Another Edelbrock issue

[67ChevyRedneck]

1406 w/ Electric choke.

[Steeveedee]

Originally Posted by 67ChevyRedneck

Crap, no. I hadn't thought of that. It does have a lot of miles on it.

Would I be able to feel a little pull, or do I need to spray carb cleaner to check?

I've had a couple of them, and you can't tell anything by pedal pull, if that is what you mean. If you mean pulling the throttle arm to find it, maybe that will work, but I don't know. It might even take a squirt on the passenger's side of the carburetor to locate the problem. They develop the problem in about 30,000 miles, in my experience.

[akart]

Originally Posted by 68 P.O.S.

Need your truck particulars. What year is your truck? Which engine is in it? Stock engine or beefed up? Points or HEI? Any recent work done to it that may affect the problem you have? Have you checked for vacuum leaks? Checked your fuel system for clogged filter or sending unit sock, kinked or worn lines, and fuel pump ok?

How’s your timing? If it’s not set correctly before you start working on everything else, you’ll be chasing your tail.

Edelbrock carbs are known to be a little finicky and are not exactly plug n play out of the box (what carb is?). Once setup correctly, they are a great carb. If it’s an older carb, it’s probably a good idea to clean it out real well and rebuild it. Then adjust float levels to specs, add a heat insulating gasket between intake and carb to stop carb boil, add a Edelbrock fuel pump or a fuel pressure regulator set to 5.5 psi to prevent flooding, set the transition slots to square, buy a calibration kit to dial in jetting/rods/step-up springs, and enjoy.

All of this and buy a new carb 1405 w/a manual choke. They are
cheap enough and a new filter. That's what I did. Good luck.

[6768chevylover]

Okay. Changed the fuel pump and another rod in the carb. It seems to be running better and plugs look ideal. Took it out for a little rid and everything seem to be okay till I got near home and it gave a little sputtering not as much noticeable as before and as long as before. Anything else I should be checking? This is getting annoying. I noticed an exhaust leak at the collector on the driver side. Its a stock exhaust manifold. Would this be causing the issue?

[68 P.O.S.]

Did you ever adjust your timing? Since you have the L31 Vortec heads, they like about 32 degrees total timing.

[6768chevylover]

I have the timing set to 34 degrees total.. Im guessing I should back it off a bit..

[6768chevylover]

I set the timing with an advance light setting it to 34 degrees on the light, and 3000rpms matching it to the tdc(0 on balancer) on the timing tab. When I check the timing on the balancer markings(34 at 3000 rpms) with the light set to 0 it doesn't match the markings on the balancer. Is this a problem?

[68 P.O.S.]

34 isn’t bad if you have no pinging. Play with it a bit, but the sweet spot for Vortecs is supposed to be about 32 degrees. Yes, your timing light should match either way you do it, so something’s not right. Maybe the distributor advance springs are too strong and aren’t allowing full advance at 3K RPM. If they are the original springs, those things are way too strong and don’t allow full advance until about redline. You’ll have better luck pulling the springs out, then re-timing it and see if there’s still an issue. Have you verified TDC with a piston stop to make sure the balancer isn’t slipping? Since you replaced the spark plugs, did you gap them to 0.045 for HEI? Did you did replace the plug wires as well?

I just re-read this thread and in your first post, your description of having to blip the throttle to bring the rpms down just reminded me I had a problem like that once. I would start the truck and it would idle at 750 as normal, then after going for a drive and parking, the idle rpms would be at 1000. Would have to blip the throttle to bring it back down. What fixed mine was pulling the carb off and squaring the transition slots. Also, adding a CDI box like a MSD will really smooth out your idle too.

[6768chevylover]

I did determine top dead center on the balancer with a piston stop. I have a Davis Unified HEI distributor, new plug wires new spark plugs that are gapped at.045.. do you think that the springs on the mechanical Advance are strong on this type of distributor?

[68 P.O.S.]

Well, sounds like TDC is good to go then. With that HEI, I don’t know what kind of springs they put in there since DUI custom tunes each distributor for your engine specs. Did you buy it new or used? Since TDC is good, the springs being too strong is all I can think of at the moment.

[akart]

Originally Posted by 6768chevylover

I did determine top dead center on the balancer with a piston stop. I have a Davis Unified HEI distributor, new plug wires new spark plugs that are gapped at.045.. do you think that the springs on the mechanical Advance are strong on this type of distributor?

I have The DUI and I think they are the best. I wouldn't be concerned about spring tension. They suggest a .050 gap. And they don't tune each one custom to your engine. They just give you a good average and suggest a 12 degree advance to start with and advance a little at a time till the engine talks to you. You know like knocks/rattles then back off. I noticed a boost in power w/the DUI.

[6768chevylover]

Took the truck out for a ride today. I'm starting to think its a bog that im experiencing. Its only seems to be in 4th gear. I decided to put a 93 octane in it and it seems the bog is going away. Does this sound like an e85 issue?

[6768chevylover]

Still having an issue. Decided,to take a look at my distributor . Took it out and,layed it,on the ground and gas poured,out the VA. What does that mean?

[geezer#99]

Originally Posted by 6768chevylover

Still having an issue. Decided,to take a look at my distributor . Took it out and,layed it,on the ground and gas poured,out the VA. What does that mean?

It means your vac advance is blown and your carb is flooding.

[68 P.O.S.]

Geezer is correct. You previously said you were gonna replace the floats, did you ever do that and set set them to spec? Perfect time to get the Crane 99600-1 adjustable vac advance kit.

[fdbdw]

Make sure you set your floats, upright and inverted, Super easy takes 5 minutes. Also make sure you’re not getting more than 6psi fuel pressure

[6768chevylover]

I set my float to spec cause they were not correct when I opened up the carb. the floats were fine as in no cracks or fuel in them. I was worried at that time if they were full of gas. pressure is at 5.5psi. I think my issue was the distributor VA but due to the floats being wrong the time before I had issues. It just tricked to another issue as well. I took a VA off another HEI dis. I had laying around and it seems to be working better. Now I need to recalibrate the carb since its running better. I leaned it out and now I need to richen it.. I'm gonna look into the crane adj VA... Thanks guys..