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Old 07-19-2005, 11:49 AM   #1
PHOENIX
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HELP: Taking Q-Jet Apart

I am still working on this problem.

Carb: Edelbrock Q-Jet 1904
I am having trouble removing the accelerator pump rod ("D") and the choke plate rod ("E").
I want to take apart as little as possible, so I stopped right here.
How do I get these parts ("D" & "E") off so I can remove the top (air horn?).
Do I need to remove "Z" to get the top off?

What is "X" and "Y"?
Do they look normal?
They are caked up pretty well.

Thanks.
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Old 07-19-2005, 12:27 PM   #2
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I used to have a quadrajet that had needle and seat problems. I had to take it apart a lot, usually on the side of the road. . I believe that the accelerator pump rod came off by removing the pin that it pivots on. I used a small nail to drive it out. That is all I remember since it was 15 years ago.

Can you remove "E" by removing the screw that attaches it to the choke?

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Old 07-19-2005, 12:33 PM   #3
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If you really don't want to take it apart, you can push the pin in the picture with just the "D" out and the whole lever will come off.

I usually just pull the top plate off and "twist" it around the choke rod. BUT is that a screw on the end of the rod? Would it remove the rod?

No on "Z", they will pull up with the top, but it is just an lever arm for the rear jets. They are simple to remove.
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Old 07-19-2005, 12:39 PM   #4
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Thanks guys.
I knew if I got the roll pin out of there the accelerator pump rod would come off.
I don't like roll pins so I was going to avoid that. But I guess thats how you do it.
I have roll pin kit, so I am sure I will have a new one that will fit if needed.

If I get the accelerator pump rod off I think I can twist the top around to get the choke rod off.

In a book I have it shows the choke rod as having a clip that holds it on.
Look really easy to remove with that setup.

Ill also look at removing the choke screw and see if that will work.
This should be easier then getting the roll-pin out.
I think if I get one off, I can twist the top around and get the other off easily.
I am just worried about stripping or damaging any of those screw threads, etc.

Thanks!
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Old 07-19-2005, 12:45 PM   #5
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I always push that roll pin in the accelerator pump arm out toward the air horn. I only push it far enough to get the arm out, that leaves a little space between the pin and the air horn to get a screwdriver in there and pry it back into the hole when I reassemble it.

Then lift off the air horn and twist it to get the choke linkage off.
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Old 07-19-2005, 12:49 PM   #6
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Scrubby,
The part that holds the pin on the inside is thicker.
So I could just move it enough like you said and keep the pin in there.
That should be fairly simple.
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Old 07-19-2005, 01:23 PM   #7
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Be carefull when you start removing the airhorn so you don't damage the small tubes which are pressed into the air horn assembly.

I also just 'twist' the air horn around to get the linkages off.

X and Y are the main jet well plugs, after you remove the base plate of the carb you will find two more between the primaries and secondaries (total of 4) which are the secondary jet wells (even though the secondary jets are pressed into the carb). This is a common place for q-jets to develop leaks, you may consider using some JB Weld or other epoxy to seal these up after you clean the carb (Google for hints on how to do this).

Good luck!
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Old 07-20-2005, 08:46 AM   #8
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Remove the screw that holds the choke lever to the choke shaft; the lever pops right off and then it can be separated from the rod. Then reattach the lever to the shaft so you don't lose it or the screw.

Remove the secondary rod hanger and rods. They'll be easy enough to reinstall once the airhorn's back on and with them out of the way it's less to try to align during reassembly.

Since this is an Edelbrock carb and a fairly new casting I doubt the well plugs leak (that problem was much more common on the early Q-Jets) but if you want to seal them with JB Weld it won't hurt.

I'm always happy to provide a home for unwanted Q-Jets...

Brad
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Old 07-20-2005, 12:04 PM   #9
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First off let me thank everyone for their help and tips, I really appreciate it.

Brad,
I couldn't agree more that the secondary hanger and rods should be removed, makes assembly much easier. I need a smaller torx bit to get it out though.

I had to remove the choke screw and tap the accelerator pump pin in to get the air horn off. Maybe if I was able to remove the secondary hanger and rods, I could have twisted the accelerator pump arm off. Either way it went really smooth and easy.
Should I replace the air horn gasket?

The needle pull pin wasn't installed.
I do not know if it fell off when I removed the float or if it was off before.
The needle pull pin (small bent looking spring) was laying next to the needle.
If it had fell off before wouldn't the fuel have moved it around?
The float seems fine. It is the foam/plastic looking type.
There is a small hole in the top of the float, but the float appears to be solid.
I got a little cup, filled it with gas, and rigged up something to hold the float under the fuel. It floated for hours. I dont know if the gas was evaporating or if the float was sucking it up. But the float didn't gain any weight (that I could tell) and it was not sinking. I left it overnight and when I woke up the gas was almost gone so of course the float was sitting on the bottom, not enough gas to float.
Should I replace the float anyway?

So I am guessing the problem is probably heat related, gas getting to hot.
Can fuel pressure verify if this is the problem?
I have access to a laser heat reader thingy, can I use this to see if the fuel line is getting to hot?

I will probably try the "cool can" idea to see if it helps.
Its kind of wierd though, the problem doesn't seem to happen all the time.
I want to get this fixed, I hate breaking down, and I hate tow truck fees.
I have never heard of fuel overflowing because it was getting to hot. Is this possible?
I plan to wrap the fuel lines on the passenger side with something to reflect the heat from the header.
Do you think the rubber line from the pump to the carb can be getting to hot also?
It runs behind the air pump and alternator. It is a pretty tight fit between the brackets and block. The hose is in constant contact with one or the other.
If I feel the rubber line right before the carb is doesn't feel warm at all.

Is it possible my fuel pump (mechanical) is pumping too much fuel?

Any other ideas?
Problem:
after running for a little while truck will die. Doesn't want to start. Fuel overflows from top of carb. Problem has only happened in the heat, afternoon. I only drive the truck to and from work. In the morning never a problem. At lunch its sometimes rough, when it died and I got it towed it was lunch time and hot as hell. The week before it was running rough on the drive home from work, also hot as hell. The problem has gotten worse, the weather has also gotten hotter. First summer with headers too.
I hate getting rides to and from work.
My ride(s) don't seem to mind, but if it goes on for too much longer Ill feel bad.
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Old 07-20-2005, 02:35 PM   #10
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It's fairly easy to rip apart you probably have it apart already now. The bottem plugs on the base plate you need to epoxy they are casting plugs and leak over time. Nappa/Carquest use to have good kits with epoxy in heart shaped plugs to cover the casting plug. You will need a gasket kit and they will have to be exactly the same gaskets to work right. As far as the float the last edelcrap q-jet I worked on had a brass float. I wouldent bother replacing it since the symptoms in your other post arent float related.


Edit: If you are concerned about vapor lock, replace your gascap if it's old and if that doesent help install an electric fuel pump inline. Fuel under pressure cant vapor lock. as far as too much PSI I doubt it, the stock needle and seat assemble can take 8 PSI without blowing even more.
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Old 07-21-2005, 10:29 AM   #11
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Quote:
Originally Posted by PHOENIX
I couldn't agree more that the secondary hanger and rods should be removed, makes assembly much easier. I need a smaller torx bit to get it out though.
An excuse to buy more tools! Always a good thing!

Quote:
Should I replace the air horn gasket?
If it's still flexible and didn't get damaged during removal it's OK to reuse. In the past I've painted them with light oil or soaked them in gas prior to reinstallation if I felt they needed to be "puffed up" a bit, but I can't say if it really made a difference.

Quote:
The needle pull pin wasn't installed.
I do not know if it fell off when I removed the float or if it was off before.
The needle pull pin (small bent looking spring) was laying next to the needle.
If it had fell off before wouldn't the fuel have moved it around?
The fuel inlet does a pretty good job of keeping the inlet needle in place so it's not really an issue; in fact, an incorrectly installed retainer can hinder needle operation. But as long as you're in there you might as well put it back in place.

Quote:
The float seems fine. It is the foam/plastic looking type.
There is a small hole in the top of the float, but the float appears to be solid.
If the hole looks like damage or otherwise not part of the manufacturing process I'd replace it.

Quote:
Is it possible my fuel pump (mechanical) is pumping too much fuel?
Does the pump have a return port as well as inlet and outlet ports?

Brad
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