I need edelbrock carb help please.

my dad has got a chevy zz3 350 in his 54 stude truck. its got a 600 edelbrock carb. its been trouble free for about 10 years. now , at idle it seems to be running on 4 cylinders. when you ease down on the throttle a little it kind of skips and stumbles and then all of a sudden it runs great. i have taken the top off and examined the floats and needle and seats. there is a good amount of trash in the float bowls and in those little screens.i'm gong to clean and blow out the whole thing but i would really like to know whats wrong and pinpointing the problem instead of cleaning it and hoping that its fixed.it seems to me that its in the idle circuit.thanks in advance.

 

That's interesting that you post this, because that's the exact and I mean exact problem I've been having lately on the 600 Edelbrock on my Nomad. Run horrible at idle and low rpm and then at a certain throttle position it runs great. I think it's idle circuit, too, after reading an online Performer carb PDF from Edelbrock, and idle circuit is still involved at lower rpms.

My carb has been on the car for 11 years, driven regularly. Today I bought an Edelbrock carb kit and my guess is it's trash in idle circuit as well. I guess I'll find out.

I'm also gonna take a good look for vacuum leaks as well, and put my vacuum gauge on it to see. Let me know what you discover and I'll do the same.

 

i had this same problem on the coupe i had. i took it apart and cleaned it. it ran great. but what did i fix ??? will do duncan.

 

take the air & gas mixture srews out sqwart some carb cleaner in the holes real good. Put it back together. make sure you count how many trune out the srews are so you can get it back close.

 

The gas we get from anyone is dirty, use a good filter and change it often. I have a lot of afb style carbs and dirt is your enemy its all that goes wrong with them that I have found.

 

I think ethanol content is causing alot of us problems like this. Same issues with the 650 Edelbrock on a 360 Mopar. Seafoam seems to help clear out the crap.

 

I think not rebuilding your carb for 10 years is asking too much. Lol

 

I am having the same issues. going to rebuild carb next week. hopefully thats it. I will watch this post to see.....

 

It the crap fuel that dose it. It turns bad in about 3 months buy drawing water into it. It's the ethanol that's bad. You need to use stabil to help keep it clean. They even have a new blend just for this. So clean out as much as you can and you will be good.

 

I,m coming over to the states in 4 weeks and one of the things I was going to buy was an edelbrock carb ,are you guys happy with your carbs as compared with a Holley.I have heard the edelbrock is better for street use ,what do you think........

 

I had the same problem with a 625 AFB . I rebuild mine so it should be fine now .
Don't you just love the great Ethanol fuel we have to use ? Does suck good things to our fuel systems !

Retro Jim

 

clean the damn carb.

 

I've had both brands of carbs. I prefer Holleys. A Holley 650 vacuum secondary sits atop the Chevy small block in my '31 ford coupe. Works great!

 

i guess i don't know enough about how a carb works. why is it sounding like a 4 cyl. at idle. i have had this happen before on my car. yea, i need to clean the damn thing.and it hasnt been touched in about 10 years because its my dads and its been running fine. now that he's getting up in age, its been sitting and not getting driven and i think that could be part of the problem..........and good captain, i prefer the edelbrock.

 

Trash in the carb is not because of ethanol in the fuel. A good inline filter is a must, but if the tank has trash in it the only cure is to clean the tank.

And; the only thing better than a Edelbrock 600 is two of them.

 

Take it completly apart clean with carb cleaner,make sure to blow it out real good with air ! sounds like some shit in the low speed jet to me. Not much to it,simple carb. Like said here I would make sure to have a filter before and after fuel pump.

 

Yes the Edelbrock carb is perfect for street use and dependability.I gave up on Holly since I seem to have had problems with them in the past. I run Edelbrock on all my cars.

 

A friend of mine is having the same issues on a stock 305. I told him the same thing.


I hate Edelbrocks. not just performance wise but they just don't look right ether. I had a customer bring me his 73 vette ( bone stock) He had put an Edelbrock on it a few months earlyer. It would start right up even after siting for weeks with a few pums of the throttle. It ran smooth down the road but just didn't have the power it should have.after tuning, jeting and messing with it it ran no different. I put his dirty Quadrajunk back on and it was day and night. It came alive and he got his fuel milage back to.

I prefer Holleys for their performance and they just look right. One four, two fours, three twos, in line or side ways.

 

i have got an edelbrock 600 on my 40 merc and coming home from indy last year it starting running rough on idle. took the carb off, cleaned it and the secondary venturi booster on one side looks like it melted part away any ideas out there what caused it it is this new fuel????

 

I see a lot of carbs and i believe that a cathodic reaction is going on inside where the water reacts to the exposed pot metal. This is a worser problem in hollys than edelbrock, the edelbrock seems to have a better coating and protection. A customer brought in a pair of hollys for rebuild and upgrade, this is the worst case i have ever seen. When i opened the rear bowl powder just dumped out and this is what is left. I call it 'white death' and see it often. Once it sets in you can't really stop it, it'll usually start in the bowl itself - maybe the screws are the starting point - and continue to spread to the metering block.
Like another said i advise to use stabil in the street cars, race cars i suggest to dump out all gas and replace with wd40. Avoid letting the carb dryout.

 

Take the top back off,remove the primary boosters and blow them out. The idle jet is the small tube in the center,so make sure that's clear. You'll see how small it is so it doesn't take much to clog it.

 

Thanks to all of yall who took the time to comment. I'm learning alot. Yea , i agree, they dont look right, but i still like them edelbrocks[ really carters].

 

No, three of them, and make them 750's.

 

Be careful with the idle mixture screws, more than one carb has been destroyed by someone cranking down on them with a screw driver, and cracking the bottom of the carb... They should only be seated lightly, then back out 1 1/2 - 2 turns.

 

I had a talk with a small engine mechanic about carbs, he thought that the new gasoline with the alcohol is wrecking the seats and seals in all carbs. His advice to me was to starve the carb out of gas, easy enough, and shoot some fogging oil into the carb so the alcohol could not eat the carb up, the alcohol turns to water I guess. He recommended replacing the seals every 2 or so years. So if I am not running the car for a couple weeks I fog it.

 

Has anyone tried StarTron Enzyme fuel treatment? Made by Srarbright. It helps combat Ethanol problems in gas and diesel fuel.

I started using it in our choppers that sit during the winter.I've also started recomending it to my customers who have noticed an improvement in their daily drivers and cruizers.

This product might of been posted on another thread but I feel it relates to the issues in this thread also.

 

i think you are right. i did what you said and so far its running good. thanks.

 

1000 x ditto!!

 

That carb has 40 year old gaskets on it... Who knows how long it's been sitting.... That's sad..

 

All the fuel comments are pretty much right on, gots to keep it clean!!!

Another thing I have seen on more than one car is the vacuum line to the distributor plugged into the wrong port on the Edelbrock carb.

World of difference when you get it correct!! Take care, K