carb with 6.5 inches of vacuum and you have a high performance cammed engine and the power valve the opens at 2.5 inches of vacuum. Under these circumstances, the power valve is open all the time … causing the engine to flood at anything but full throttle. So the mismatch of correct power valve causes one of two problems. When using a 6.5 inch power valve in a race engine with low manifold vacuum the power valve almost never opens causing engine to stumble when throttle is opened. And when using a 2.5 - 3.5 inch power valve in a stock engine (standard manifold vacuum) the engine always runs rich … really rich … because the power valve never closes. When switching around Holley carbs from car to car this happens a lot … when you change service the power valve needs to be changed so you match engine type to power valve setting. Wrote this when I noticed you guys were having trouble with engine stalling upon acceleration thinking there was something wrong with carb … but I’ll bet you were putting a carb with a 6.5 inch power valve in a car with a big cam … thus almost never opening power valve when you need it. Causing engine stumble. The low manifold vacuum is a result of cam keeping intakes open longer (more overlap) creating the lower maniford vacuum and requiring a power valve of 2.5 - 3.5 inch setting.
Excellent video Ma’am! I like your carb base bolt idea and I never considered inverting my bowls to get my floats close before start-up! Keep up the great work!
It really warms my heart to see a young person that is familiar with a carburetor. Not all hope is lost. But I can’t remember if you said you were told it was a vacuum secondary. That particular carb is not. It’s a double pumper.
I never imagined that I would see such beautiful hands rebuild a 750 Holley. Thanks Liv, my 750 is sitting here in the kitchen waiting to do what you just did.👍🥰
For your and Travis have helped a old man keep going on projects. Bought 3 and I will keep you two posted. 90 K-5, and a 97 T-Bird/ a E-350 for the drive train parts for the car. Great weekend to you both! Can't wait to see how you are doing with the Tempest as it keeps going on.
Very cool Liv. I've never been inside a carb. I've always been intimidated by all the small parts and I know I'd forget something. You made it look easy. Hope you're having a good 2022 so far!!!!👍
Great video Liv. You should do more stuff like this. Cleanest carb rebuild I've ever seen. Every other carb rebuild on TH-cam is either hitting it with a fixit make it happener or on the back of tailgate covered in grease. 😎👍
Hi missed your Videos, if you were gonna run that carb on a motor without a 4hole spacer you should leave the 2 inner base plate screws out most holley carbs come without the, they can fall out and drop into the motor making a BIG MESS. I like the bolts you use for a stand, i use a piece of thick round cardboard tube that fits over the air cleaner base then you can work on it upside down too. Love Watching you race too
Thank you for posting this very informative video! I bought the latest Harbor Freight ultrasonic cleaner & it cleans small carburetors to like new condition, after watching your video I think my Holley will break down into small enough parts to fit inside the cleaner.
based on the the 8 base plate screws, and accel pump check balls this is pretty old carb. 1980's or so. I would suggest getting rid of the two base plate screws that hang over the intake plenum. They have been known to fall out and down the engine. Very bad things happen. Newer Holleys don't have them. You're hurting a lot egos making this look so easy. Keep it up.
You did a good job describing your assembly steps and I like your methods. But you rotated the carburetor counterclockwise with the primary side facing you before inadvertently installing the primary squirter with the squirter nozzles into the secondary side. But I'm sure you were probably just testing us to see if anyone was paying attention. ;-) Keep up the good work, I love seeing your videos.
@@GnarlySpeedShop I knew it wouldn't take you long to notice because you are a pretty smart lady. The only reason I noticed is because I have a Holley 670 - 4150 on my 78 Corvette and never disassembled. That's why I was watching you closely, I don't think anyone would have noticed unless they have one on their engine.
Awesome show do you notice the metering plates they only fit on the front or back a certain way because they are penned the back can sit on the front and the front can't fit on the back cuz they are penned and assign a certain why on the main body of the carburetor also remind them about the power valves if you backfire the carburetor it blows the power valve out and you will have to replace it is short-term what I am trying to say the front and sit on the back and the back can't sit on the front because it has a different pen setting you have a awesome show awesome knowledge thank you God bless oh by the way I forgot Holley carburetors R1 the best carburetors ever built or manufactured
Great video, good detailed information and to top it off, I was very surprised to see such a beautiful woman representing, good stuff thanks for the diy vid
Nice informative video, you did a nice clean job rebuilding the carb. The only thing I noticed was you put the fuel bowls on the wrong ends, they need to be swapped. The fuel line hookups are on the throttle side, they should be on the opposite side of the throttle linkage.
It’s so curious to me to see how the ladies grabs the tools using only her fingers, almost never touches nothing white the palm of her hands… 😊 Saludos!
Hey guys! It’s been a while but there is LOTS of new content coming soon. 😊
GOOD! We've missed you.
Stop stumble or flood on carbs.
Holley carb double pumpers come with primary and secondary accelerator pump and usually only power valve primary side.
The purpose of both is to get right amount of gas/air ratio when accelerating from low throttle to higher throttle.
When you first press on the accelerator, you open air flow and immediately create a situation where there are gobs of air and less gas as when the intake manifold pressure goes down, gasoline flow is lower thru the jets.
The carb has 2 ways it makes up for lower gas rate so the car doesn’t stumble on acceleration. They are the accelerator pump which shoots raw gas into carb … and after a few seconds as engine speed comes up power valve begins to open so engine doesn’t starve from lean mixture
The power valve opens (upon low manifold pressure) and allows raw gas to come out of bowls to give a boost of gasoline to join what comes thru jets.
As the manifold pressure comes up, the power valve closes off and engine begins to run on jets alone again.
Holly designed the power valves to open when the manifold pressure goes down a certain amount … usually 6.5 inches of vacuum on standard car, or 2.5 to 3.5 inches of vacuum for high performance engines with low manifold vacuum.
Where you get in trouble is when running a carb with 6.5 inches of vacuum and you have a high performance cammed engine and the power valve the opens at 2.5 inches of vacuum.
Under these circumstances, the power valve is open all the time … causing the engine to flood at anything but full throttle.
So the mismatch of correct power valve causes one of two problems.
When using a 6.5 inch power valve in a race engine with low manifold vacuum the power valve almost never opens causing engine to stumble when throttle is opened. And when using a 2.5 - 3.5 inch power valve in a stock engine (standard manifold vacuum) the engine always runs rich … really rich … because the power valve never closes.
When switching around Holley carbs from car to car this happens a lot … when you change service the power valve needs to be changed so you match engine type to power valve setting.
Wrote this when I noticed you guys were having trouble with engine stalling upon acceleration thinking there was something wrong with carb … but I’ll bet you were putting a carb with a 6.5 inch power valve in a car with a big cam … thus almost never opening power valve when you need it. Causing engine stumble.
The low manifold vacuum is a result of cam keeping intakes open longer (more overlap) creating the lower maniford vacuum and requiring a power valve of 2.5 - 3.5 inch setting.
Excellent video Ma’am! I like your carb base bolt idea and I never considered inverting my bowls to get my floats close before start-up! Keep up the great work!
It really warms my heart to see a young person that is familiar with a carburetor. Not all hope is lost. But I can’t remember if you said you were told it was a vacuum secondary. That particular carb is not. It’s a double pumper.
I never imagined that I would see such beautiful hands rebuild a 750 Holley. Thanks Liv, my 750 is sitting here in the kitchen waiting to do what you just did.👍🥰
For your and Travis have helped a old man keep going on projects. Bought 3 and I will keep you two posted. 90 K-5, and a 97 T-Bird/ a E-350 for the drive train parts for the car. Great weekend to you both! Can't wait to see how you are doing with the Tempest as it keeps going on.
Your skills really show in this video. Operating a screwdriver the way you do is an acquired skill. Love it! 👍
Thank you Liv for a really complete and informative carb rebuild! You made it look so easy!
Good deal I love the car content junk yard treasure hunts and news on the firebird .
Very cool Liv. I've never been inside a carb. I've always been intimidated by all the small parts and I know I'd forget something. You made it look easy. Hope you're having a good 2022 so far!!!!👍
Great video Liv. You should do more stuff like this. Cleanest carb rebuild I've ever seen. Every other carb rebuild on TH-cam is either hitting it with a fixit make it happener or on the back of tailgate covered in grease. 😎👍
Hey Liv SO happy to see you back.
Thanks Bob! I have LOTS of new videos coming in 2 weeks! 😊
Hi missed your Videos, if you were gonna run that carb on a motor without a 4hole spacer you should leave the 2 inner base plate screws out most holley carbs come without the, they can fall out and drop into the motor making a BIG MESS. I like the bolts you use for a stand, i use a piece of thick round cardboard tube that fits over the air cleaner base then you can work on it upside down too. Love Watching you race too
Congrats on the O’Reillys ad. Been following for a while. Well earned
Thank you for posting this very informative video! I bought the latest Harbor Freight ultrasonic cleaner & it cleans small carburetors to like new condition, after watching your video I think my Holley will break down into small enough parts to fit inside the cleaner.
I’m about to rebuild mine today & got the same rebuild kit. I’ve never done it before, so I’m researching before I wrench!
based on the the 8 base plate screws, and accel pump check balls this is pretty old carb. 1980's or so. I would suggest getting rid of the two base plate screws that hang over the intake plenum. They have been known to fall out and down the engine. Very bad things happen. Newer Holleys don't have them. You're hurting a lot egos making this look so easy. Keep it up.
good to know thanks!
I learned a few things. Thank you. I think it would be cool if you did a carb video that shows a float switch and solenoid conversion.
The little hands come in handy on carb work.
You did a good job describing your assembly steps and I like your methods. But you rotated the carburetor counterclockwise with the primary side facing you before inadvertently installing the primary squirter with the squirter nozzles into the secondary side. But I'm sure you were probably just testing us to see if anyone was paying attention. ;-) Keep up the good work, I love seeing your videos.
Good catch! I caught that mistake too when editing the video but hoped no one would notice 😆 haha fixed it off camera!
@@GnarlySpeedShop I knew it wouldn't take you long to notice because you are a pretty smart lady. The only reason I noticed is because I have a Holley 670 - 4150 on my 78 Corvette and never disassembled. That's why I was watching you closely, I don't think anyone would have noticed unless they have one on their engine.
AWESOME vid....you do a good build up of the Holley....an FYI...you didnt mention on how to adust the accelerator pumps...no biggie....MOPAR 4 EVER.
Awesome show do you notice the metering plates they only fit on the front or back a certain way because they are penned the back can sit on the front and the front can't fit on the back cuz they are penned and assign a certain why on the main body of the carburetor also remind them about the power valves if you backfire the carburetor it blows the power valve out and you will have to replace it is short-term what I am trying to say the front and sit on the back and the back can't sit on the front because it has a different pen setting you have a awesome show awesome knowledge thank you God bless oh by the way I forgot Holley carburetors R1 the best carburetors ever built or manufactured
Great video! How about a video rebuilding a Quadajet. I’ve got to rebuilt the one on my Corvette.😎😎
Some of the comments made me chuckle great video
Thanks! Used this to rebuild my 4160 into a 4150 for blow through supercharger :).
Great video, good detailed information and to top it off, I was very surprised to see such a beautiful woman representing, good stuff thanks for the diy vid
Glad you enjoyed it!
Great video! Keep me coming!
Nice informative video, you did a nice clean job rebuilding the carb. The only thing I noticed was you put the fuel bowls on the wrong ends, they need to be swapped. The fuel line hookups are on the throttle side, they should be on the opposite side of the throttle linkage.
How can you not love this !
Good job. Looking forward to more content.
Groovy! I just followed along with you as I did mine; easy peazy lemon squeezy. Now to see if it worked...
Yep it’s good as new again. 69 Firebird back on the road!
Excellent video! Thanks for sharing
Very informative!
Ii
I like to use vasa,line on the screws and gaskets.
It’s so curious to me to see how the ladies grabs the tools using only her fingers, almost never touches nothing white the palm of her hands… 😊 Saludos!
Hey Great Video Liv!!
Thanks for watching Jason! Wait till you see the new project car I’m picking up in 2 weeks 😉
@@GnarlySpeedShop can't wait Liv
I’m about to rebuild a 4160 600 CFM. Both pretty similar looks like
Great work!!
very well done video. thank you
Awsome
Thats some good info. Thanks.
I. Like a 650 or 700. No down leg bosters.
Straight leg boosters. Not 750. 700 or smaller.
Good job …………..Kev :)
Thanks Kevin!! You rock
Finally a beautiful woman that can rebuild a carb, If you ca cook you would be the perfect woman!!
Nice❤
Can you teach my wife how to do this
Hey are you single by chance lmaoo
Looks like a 850.