How to Fix Heat Soak in a Carburetor

so what's causing your carburetor to boil over with fuel and why is it hard to start when it's hot more importantly how can it be corrected so we're gonna take a look at that today and some things you can do to keep your carburetor running right let's take a look at it so what's causing these carburetors to boil over it's heat and it's ethanol ethanol is the biggest problem with today's carburation now most vehicles today run on fuel injection you don't have this issue because you're running at a higher pressure ethanol doesn't have near the issues that it does an old analog non-pressurized system like a carburetor is when you bolt a carburetor directly to an intake manifold you are putting it directly onto the heat source the heat comes up from the combustion event out of the cylinder head through the intake manifold directly up into the carburetor and that's where you're running into these problems ethanol boils at a hundred and eighty degrees and we've talked a lot about ethanol in the past in this carburetor series doesn't matter what brand of carburetor you have you're going to run into these problems and the solution for it is universal it doesn't matter what brand of carburetor you're running so we've got to isolate the heat from the cylinder head and the intake manifold to cure this problem and that's what we're gonna do here and that's where I'm going to show you how to take care of today isolating the heat and try to keep it as far away from the carburetor as possible so this is a rubber composite material gasket essentially but it's a little thicker that goes in between the intake manifold and the carburetor and what it's designed to do is help isolate a little bit more of the heat breaks it up helps it not transfer up into the carburetor up into little fuel bowls if that's in there so just like any other little spacer you know the the thicker you can get these the better now I think this is just a little over a quarter inch thick or so but you know if you can run a half inch spacer or run it if you can run a one inch spacer run it if you can run a two inch spacer run it the better the you know the further away you can get to carburetor away from the intake manifold the better so that's what this is designed to do it's very very thin and sometimes when you don't have a lot of room underneath the hood these are the best little option and here it is installed on the intake manifold again it's not that thick but it's enough to help keep the heat away from the carburetor and then like again like I said you know the thicker the space are the better I know under hood clearance is tough on on some vehicles the a body is is typically a half inch spacer you can get away with on a big block or a small block and typically just depends on how thick your air cleaner is but again anything you do to isolate the heat from the carburetor that's what these are designed to do now I also want to talk about regulating the fuel a little bit with a fuel pressure regulator obviously it has a job to send the right amount of pressurized fuel to the carburetor but in this instance and this is a non regulated or excuse me an on bypass regulator so you just have to kind of you know imagine how this setup is you've got one Inlet typically two outlets and then one bypass outlet that goes back to the fuel tank so it the idea is that when the pressure the fuel is not needed to the carburetor it sends the fuel back to the tank or theoretically it keeps it cooler now there's a couple lines of thought here that if you've got at the drag strip and you've only got two or three gallons of gas in the tank you're just circulating hot fuel back into a hot tank and it doesn't have time to cool off so that's one way of looking at it if we go back to our fuel system that we've referenced a couple of times I'd talked about this exclusively in the ultimate tuning guide but what you're really trying to do here is just keep the fuel moving within the system and there's a decent line of thought there you know if you've got a mostly full tank of fuel the fuel is probably cooler in the back of the car than it is closer to the hot engine bay and by sending the fuel back you're not using back to the tank where it stays hopefully a little cooler I can see a benefit there but it just all depends on the application so those are two kind of ways that you can kind of help isolate the fuel from the hot intake manifold and keep it a little cooler now there's other things you can do you can wrap the fuel lines the chevelles got that down on you can see here you can route the fuel lines away from hot exhaust headers turbo charger or whatever the case may be you can run one of those old-school Moroso cool cans where you know it's kind of like a coffee can with a coil of fuel line in it you throw ice in there help cool down the charge that works but it's kind of limited more of a drag strip type of thing like we just talked about a minute ago but you know the whole idea here is to help isolate the fuel when you do that those hot start issues go away very quickly because of the ethanol like we talked about is not boiling in the bowls of that carburetor so it makes it a really really cost-effective easy simple way to just try to control the heat that's getting into that carburetor so like I said there's there's plenty of different you know little tricks that can do but you know your your whole idea here is is you know just to try to plan your way out when you bolt that carburetor directly to the intake manifold all that heat transfers directly into the carburetor aluminum transfers heat very well and these aluminum bodied carburetors suck up the heat very well out of the intake manifold so you've got to find a way to isolate that so I hope you found this useful these hot summer days they were experiencing right now you know it's it's it's gonna happen you're gonna run into these problems if you're running a carburetor directly onto the intake manifold I know might not look as good as you want to but hey when the hoods closed you're driving down the road you never see it anyway so I appreciate ya'll watching drop me a comment down below if you've experienced this before some of the things you did to fix a problem as always if you thought the video is cool please me a thumbs up and subscribe if you haven't and we will catch you all in the next video thanks guys see ya

Channel: Muscle Car Solutions

Views: 9,213

Rating: 4.9529409 out of 5

Keywords: edelbrock, carburetor, heat soak, hot start, edelbrock carb, holley, holley carb, quick fuel, demon, quadrajet, brawler, fuel boiling, flooding carburetor fix, carburetor tips and tricks, carburetor installation, holley carburetor flooding, how to stop carb flooding, fuel boiling over

Id: sXY4t8LSwjs

Length: 6min 49sec (409 seconds)

Published: Tue Jun 30 2020