I really need some help with figuring out what the Hell is wrong with my Edelbrock carb. If it sits overnight, I have a hard time getting the engine started. Once it starts the first time, it'll start every time after that, all day long. This is a new development, and it's got me stumped. All it takes is just a whiff of carb cleaner, and Bam! it starts immediately and will idle all day, and runs good. The choke is set and works really well, and I checked the accelerator pump....it's working, too. I replaced the fuel pump, thinking maybe the old one was allowing fuel to bleed back through it, but it didn't make a difference. The fuel filter is clean. Any ideas?
Do you have one of the insulators between the carb and the intake? If not, it's possible (likely ) that most of the fuel is boiling and evaporating out of your carb. Today's fuels with ethanol have a very low boiling point. I mean really low. I wouldn't have believed it if I hadn't seen it on my Buick.
X2 on a phenolic insulator and maybe even a heat shield. pretty much every car i've had or worked on had that problem with edelbrock carbs.
If I'm not mistaken installing that plate is a suggestion in Edelbrocks instruction manual. I ran without it for 2 days and my engine ran bad.
No problem with the gas cap. It worked fine for months, then all of a sudden this problem popped up. I do have a spacer under the carb, same as it's been since I got it, but it's not phenolic. We had talked about it, and decided it was okay as there had been no problem. I'll put one on and see what happens. A friend also suggested an o-ring at the venturi might be bad, allowing gas to siphon. Thanks for all of the suggestions!
There is no way the fuel in the carb can go back to the tank so it must be boiling or evaporating,in the morning just crank it over until it starts reading oil pressure then hit the gas and should start. I have to do this when I let my F250 sit a few days and it has a edelbrock.
The fuel pump works fine. The only time it acts up is when it's sat overnight. I can drive it a hundred miles, park it, and come out three hours later....it starts immediately. So it doesn't sound like the gas is boiling out if it only runs for five minutes, sits overnight, then won't start but runs for over two hours, sits for hours, then starts right up. Whatever it is takes ten hours or more to occur, so it seems more like a leakdown than gas boiling to me.
This seems to be a problem with a lot of Edelbrock carbs lately. I know of at least four around here that have similar issues. Most of them are setting on shelves now. I replaced mine with a q-jet recently.
I haven't had one of those Carter/Edelbrock carbs apart in a long time. Do they have well plugs on the bottom like a Q-jet? If so, maybe they have started leaking?
I don't use starting fluid. It takes just a small whiff of carb cleaner and it fires right up and will idle as long as I let it.
I recently added a 1" wooden spacer to mine & it fired on the first crank, when it would normally crank & crank to the point of running the battery down after it sat. It actually seemed to remedy a couple issues w/ the Edelbrock.
I have three cars with Edelbrocks, they all do the same thing. I did put a insulator on one and it does not do it now. I do have another one on a pick up that I have not driven in years and it never did it, the only difference is it has an electric fuel pump. I think evaporation is the problem.
I would pull the top of the carb after it has been sitting all night and see if the bowl has fuel in it. If it is empty then it is evaporating, boiling or leaking out somewhere. If it is full of gas then it must be a tune or ignition problem. I would think if it was leaking outside of the carb you would have a nice mess on the manifold and if it was leaking into the manifold you could look down the bores and see it puddled on the runners. I would think it would have to be some pretty volatile fuel to evaporate to the point of being empty overnight, and even then a couple of revolutions on the starter and the bowls will be full and it should start, having to use even a little starting juice or carb cleaner says that the tune is off at start, maybe to rich and it being choked floods it pretty quick.
The part that confounds me is that when I first set the choke, it would start every time, almost before it had turned over the first time. Day or night, overnight, whenever, all I needed to do was hit the throttle once to set the choke. As soon as I hit the button it was running. It does the same now, except for first thing in the morning.
Mine does the same thing except if it sits for 2 days instead of 1 it won't start. Mine is an older 1406 before the days of ethanol additive and now it needs a rebuild kit with the newer (ethanol friendly) accelerator pump because now even after starting it with ether I have to feather it a lot. Like the others I'd suggest the phenolic spacer and add an electric pump. BTW, the phenolic spacer is made from material like the heat shields on the space shuttle. A division of the company I worked for made the resin.
how old is the gas? if it sat all winter that may be the problem, the new gas with alcohol should not be stored in metal containers (gas tanks) for long periods of time
This will sound nuts, but the new gasolines are evaporating at a higher rate than any of us thought. When we come back to our shop with our hot rods they always have at least a quarter of a tank of fuel in them, but a few weeks later when we go to drive them, the tanks are on fumes and we have to get to the first gas station we can. My one Son thought we borrowed some gas out of his tank one time because he stored it with a full tank and when he went to use it a couple of months later the tank was super low. We got a little pissed because it was as if he was asking if we siphoned some gas out, but after our tanks started doing the same thing we kind of understood where the gas was going. That is what is happening to your Edelbrock. When we start our cars after being stored for a while we have to let the electric fuel pumps run for a while to fill the carbs back up. Don
thats crazy^ Don, i never noticed before but come to think of it, I always go to the gas station first thing when i take my car out, but i don't remember it being low when i put her away lol
That makes sense. The fuel in the car is only a week or two out of the ground. Weird thing is, when I went over to the shop today, it started right up. It's been sitting since Tuesday, and started as soon as I hit the button. Now I'm really confused!
Try this, and bare with me. You say it only does this in the morning. Okay, assuming you park it at 8pm and don't get out until 9am, that's 13 hours. Try reversing it. In other words, drive it in the morning for an hour and park it. Then, try starting it at 9pm. See what happens. Basically, something is happening in that 13 hour period like evaporation. . Pointless? Maybe. But you seem to have tried everything else, maybe it's time to try the crazy stuff.