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Discussion Starter #22
So you've tried just turning the key to "ignition on" a minute or two to "prime" it before actually cranking the engine?
Correct. I actually gave it an entire 5 minutes to prime this weekend and it still didn’t wanna start.
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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Well not just a simple case of drainback then, for sure. Hmmm.
 

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Just a shot in the dark. Maybe your accelerator pump diaphragm is a little dried out. And after sitting up for a week all the fuel evaporates. Then it takes a little bit for the new fuel to soak and seal the pump diaphragm. I would turn on the fuel pump until you are sure that the carb is full. Then look into your carburetor as you manually cycle the throttle and verify that you are getting a good squirt of fuel via the accelerator pump. Again just throwing an idea out there.
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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A good theory. I'd add that it may be that the diaphragm could just be just plain bad altogether.
 
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It’s not flooding it, that much we’ve checked. I’m no rookie when it comes to motors, I built this one myself and it has been faithful for 12 years. I suspect, as you said, that something is sticking within the carb, whether it be the float not letting the fuel bowl fill up or maybe the accelerator pump. I just don’t know how to narrow it down. I’ve thought about rebuilding the carb but I’d hate to go that drastic because as I said, the thing runs great after I eventually do get it started. And like sitting overnight is no problem, I went and fired it up this morning with no issue.
open gas cap before cranking after waiting a week and listen for a vacuum . you may need a vented gas cap. if not vented your tank after driving will suck full trying to relieve neg pressure after driving around. happened to me once
 

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Discussion Starter #29
Do you drive this year round or just seasonally?
Just seasonally. I’m in Illinois so we get some brutal winters.
 

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Discussion Starter #31
Did you ever figure the issue out?
I have not figured the issue out yet, I’m going to get it out this weekend so we’ll see how it starts then, though I’m not holding my breath.
 

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Discussion Starter #33

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Cool. It will for sure tell you whether it's a fuel problem at least. Then you can go from there.

If it doesn't fire that way you may be looking at some sort of electrical gremlin. Unlikely but possible if not a fuel issue.
 

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WWRD? Next time before anything else, work the throttle and see if it gets a pump squirt. If not Turn on the pump and within a minute it should fill the bowl and be able to squirt. You gett pressure within that time right?
If not the only other things I can think now is the needle is sticking closed which is the opposite of normal problem for them.
If you have rubber lines you might use a translucent filter for a while to verify the rate it gets fuel to the top.
 

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Did you dump a bit of gas down the carb yet??
This is typically what works for me. I'm sure I have some carb issue since the idiot who rebuilt it probably had no clue what he was doing...yeah ok, it was me. First time I tried to start after that, fuel shot straight up. Float not set properly...

OP, sorry to hear about your issues, but glad I ran across this so I can try the same suggestions.
 

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Seasonal driver, I do the same thanks to winter.

I had an Edelbrock that was only started and run to operating temp for several years.
When I finally had the opportunity to start driving again, it ran great.
Within a week, it started to stumble at idle and eventually died and couldn’t start.

The eventual problem was the varnish in the fuel bowl had literally sloughed off the side walls and plugged up passages.

I was able to clear passages with carb cleaner.
After through cleaning, it started up immediately.

In my process of troubleshooting, I even used compressed air on steel lines on the car isolated from pump and tank. It did it in both directions to ensure it wasn’t plugged up, a small amount of crud did come out before using carb cleaner as well.

Hopefully something simple to fix so you can enjoy it again.

I also make sure i have the “no ethanol added” during winter storage as well.
 

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Discussion Starter #38
So I went out this weekend and it wouldn’t start as usual. Then we hit it with some starting fluid and it started right up. So it’s definitely a fuel issue of the carb not letting fuel into the intake. Any ideas? I’d really like to avoid rebuilding the carb considering it’s got like 10k miles on it.
 

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it could have zero miles on it and if sits with ethanol fuel in it will be useless. You could have rebuilt this thing 3 times with the time you've spent posting on the subject. It's a seriously simple issue as everyone has told you it's a fuel issue there is not fuel in your fuel bowl or it's not pumping out for whatever reason. Both issues are easily checked.
 

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LOL. I've let a car sit with ethanol fuel in the tank for five years and it fired right up. People love to blame ethanol fuel for everything. It's a red herring. Not a real issue.
 
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