Stalls when pressing gas too fast

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DoubleDingo

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To filter the fuel. If it is open no fuel is filtered.
 

Nonstop

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It is a check valve. Install it toward the nut/fuel inlet into the carb.
 

thecantaloupeman

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To filter the fuel. If it is open no fuel is filtered.
Oh so I am supposed to take that off the old filter and put it on the new one? Should I take that paper gasket off then? The old one didn't have that.

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DoubleDingo

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It's supposed to come with one, or one end is closed by design. Meaning one end open, the other is metal. Have seen both, metal and the rubber gasket on the downstream end. But it can't be open on the downstream end
 

thecantaloupeman

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It's supposed to come with one, or one end is closed by design. Meaning one end open, the other is metal. Have seen both, metal and the rubber gasket on the downstream end. But it can't be open on the downstream end
Well the side that goes against the spring is closed (metal) and the other open with a gasket. My old one is the same but instead of the paper gasket its got that rubber thing that sticks inside the filter with a spring inside it, and also acts as a gasket. Its weird that the new one didnt have one. The one I got that was the wrong length came with one. Maybe its just not meant for this carb, or maybe its just a different design and still works.
 

thecantaloupeman

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Start with the fuel filter, then check the accelerator pump. Look down the throat with the engine off. Open the throttle using the arm and look for 2 strong streams of gas (one from each side).

Also check for any vacuum leaks. All these are relatively easy starting places.
Will the streams be pretty obvious? If I don't see them what does it mean? Is fixing an accelerator pump an easy task?
 

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Streams are pretty obvious - like two little men pissing down the carb primaries.

If it is the accelerator pump, with all due respect, easiest will be to have a shop replace the pump, or have them rebuild the carb. There are a lot of small parts in a carburetor.
 

DBarre

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Well the side that goes against the spring is closed (metal) and the other open with a gasket. My old one is the same but instead of the paper gasket its got that rubber thing that sticks inside the filter with a spring inside it, and also acts as a gasket. Its weird that the new one didnt have one. The one I got that was the wrong length came with one. Maybe its just not meant for this carb, or maybe its just a different design and still works.

The new replacement filter is probably just made cheaper with the paper gasket. You should probably watch some youtube videos about carburetors to understand how they work. It could help you diagnose any issues you may be having. Then, if you have more questions, you can better describe the issue. I've started watching Uncle Tony's Garage and, even though he's a Mopar guy, he really knows his stuff.
 

bucket

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Why are you guys making so much fun?
I mean come on, we all had to start somewhere.

Yep. When I was younger and learning, all I had was dad to show me some things, or I figured it out myself. Lots of trial and error. I bet if I would have had internet forums, I'd a asked a bunch of questions too. Or at least googled all kinds of crap.
 

thecantaloupeman

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Streams are pretty obvious - like two little men pissing down the carb primaries.

If it is the accelerator pump, with all due respect, easiest will be to have a shop replace the pump, or have them rebuild the carb. There are a lot of small parts in a carburetor.
Actually I don't think I've mentioned that the carb was rebuilt right before I got the truck. Is it likely he messed it up?
 

thecantaloupeman

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Yep. When I was younger and learning, all I had was dad to show me some things, or I figured it out myself. Lots of trial and error. I bet if I would have had internet forums, I'd a asked a bunch of questions too. Or at least googled all kinds of crap.
Thank you! My Dad has no idea how to work on cars or even use power tools. I really just need a source to ask questions, because I don't know anyone yet who can mentor me. It's nice to have this even though I may be overusing it a bit. If I had a lot of money and maybe another car, I'd be fine with messing around until I figured it out, but I don't. If I screw something up, I could be out a lot of money and possibly my car If I break it beyond something I can fix or pay to get fixed.
 

thecantaloupeman

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The new replacement filter is probably just made cheaper with the paper gasket. You should probably watch some youtube videos about carburetors to understand how they work. It could help you diagnose any issues you may be having. Then, if you have more questions, you can better describe the issue. I've started watching Uncle Tony's Garage and, even though he's a Mopar guy, he really knows his stuff.
I checked out that Uncle Tony guy and watched his video on carbs. He really does know his stuff. He didn't have a script or anything, just talked for a half hour about how carbs worked like he was a college professor. Pretty awesome! Thanks for the recommendation.

I put that other duralast filter in and it didn't seem to solve my problem. Just for giggles I went to NAPA and I asked what the rubber thing was. He said it was called a restrictor. Apparently it's just an added feature, but they had a filter for my truck in stock with a restrictor and it was 4 bucks so I'm gonna just use that one. It is much more similar to the old filter that came out of the carb.

I'm sorta curious though why my truck uses the short filter. Most videos of people with the 5.7L have the long filter. When I put that into the auto parts store computer it says I need the long one. My carb obviously wont fit the long filter so maybe it isn't original to the engine. It got me thinking maybe it's taken off another vehicle and that's why the owner claimed it was "rebuilt".

If it isn't rebuilt that could explain why my accelerator pump could be an issue. I still have to go check that, but it seems likely after some research that my symptoms match the accelerator pump failure.
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Craig 85

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To make sure you are getting the correct parts for your carburetor, there should be numbers stamped on the driver's side rear corner. He's mine. Your's should have 8 digits for a '78 and start with 1705****

http://www.carburetion.com/quadnumber.htm

#17084502 - Breakdown
1708 - 80's
4 - Production year - 1984
5 - Quadrajet (4 bbl) California standards
0 - Chevrolet
2 - Even - Auto trans
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