Carb or Fuel delivery problem?

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Jdgrant96

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Got new fuel filter in yesterday, will put it in tomorrow. I am still a new squarebody owner and did not realize that the filter is supposed to have a rubber check valve on it. The one in there at the moment has nothing at all. I am suspecting that is where the rubber bits in the carb bowl possibly came from. If it there is a vacuum leak its definitely significant wherever it is. I'll have to go back and spray to see if I can find anything. I'll also give the gas station a call.
 

Ricko1966

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If there are rubber bits in the bowl, there are probably rubber bits in the metering block, idle jets,transition ports, who knows where.I'm thinking you have a plugged jet or needle and seat

The rubber bits just got me, so my gut says carb. How hard is the top to pull off that carb? If it's like a quadrajet you can't do this. When they act like that when they die I take the top off the carb or look in the site glass or pull the site plugs etc.But I check float level after it died.If I have a float bowl full of fuel, I know delivery is not the issue. You could also do a fluid volume test but I think something's plugged in the carb. Only time I 've had fuel problems it was water,fill a glass 1/2 full ,pull the line at the carb and crank, let it sit 1/2 an hour you"'ll see the fuel seperate if it's got water in it.
 
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75gmck25

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What filter are you replacing?

You should have the carb filter in the inlet, and a larger barrel-shaped filter connected to the metal fuel line coming up from the fuel pump. The large filter can be just one of the metal fuel filters from Autozone with 3/8” fittings on each end, but it acts as a very easily replaceable pre-filter.

Also buy some SAE J30R7 or SAE J30R9 fuel injection hose and use it to replace all the rubber hose in the engine compartment. That hose will hold up against the ethanol in modern fuels. However, its expensive so expect sticker shock.

Bruce
 

Jdgrant96

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Ruled out any vacuum leaks. Top of carb was fairly easy to take off when I did it. Most of the rubber was sitting in the carb bowl and was spotless when I put it back in. Checked it again a few minutes ago and more black bits. I'll pull it off and clean it again tonight. Goal for this weekend is to get the fuel system squared away so it'll be pull the tank, clean it, clean lines, replace sending unit, rubber hoses, new pump and in carb filter. If there is a inline filter I'll do that as well.

I appreciate all the responses so far
 

Jdgrant96

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Tore apart carb. Lots more rubber in there. Have a picture but won’t upload from my phone.
 

AuroraGirl

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my filter is filled with rubber bits, i suspect from the fuel lines from pump and the pump itself. my filter is before my carb and it does catch them. so im gonna replace fuel pump and rubber lines and blow some compressed air and maybe with the old rubber lines some solvent through. let itdry, air hit the hard lines, then put new rubber on. of course with a no pump to boot.
 

gotyourgoat

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Tore apart carb. Lots more rubber in there. Have a picture but won’t upload from my phone.
I want to know more and I need to see these pictures.
Posting pics here is quite simple really. Select (from the post reply box) upload a file, Hit browse, and select where and what you want it to come from. Select and go.
Sometimes different phones have hiccups though.

Send them to me and I'll post them if you have troubles. No worries. ;)
 

AuroraGirl

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I want to know more and I need to see these pictures.
Posting pics here is quite simple really. Select (from the post reply box) upload a file, Hit browse, and select where and what you want it to come from. Select and go.
Sometimes different phones have hiccups though.

Send them to me and I'll post them if you have troubles. No worries. ;)
You must be registered for see images attach
 

Jdgrant96

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Oh now it works lol. All the black stuff is rubber looking bits

You must be registered for see images attach
 

Jdgrant96

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All seals, rubber, gaskets in carb look fine still. Cleaned it out as much as I could and believe all the circuits are good to go. Gas looks fine, had some small debris in it but not as much as I expected. Pump seemed to be pumping ok, 8 seconds to fill a bottle. I’m very curious to get the tank off this weekend and find the source of the rubber.
 

gotyourgoat

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First thought was bits of disintegrated rubber fuel line. Those bits look way too big to be getting through the carb inlet filter though. Unless the wrong one was in it?

There are different sized carb filters. A long and a short but I don't remember which quadrajet got which.
 

Jdgrant96

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The verajet had the 2 inch filter in it so I got the same replacement. This one actually has a rubber seal though. I know they have two different for the quad jet but was it the same for verajet?
 

gotyourgoat

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I want to say yes but don't know for certain.
That looks like way too much material to be the rubber seal from the old filter. What did the old filter look like?
 

Jdgrant96

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Definitely too much rubber, this is the second time I’ve cleaned that much out. Old filter had no seal, just a VERY thin gasket. Filter itself had no significant debris inside.
 

Jdgrant96

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New pump, rubber lines, sender and filter are in, cleaned the tank as well. Running just fine now. I guess all that trash from the tank was clogging it all up.
 

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