O-Ring Hell - A Quick And Easy Guide To Sealing Up The Most Common Holley Fuel Leaks

The new season is upon us, and as cars are brought out of winter hibernation, there are thousands of guys all around the world that are going to have to deal with problems that didn't exist when they put their rides up for storage.
Holley carbs are notorious for developing random fuel leaks after they have been sitting for any amount of time. Here are all the common failure points and how the simple fixes that will get you back on the road with a minimum of cash and hassle.
#classiccar #revival #engines #musclecar #vintagecars #gasoline
MERCHANDISE:
Get Your UTG T-Shirts Here: uncletonysgarage.com/product/...
Get Your UTG Stickers Here: uncletonysgarage.com/product/...
OUR STORE: uncletonysgarage.com
*SOCIAL MEDIA:
Facebook: / uncletonysgarage1

[@captainjohnh9405]

The quality of rubber is indeed lower today. That is why I am a new father!

[@gibbsey9579]

Congratulations.....😂

[@MrTheHillfolk]

Don't ever use those silly bypass caps in the help section of the parts store to cap a hose fitting. Use a bolt ,piece of hose and a clamp. Sure they look better ,but give em 6mo and they crumble in your hand. Damn things piss me off as a gen tech because psi engines come with em from the factory. Replace em at startup ,or in 6mo when it blows and sprays coolant all over.

[@Redneckairflow]

U sir when the internet today

[@MoparMan-ff8fb]

lol 😎👍

[@Hipsters_N_Hippies]

At least you had an excuse.... my first time I got my first kid. Then I hooked up with a girl who doctors figured couldn’t have children.... and after the first two kids in our first three years together, she decided to go get fixed. 💪🏻

[@GaryH-pw9cm]

Back in 1975 I had a Holley 600 on a 65 Mustang. it was not unusual to be driving along and suddenly smell gasoline, pull over, open the hood to find the crossover pipe O rings leaking. But I always had a box of Holley gaskets and parts in the trunk so remove the float bowl and replace the O rings and continue on. Oh, the joys of owning a Holley. 😊

[@briang4470]

If you have a Holley carb on anything, a car,truck,boat,etc.. it's always a really good idea to look at the carb from time to time and constantly check for leaks and check for any deteriorating o rings, accelerator pumps or fuel line, it's best to catch the leak before it happens so you don't burn your ride down, holleys always seem to have a bad habbit of springing massive leaks at the worst possible times. That's why for most daily driver, low performance vehicles, I always opt for a rochester or afb style carb Soo much more reliable and less likely to start leaking. I have seen quadrajets that were over 40+ years old that have never been apart that have zero leaks, can't say the same for a Holley they always leak.

[@weseethetruth158]

Yeah I think I'd just stay away from Holley and Edlebrock.🤷‍♂️💯

[@stevoschannel4127]

Trying to think of any orings on a front and rear feed?

[@lordphullautosear]

Quadrajets often develop leaks at the fuel line fitting. Never had issues with Carter/Edelbrock AFBs.

[@allhailinternalcombustion]

@@weseethetruth158 So what do you run?

[@steveib724]

Yo got me putting my extinguisher back in my ride 3 maybe 4 pounds hmmm 👍

[@JFSmith-nb8hf]

You hit the nail right on the head. If you want peak performance, run a Holly, if you don't want to be constantly messing with it, run a Carter / Edelbrock. I've had Carters that sat for five or six years and fired and run like a champ.

[@DuckyHunter812]

A tech tip from one of the magazines back in the day, for standard holley gaskets if you coat them with cherry chapstick they don't stick.

[@wlogue]

A carb video every couple days wouldn't hurt my feelings. Thanks U.T.

[@bruceabbott3941]

Back in the day, I was a member of our local volunteer fire department, which was equipped with hand-me-down Ford C-cab fire trucks with gas V-8s. The Holley carbs on those engines gave us fits, since the trucks sat so much. Even worse, our old firehouse was so small that we could not raise the cabs to access the engine inside the house. Don't miss those days! Rochester Quadrajets get a lot of grief, but I would store boats with them on 305 and 350 GM engines for 6 months at a time, and they would fire up and run fine. Thanks for the video, Uncle Tony!

[@glocke380]

I always use a silicone based lube when installing the o-rings and it seems to help.

[@felixlafuente9714]

Try using those silocon green orings. They work great!

[@benjaminwatson7868]

Do they work with ethanol gas

[@honda350racer6]

I let my brother-in-law use my old chevelle for a few months it got really hard to start , all it was is the gasoline was draining from the accelerater pump on bottom of the front float bowl.,Holley carbs work very good for people who take the effort of learning about them.

[@bradygregor9137]

Had the same thing happen to me

[@honda350racer6]

@@bradygregor9137 that's some work project you did on the old Ford truck.,I thought about doing something with my 79 fiat 124 ,2 litre motor ,something like a 4 barrel carb but I have to have a totally reliable car no matter what ,

[@gcaprice406]

I learned that Teflon tape lesson the hard way. As a young lad, I Teflon taped the shit out of some fuel lines, and some of the tape worked its way into the carburetor, and got stuck in the needle and seat. Had to nurse the car back home and was driving myself crazy figuring out the problem, but then I showed it to my father, who, of course could tell what was going on right away.

[@matthewsmith6486]

I've been messing with Holley carbs for 40 plus years too! I used to have boxes of them under the bench. People would get fed up with them and just give them to me! Personally I love Holley carbs. Anyway you're spot on. The first start up of the year I always leave the hood up for awhile and check to see if there are any leaks. If there are leaks I fix them and that is usually the end of the problems for a couple of years. Great video.

[@JacksoNR26]

So your saying that the o rings and gaskets last for 2 years

[@matthewsmith6486]

No, I'm saying it's smart to check for fuel leaks when starting a car up for the first time after it's been sitting awhile. Check your brakes before you pull out of the garage too! @@JacksoNR26

[@charlesvanenwyck7317]

I am not complaining about the carburetor videos! : ) There is extremely limited information about carburetors. I will gladly take all I can possibly get. Thank you. : )

[@MoparMan-ff8fb]

Tony - didnt know if you already knew this ? but you can buy an assorted clear box of green O rings used for AC in vehicles from harbor frieght along with a box assorted black rubber O rings . the Orings come in sizes small enough to fit the holly parts . they will with stand gases and other chemicals and temps

[@vtwin6]

I love the carb videos, keep em coming!

[@brianbrigg57]

I've never used a Holley carb with the transfer tube but I think that if I had problems with leaks there I would look at drilling and tapping each side for a hose barb fitting then running some high quality fuel line between them. Problem solved.

[@ssnerd583]

.....and excellent idea....and would be a simple and direct fix

[@GaryH-pw9cm]

I gobbed JB weld on the transfer pipe and it seemed to fix the problem . But it did not look all that great and had to be chiseled off to replace the bowl gaskets. 😊

[@JoesMoparMess]

Thank you UTG, just got my car back from a classic car shop and they couldn’t use my Holley 850 because it was leaking gas everywhere and they recommended I buy a new one. Luckily I had a new in the box edelbrock they were willing to throw on the car. I took back the Holley and was going to do a full rebuild but now I will just start with new o rings.

[@ohm1945]

Always had Holleys, most of which are as Tony said, the 600cfm vac secondary square bore (4160 if I recall correctly). Only months ago, got hold of a used 625cfm Street Demon. Sure, more fine tuning with metering rods, vacuum springs and the like , but no leaks due it’s bowl design. Better for a cruiser or mild street car I’m told but I think the large secondary barrel is ideal for WOT launches. Barry Grant got it right on that front.

[@godsowndrunk1118]

I've torn new transfer tube o-rings when replacing them, so I always lube them before inserting the tube into the back float bowl.

[@michaelfolchetti4624]

What do you lube them with?

[@scotthatch4548]

One thing you missed talking about is that some Holley carbs use a rubber bushing of a sort on the transfer tube as opposed to o-rings and that when putting on the transfer tube to spray the oring with silicone spray so it slides in and does not roll

[@nicksnarski5973]

Right, one other thing I've seen is the accelerator pump diaphragms harden after sitting for a few years.

[@GaryH-pw9cm]

Yep that is for sure. Crunchy.

[@ericwilson2585]

That's so great to know Tony, I'm glad you told me this.

[@outlawbillionairez9780]

Common o-ring material is buna-n rubber. Get viton o-rings instead. More temp and chemical resistant, tougher too. I'll bet you never replace them.

[@ssnerd583]

yeah...the buna-n are not the best, for sure.....viton is the ticket over buna-n

[@tjt4036]

Another great carb. video. Keep them coming UTG.👍👍

[@Carstuff111]

I honestly do mean this, every time I watch this channel, it makes me consider more and more going with carburetors on my Honda. I know people are going to laugh at that, but a 1989 Honda CR-X that was B18 swapped (1.8 Liter DOHC 4 cylinder) running a ported VTEC head, 13.5:1 compression, TODA VTEC killer cams (insanely aggressive cams), and SS Works' own carburetors made 230 horsepower and set a lap record in the early 2000s around Tsukuba Racing Circuit of 59.1 seconds. Honda engines love individual throttle body setups and individual carb setups.....and if I really wanted to go for an all out build, carbs would ironically be easier to deal with than individual throttle body tuning.

[@ClaremontClassicGarage]

Don't forget the well seals on TQs !

[@TheCanadianBubba]

Sponging up all the Holley info... Thanks Uncle Tony 👍

[@renaissanceman4054]

I've had those miserable things leak everywhere. Around the bottom bolts holding on the bowl, transfer tube, around the needle/seat. I got tired of messing with them and got edelbrock/carters instead, they've been perfect

[@roflman]

The leaky transfer tube got me for a while, because by the time you shut the car off and lean over to have a look, the fuel has dribbled down around the pump diaphram and you think you've got a bad pump shot. (btw the teflon tape does work well temporarily on the transfer tubes if you don't have an oring handy, seals well for a few weeks before the gas melts it)

[@sewing1243]

If anyone is tempted to use a teflon tape then at least buy the fuel rated version: yellow PTFE tape The plain white teflon PTFE tape is best used for water and it does not have resistance to chemical compounds (like gasoline). The yellow PTFE tape will work for household plumbing (but a roll of the yellow costs twice as much as the white tape).

[@themissingkeyexplainsevery7671]

GREATE VIDEO,,,,ALL INFORMATION IS GOOD INFORMATION .GREAT JOB.....I LIKE WHEN PEOPLE ACTUALLY KNOW WHAT THEY ARE TALKING ABOUT

[@P.R.Shriram]

I've been chasing mysterious overfueling and hadn't thought to check the needle & seat, thanks uncle tony!

[@broke_dongle]

Float check always , I washed rings from too much fuel.

[@aarongomez5812]

Keep making these videos!!🎉

[@bobbyz1964]

Had Holley four barrels on a couple of old medium duty trucks until the early 2,000s. Those trucks sat more than they ran, all winter, six months up here. Even after Minnesota went to ethanol in the 90s I really didn't have trouble with them leaking. Sure occasionally I'd replace an O ring but it wasn't like an every spring ritual. I'd say it's definitely the O rings today, no idea if there's still US Made ones available today. You can bet the ones at Autozone or whatever aren't made in the States.

[@thomasharvanek2411]

Great stuff as always UT Additionally, one needs to seat the xfer orings with a little spin, pushing each way, and finally centering the tube between the bowls, verses mash together and hope. A little Silicon grease too

[@mrkultra1655]

Thanks Tony

[@olliehopnoodle4628]

I have three 2300's sitting on my 351C. It will usually last a winter or two before it starts to leak. I just replace the needle assemblies instead of trying to put in a new gasket (didn't realize that was a option). Also, check the power valve. The rubber on it can deteriorate too if it gets dry too many times! Great video as always.

[@connorking7785]

Right on

[@ytwatcher8288]

I eat a low-carb food diet, but I love a high-carb info binge...

[@shoominati23]

The next new carb I buy I am going to get the E85 Version. They are sneaking more an more ethanol in fuel that isn't even supposed to have ethanol content, so I am going to spend the money and get the version with the proper parts and seals so I dont end up having a leaking or gummed up carb down the road

[@GaryH-pw9cm]

I remember back in the 80s when they changed the fuel to the new blend. I was going through fuel pumps like crazy. The diaphragms would turn to mush. I took a while before manufactures came up with rubber diaphragms that would not fall apart and leave you stranded.

[@xavierschneider6274]

Thank you for your videos tony.. my father passed away a year ago and left me his 1980 elcamino to continue his build as my first car..(im 18 years of age)you’ve taught me a lot so far thank you.. do you have any story’s of working on any elcaminos or similar builds?

[@thedobermangang3503]

I sure wish I lived next door to this guy..good mechanic..

[@ericdeven1296]

Great tech! I had to laugh yesterday, l bought a 63 mercury meteor and it came with a set of red steelies in the trunk, and when l looked at them they had 3 nubs to hold The dog dished on. I thought about your video that you hoped nobody got anything from, and l new l had mopar wheels. I did, l did get something from it!! Great tech vid.

[@donaldhalls2189]

Even with fuel injection the paper gaskets,and 'O' ring's on the injectors, etc, but a can of starter fluid useualy finds them, the Australian Ford 4 litre inlet manifold has a habit of leaking more from underneath, thanks for sharing, all the best to yous and your loved ones

[@tkracing5875]

The blue re-usable gaskets still stick and rip. At least one did for me on an edelbrock carb. Was together for a few months and only ran carb for a week . Pulled it apart and it stuck and ripped

[@michaelcook7090]

Some close-ups would'a been nice.

[@3rdpig]

When I was a young man I put those Holley 600's on every small block V8 I had that had stock or mild cams. They were half the cost of the 780 and a third the cost of the double pumper 750 and often my local speed shop had them on sale for $50-$70. I had more than one come fresh out of the box with that transfer tube leaking. I think if I were doing it today and wanted to buy new I'd get the Edelbrock 600, or maybe the Brawler 600 with the mechanical secondaries, it has no transfer tube.

[@robertrio1164]

Fumny I rebuilt my 25 yr old 750 double pumper for first time last year. Can't say I had any leaks besides fuel bowl which were fixed by tightening the screws. Granted my GTO only gets driven 500 or so miles a year but it sits most the winter without running. Always found it very reliable and prefer Holleys to the Qjet for ease of starting. I don't even use the choke and it fires up easily. I also have a 750 vac secondary which has been sitting for years. I bet that would leak like a sieve though, so I need to rebuild it for a back up.

[@mikemcgannvoiceover]

I usually buy a full rebuild kit even if I just need one seal. The full kit comes out cheaper when you have to come back for just odds and ends and I'll have extras for next time. So now I have a tackle box of carb goods. It saved me a few times with surprise leaks.

[@lau12342]

I prefer Carter over Holley and this is why. Holleys do make more power when they don't set your car on fire 😀🔥

[@rorydottin7143]

I use Air Conditioning Green Seals for the check valve and cut the the float level adjustment gaskets from plastic oil containers.. works for years..

[@timokuusela5794]

Even "the good old rubber" goes bad with modern gas. The alcohol (and the additives that keep it with gas for few months) make the rubber swell and harden. When there is no gas they shrink back, but as they are now hard, they do not seal any more. I talked to a guy that has sold carb rebuild kits for 30 years, and he told that with the old leaded gas carbs lasted easily 30-40 years without problems, now about 3-5. Happy guy, as his business got boost...

[@robertwest3093]

Those blue reusable gaskets for the Holley bowl and metering block are one of the best upgrades you can do with a Holley. In fact Holley should be ashamed for not selling every new carburetor with the blue gaskets installed. They would have less returns.

[@GaryH-pw9cm]

Yes but when the first come out in the 80s they had some sort of glue that would bond the metering blocks and float bowl together. Taking one of these carburetors apart was a chore without wrecking the carburetor. Holley finally stopped doing this as people started to complain about it.

[@flinch622]

Had my share of o-ring failures, and that crossover tube... its alarming when it goes.

[@23Roadster1]

Tony, if you have access to "bulk" O rings (Amazon; only the black Buna, dirt cheap), the # 009 ( universal numbering system ) fits the Holley transfer tubes and the seats. Also, even with the blue non stick gaskets, they peel a lot easier with a light spray of silicone or WD at each install.

[@rescuedandrestoredgarage]

Carter for the win 🏆.

[@cobyburrow9339]

Also Tony did you mention that you can go to low with needles and seats and cause flooding too? Pass the o ring sealing surface. And sometimes the o ring will get a thread line cut into the o ring causing flooding

[@jimmyraythomason1]

I had a new out of the box Holley 600cfm (3310) leaking at those equalizer tube o rings. I discovered it on the road first trip out. I had to wait for the nearest NAPA to open where I bought 2 o'rings for a total cost of 80 cents.

[@olddonn]

Biggest leak issue I've had with my old Holley 4160 is with the non-adjustable needle & seat plugs on top of the bowls. The plugs will leak, not a question of if, but when. A little JB Weld or Seal-All will stop the leak, but at some point, the bowls will have to be replaced since replacement plugs aren't available. Did that job over the winter.

[@GaryH-pw9cm]

After fighting with Holley carburetors since 1967, I have switched to Edelebrock carburetors. Now I fight with Edelbrock carburetors. 😊

[@raybrensike42]

There was an 0-ring place I used to go to for any kind of 0-ring. They would give me the brown ones which were for ethanol.

[@TheThirdWheel618]

My first 4 bbl Holley was a 600 Vacuum secondary bought as a new in the box from a guy on offer up . The guy tried to tell me it was a 650 but i knew it was a 600 . I did not look at it very good and they had changed the squirter to a 28 and the rear float had a old needle and seat that got stuck down and tuning it was a booger since it was lean there and I jetted it up really high till I figured out what it was . Only good thing was it has the new style transfer tube seals the cup style liking those although I will never buy another used one again without looking really good .

[@gunsbeersmemes]

Last time I was this early to an Uncle Tony video, gas was under $2 lol

[@YODAMAN5]

AWESOME vid UT. Your right, TT useage is a no no there. MOPAR 4 EVER.

[@user-rr8db3mu6y]

once again Tony you are good.Thanks so much.

[@raginroadrunner]

We had a beautiful 406 Ford catch fire in the pits with three Holleys. I hate them to this day. That was over 50 years ago.

[@tomschultz2833]

A tip for storing your spare o-rings is to keep them in the fridge. I remember before the reusable gaskets guys would cote the new gaskets with chapstick.

[@gmans7859]

I embrace the Therapy after my' fair weather only car' has sat. Take it apart, clean and inspect. Blue Gaskets, and I have never looked back after purchasing ARP Bowl Screws and use the Nylon bowl screw seals. Never over tighten anything. I would rather ' sneak up' on things if I catch weeping. My Tip would be get organized. Took some time but I have built myself a rather awesome simple Plano 3700 Tackle Box with damn near spare everything. When Monies allow, buy 2 when ya' need something. I use Carb Spares when I need something from Summit/Jegs as 'fillers' when I order.

[@kenwatts5410]

BLP Carbs in Florida sell o rings for the needle and seat made of Buna material for 35 cents, I use Allstate Carburator and buy everything else in bulk, at the end of the cruising season maybe drain the carb take it apart and vasoline the critical o rings and parts, just a thought.

[@hunnybunnysheavymetalmusic6542]

Suggestion: I have been swapping out all such O-rings on all my equipment with those green air conditioner type O-rings. While I can not promise this will fix the problem, I do find that in my situation, they seem to last longer and fit better, preventing leaks, thus far, without any other modifications to anything.

[@yurimodin7333]

Viton.....best oring material ever

[@mediumjumbo7484]

Carb videos 👍👍👍

[@jkline999]

If I have a carb, I run ethanol free. Big engine or small engine. My problems vanished. Thx for the vid, UTG!.

[@sydrider6023]

The accelerator pump cap will also get distorted with time and will leak. Not a flood leak but will create a yellow varnish on stuff under it associated with this slow leak. They can be sanded flat and reinstalled.

[@jackinthebox6143]

Also the accelerator pump diaphragm (?). They go rock hard in no time. Theyve brought in a new one made of something greeny bluish that's supposed to last. Online they were charging $50 each!! I think vaseline helps these things last but I may be wrong. It just seems to stop them drying out.

[@BDMase]

CAT o-rings. Decent quality

[@MrTheHillfolk]

1:29 My old TS 125 does that. Leave it sitting 6mo with an empty tank ,and fill it up and the fuel valve pours fuel out. So leave and come back 20mins later and it's stopped. Can't recall how many times I've seen it do that over the years. Let the fuel swell up the seal in there and it stops.

[@edge2sword186]

The problem is when they change the composition of chemicals at the pump without telling anyone .Back in the late 80's they changed the blend in premium gas and I had a new Holley spread bore melt the bowl gaskets with Holley have no fix to replace those gaskets yet . Saw 3/8 Fi line burst after melting from some new additives to pump gas and had 2cycle gas lines leak when using regular 2cycle oil with 10 % ethanol gas. They keep messing with blending of fuels without any warning . How many engines got ruined when the took the fines out of Motor Oils without warning ?

[@boilerroomed3682]

In the old days I would rummage around in a faucet valve disk kit for something close and trim it to size. Sometimes it actually worked!....

[@DanEBoyd]

Most carbs I've rebuilt ran better afterward, and none of them ran any worse.

[@weseethetruth158]

A simple trick if you don't wanna try and find the non stick gaskets is spray your gaskets with PB plaster before putting them on. Oh and stop using rubber o rings go to a fuel specific o ring.

[@blau325]

Also I see the accelator pump leaks when they set also.

[@moto_rad]

LOVE the carb videos. EFI nerds can go play starwars with each other to feel better

[@martehoudesheldt5885]

accelerator pump and power valve will dry and leak over time also. been there done that.

[@anthonypritchard7710]

Tony you should go through the spread bore carb. I have one and know nothing about it. Lol!

[@HansensUniverseT-A]

I just watched a video about leaky gut, looks like we're on to leaky things this time around!

[@warren4259]

The flange that holds the o rings in place is far enough back on the transfer tube to actualy put 2 o rings on each end. Just a little insurance, I've been stacking mine for many years and never had 1 leak.

[@bartorlans5390]

With so many gaskets and seals below the fuel level, they are designed to leak. The reason there are so many aftermarket parts available for them is that they need them.

[@broke_dongle]

Holley Golly, I double the o rings on the transfer tube. I drain and store carbs 😩 in climate control and wonder if I spray PB or WD through them helps?

[@cutl00senc]

“Don’t Be That Guy!” Put that on a shirt UT!

[@89ddx]

I use double pumpers, and I have had multiple accelerator pumps get dry rot and leak

[@Mike-sh2dg]

Thanks to Covid I can't smell gasoline anymore. This is a serious issue as a Holley owner. I'll probably go back to an Edelbrock or maybe even FI because of this issue.

[@thomashodges6104]

You can have the same thing with fuel injected cars. Where injector s mount to the fuel rail. The O rings dry out.

[@hunnybunnysheavymetalmusic6542]

I have owned 1 Edlebrock, and maybe... 12 Holleys? The only problems I ever had with Holleys was the O-rings, except one of those rare 500 CFM lean burn carburetors where it would have cost me more to buy a rebuild kit [513 and some change] than it did to buy a factory rebuilt 750 [ 275 bucks while giving them the 500 LB as a core (which they likely either just tossed it, or else found some rich collector who wanted just that specific model carb for a restoration)] and on top of being cheaper, it allowed my car to go faster.

[@guitareagle]

my brand new holley leaked right out of the box at first start up

[@lindoncoggins]

Random knowledge here. Chapstick is a part of my carb rebuilds. Every gasket gets chapstick applied to it, should a roadside repair need to be done, the gaskets will majority of the time be reusable when previously coated with chapstick. Marvel Mystery Oil is also a storage must. Every carbureted thing I have gets run on straight MMO before being put up for an extended time.

[@randalfernandez2534]

Is there a video about setting valve lash a step by step?

[@bloodhawk6252]

Chapstick will keep the gaskets from sticking .For Orings I go to the local farm service

[@truthboomertruthbomber5125]

It’s unfortunate that the Autolite style aftermarket carbs have quality control issues.

[@AtZero138]

Carb Talk Corner with Our Uncle Tony.. Come get some.. @∅

[@blau325]

Thermoquads have X ring o-rings at the bottom of the primary wells. Yes alcohol(ethanol 10%}dries out the non nitrile o-rings.

[@clembob8004]

I get the whole Holley carb thing for high performance, but I'll stick with my Carters and Edelbrocks and live mostly trouble free.