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Old 03-31-2011, 08:03 PM   #26
86shortchevy
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Re: edelbrock problems

just pulled the carb off. intake is infact square bore and dual plane. before i took it off i started it up and it idled fine, reved fine etc. turned it off, and it wouldnt start back, so i let it sit about 20 seconds and it would try to start as it would turn over, but wouldnt crank. its very inconsistent. when i did get it to start it was choppy and spat and sputtered for about 10 seconds and required me to pump it to keep it running. it smoothed out after a sec and idled fine. so is this a timing issue? im baffled
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Old 03-31-2011, 09:09 PM   #27
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Re: edelbrock problems

What's yer fuel pump pressure?
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Old 03-31-2011, 09:15 PM   #28
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Re: edelbrock problems

Almost sounds like a float problem too.
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Old 03-31-2011, 11:00 PM   #29
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Re: edelbrock problems

i checked them yesterday but i will recheck to make sure. not sure on fuel pressure.
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Old 04-01-2011, 11:35 AM   #30
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Re: edelbrock problems

The post at the top of this page is really starting to sound more like a distributor problem, and just a coincidence that it happened when you swapped carbs--did you change anything to the distributor other than connecting the vaccuum advance (bumped the cap, etc)? Is it still points or electronic?

Also, when you took it off did you check the throttle plates?

When you put it back on did you reset the mixture and idle speed screws? Did you find anything else that the linkage--on either side--could be hanging up on when the truck should be idling?

You did say that you had rebuilt the Eddy a few times, but the most recent time what method did you use for cleaning? Did you blow out the passages with air before reassembly? Lastly, did the accelerator pump look god or dried out? Rubber (pink) or silicone (blue) seal on it (or leather from a lucky rebuild kit)?

I hope we can get this sorted out for ya.
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Old 04-01-2011, 04:58 PM   #31
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Re: edelbrock problems

the accelerator pump is brand new. i rebuilt it like 2 months ago.

about the distributor. now that you mention that, i just remembered that when i was changing my spark plug wires last week i did notice that one of the terminals on the distributor was a brown color, only that one though. It is HEI i believe because i have not seen an external coil. the problem was still occurring before i changed my wires too so its not my wires.

thank you guys a ton for helping me figure this out
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Old 04-01-2011, 07:10 PM   #32
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Re: edelbrock problems

so i just went out and checked the dist. cap, turns out that 3 of the terminals were coroded and crappy. i took some steel wool to them and made em shiny again. the truck cranked right up and idled great without the choke even pulled. so i decided to take a drive to autozone to grab a vaccuum gauge. started up great, im driving home and it just cuts off in the middle of the road. we tried to start it for twenty minutes and it just wasnt going to happen. My buddy came and picked me up and the truck is still sitting in the parking lot. its getting gas no doubt. it has to be electrical. did it jump timing? wtf?
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Old 04-02-2011, 02:11 AM   #33
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Re: edelbrock problems

A GM HEI, or nearly any electronic ignition, generates enough voltage to arc directly through plastic like the kind used to make caps. Electricity follows the path of least resistance though, so the engineers try to ensure that the least resistance takes the electricity to the cylinder desired. rotors, contacts, and wires are how this control is attempted.

If the cap terminals were corroded first, then the electricity meant to travel through the terminal started looking for an easier path to follow, like to the next terminal to the left or right of the bad one. This is what "arcing" refers to, as it will arc across plain air or through the cap itself. I am sure when you take the cap off you will see the inside looks like it has been eaten away.

Before hunting down any other problems, lets fix the known issue. Replace the cap and rotor, which are both now damaged. When you reassemble everything make sure it goes back together as intended. The rotor button (in the cap) should actually contact the center lead on the rotor as it turns, etc. Make sure every wire seats properly on the terminals. Then we'll see what the condition is and if any more tuning or troubleshooting is needed.
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Old 04-02-2011, 05:49 AM   #34
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Re: edelbrock problems

when you have the rotor off make sure the weights move freely
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Old 04-02-2011, 10:50 AM   #35
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Re: edelbrock problems

alright ill definitely try that today. ill report back after. thanks
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Old 04-03-2011, 01:40 AM   #36
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Re: edelbrock problems

replaced cap and rotor with new msd. and replaced the hei with an accell. problem seems to be fixed, ill see how it runs for the next few days. thanks for all the help guys
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Old 04-03-2011, 01:16 PM   #37
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Re: edelbrock problems

Glad we could help, and hopefully that solves what was ailing ya. What tune did you end up with for the Eddy?
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Old 04-03-2011, 09:32 PM   #38
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Re: edelbrock problems

pump rod in the closest hole to the pivot. about 2 1/2 turns out on the mixture screws. drove it around town today and it didn't give me any trouble. so hopefully its fixed
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Old 04-07-2011, 08:35 PM   #39
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Re: edelbrock problems

well its still acting up. seems like its been getting worse the more i drive it. ran great for a couple days. now today its doing the same thing it was doing. takes forever to get it cranked and when it does crank it will barely run for a few secs then it will smooth out.
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Old 04-07-2011, 09:46 PM   #40
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Re: edelbrock problems

Pull the new cap to see if any damage has recurred. Also, what kind of fuel filter are you running?
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Old 04-07-2011, 10:42 PM   #41
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Re: edelbrock problems

filter looks like this. if there is damage to the new cap what would cause it?
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Old 04-08-2011, 11:38 AM   #42
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Re: edelbrock problems

Vacuum leak ???
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Old 04-08-2011, 11:40 AM   #43
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Re: edelbrock problems

That's an OK filter for now, while we're ironing out the "bugs" because we can see through it, but remember it doesn't meet GM specs for the GF61 filter nor NSRA safety specs, both of which require a metal housing. That particular one is a Chinese "equivalent", which at first makes it suspect, but I use similar products from NAPA (made by Wix though) while checking my fuel systems out (then swap later too)

How's it look? anything floating in it? Looks like it's coming apart or clogged?

If the new cap is being eaten alive, my first place to look would be the assembly for the button and bushing under the coil. The button should protrude through the hole in the cap by enough to contact the rotor, about 3/8 of an inch. I say check this first because it is a precaution usually overlooked and I've had one that was wrong (the bushing was sandwiched between the button and cap instead of between the coil and button like it should) but this is not the most likely cause.

More likely, something is causing more resistance to passing the spark through the correct path than the incorrect paths offer.

Check your plug gap, it should be .045" or very close (do not exceed .055" on mild engines) and each plug wire needs to be seated with a firm "click" on the ends of the terminals and plugs. Check each plug wire for burns or indications of heat. If you know the specs for your plug wires, check the resistance with a multimeter or voltmeter. For 20000 ohm resistor wires, you should max out about 12 ohms on your longest wire.

Remember, only go to those lengths if the cap is going bad again--but CHECK the cap.

Most likely of all, the new cap will be good. I'd bet the plugs are fouled, either from not warming up still or from the earlier trouble. Check the filter and cap and then go on to check the plugs either when you pull them as above, or on their own if you did not have to pull them above. Notice I listed the order of events based on what takes the least time, money and effort; not the most likely. Even if you get to pulling plugs and find them dark and sooty or anything else that still looks "rich or incomplete" you can buy a set of Autolites cheap still nearly anywhere.

If the last situation is the case, looking at leaning out the carb up to a half turn at idle, resetting timing, or just making sure you drive the truck long enough to come to full temperature (burn the plugs clean) before any more radical measures. We'll see how this turns out and hope to hear good news from you soon!
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Old 04-08-2011, 12:24 PM   #44
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Re: edelbrock problems

Quote:
Originally Posted by 86shortchevy View Post
takes forever to get it cranked and when it does crank it will barely run for a few secs then it will smooth out.
You say you bought your carb used...

My 1406 had this exact problem, especially after hot starts (the truck had sat for a few years before I bought it). The shop that fixed it replaced the needle valves and blew crud out of the carb and well as installed a carb spacer. Don't know if this helps but thought I would throw it out there...
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Old 04-08-2011, 12:50 PM   #45
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Re: edelbrock problems

You need to check out Edelbrocks tech videos. It makes adjustment easy.
http://www.edelbrock.com/automotive_...ech_vids.shtml
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Old 04-08-2011, 12:56 PM   #46
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Re: edelbrock problems

I have another thread going with a similar problem, except I have a Q-Jet. Turns out, my carb was all nasty inside and had an internal vacuum leak. I took it to an experienced mechanic well versed in Q-Jet's and he rebuilt it for me. I put it back on and the truck is running perfectly.

I would certainly check the manifold vacuum and adjust the carb that way as stated earlier in a previous post. Try to stick with only changing one variable at a time. It seems like there are several issues and several items being moved around all at once.

I hope this helps and good luck in getting it fixed. I know it gets discouraging but hang in there...The good folks on this forum will help you figure it out.
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Old 04-08-2011, 08:14 PM   #47
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Re: edelbrock problems

i do notice some bubbles in the fuel filter, is that normal? ill will check all this stuff asap but i have a feeling its jumping timing or something. thanks for all the help guys
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Old 04-09-2011, 12:46 AM   #48
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Re: edelbrock problems

Bubbles of air in the gas sitting in the filter is normal, especially after shutting off the engine; bubbles in the plastic housing indicates either poor manufacturing or exposure to heat and a need to replace the filter before it fails.

I was actually hoping to hear that some crud was floating in it, which would indicate a need to replace the filter anyway but also explain some of the rough conditions because of how easily the same crud would get in between the needle and seat.

There's ways to determine if the timing is jumping, later. It may even reveal itself if you try to reset the timing to prevent a recurrence of fouled plugs--or it may not show. Looking for the expensive fixes first will lead you to find ways to spend money on expensive fixes first--even if the problem is an inexpensive or easy one.

We'll have to see what you find before we move on though.
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Old 04-09-2011, 07:00 PM   #49
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Re: edelbrock problems

when i was checking things today i noticed my spark plugs were tiny. took them to get matched and they turned out to be weed eater spark plugs!!!!!!!!!!!! the studid **** before i got the truck put them in there because its the only ones that would fit with the headers on it. i took the headers off and am now looking for different ones
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Old 04-10-2011, 01:53 AM   #50
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Re: edelbrock problems

Well I guess that would explain part of the problem, sounds to me like they didnt wanna pay or didnt know that there are plugs made for headers.
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