Did you get a standard steel or stainless fuel line? I had a hell of a time with stainless, and would never buy that again. I made it work by bending the line to make sure the fittings were square to the line before screwing them in, but it was not easy.

 

Thanks for your response Bikespace! I used the standard line. I think I am going to have to do the same and bend it a little to make it square so it fits in perfectly. The preformed line almost fit perfectly. After testing it out and taking it back apart to tighten it I spend almost an hour just trying to get it to thread to the new fitting. Frustrating!! I am going to bend it and square it up.

 

Sounds like you should have it a bit easier than I did! The compression fittings have to be perfectly squared up to engage the threads. You can press the compression flare of the line against the bottom of the fitting, and you'll know everything is aligned when the nut on the line threads in easily. At least in theory.

Good luck, and post some pics! You are almost there.

 

You might want to disconnect or loosen up the line at the top then when off, thread the bottom end into the fuel pump by hand, then go back to the top fitting. It's a lot easier than trying to bend or maneuver the line at the pump.

 

Fuel pump is on and all lines are hooked up. Thank you for your advice!!

I turned the engine over and no leaks so all is good! To get the car running though I had to pump the pedal multiple times and then hold it down about halfway for the engine to catch. This is normal right? I assume it is because they are new fuel line and rubber lines to the pump. Next, after the car was running I let it idle for about 5 mins in the garage and everything looked great. It idled great in my garage so I figured I would take it for a spin around the neighborhood to make sure everything is all set.

First, it seemed as if I gained 50 HP! Could that be because of the new pump? The amount of power and the car felt so different! All was going well until maybe 1/4 mile up the road then...

There was a UPS driver on one side of the street and a car parked on the other so I had to stop. After letting off the gas, the car was fine for a second and then it just stalled out. I could not figure out the problem. I was on the road, so I pulled off the air cleaner and tried firing it up but it wouldn't catch. So I pushed it back and put it in neutral and coasted home. There was a flat spot on the street before I got home where I tried to fire it up and it fired right up but then would die out so I had to coast the rest of the way home. I was thinking a clogged fuel filter but I changed that when I first put on the fuel pump. I was also thinking clogged air cleaner filter? Need some advice!! Thoughts?

 

Have you looked at the pickup inside the tank? It could be the sock on it is clogged up.

 

No, that's not normal. On a cold engine, you should pump the gas twice to set the choke and fast idle, then crank the engine and it should start with no intervention. Can you post some photos of your overall engine and of your carb? Perhaps your fast idle cam isn't connected.

As @Sigforty suggested, take a look at the pickup sock in the tank. If you pump the gas now, does it squirt out inside the carb? It should if the bowls are filled and the accelerator pumps are working. Was the engine warm or still cold when it stalled?

 

Great! Thank you. So before the fuel pump issue I would pump the gas two-three times and crank the car and it would start right up just as you said. When I pump the gas now and move the throttle linkage gas shoots in the carb like all is normal.

I have a stock 79 l82 4 speed and quadrajet carb. I had the carb rebuilt last summer at a very reputable carb shop. It ran perfect for a whole year until the fuel pump issue. I would say the engine was warm because I let it idle for about 5-10 mins and it was warm out today.

 

Some shots of my carb...

I tried firing it up again this a.m. and it would not catch unless I had a wide open throttle. After it caught it would run rough and smelt like a ton of gas and gas smell from the exhaust. Felt like it was flooding substantially. I had the carb rebuilt last year and ran great until after winter storage and the fuel pump issue. What could cause the excessive gas getting in the carb? New fuel pump with more pressure than the failing old one? Can an old fuel pump cause carb problems? I strongly feel like it's related to the fuel pump because I didn't have an issue all last year. Thanks!

 

I would strongly suspect that the needle and seat in your carburetor have gotten gummed up over the winter from the ethanol gas causing the flooding. It's best to make your last fill up before winter storage using non-ethanol gas. A crude but possible solution might be to pour or squirt some carburetor cleaner down the bowl vent tube and let it sit over night or longer. Short of that your carburetor will need another overhaul. I don't believe the new fuel pump is the issue.

 

What @Roy W. said sounds correct. As long as it was the correct fuel pump, it shouldn't be at fault. It could be putting out too much pressure if the return line were blocked, though.

At this point, I'd strongly encourage you to contact @lars and ask for his Q-Jet papers (and his timing papers, too, they're awesome). For the hard start, it could be something simple, like a choke and fast idle adjustment (the choke looks too closed in the photos, but I'm no expert). But it sounds like the bowls are overfilling. His email is all over the forum, PM me if you can't find it.

 

That's a real shame what the "reputable shop" did to your carb. Nobody reputable or knowledgeable about carbs sandblasts all the original finishes off the carb and destroys the carb like that... Those people should be shot.

But if it was running OK before, chances are high that you simply have a piece of crud in the needle/seat assembly, or that the float has gotten jammed down into the bottom of the float bowl and is stuck. You'll need to pop the airhorn off the carb, remove the power piston & rod assembly, remove the phenolic filler, remove the float, and remove the needle/seat. You'll then need to blow the carb out real good by blowing through the inlet filter and out the seat hole. Then, blow out the seat real well, clean the needle, and re-assemble it, checking the float level and checking the float for any binding (make sure they installed the right float in the carb - many "reputable rebuilders" install the 4MV float or a brass float, and these will jam and bind in the M4M float bowl). Make darned sure you have the power piston correctly installed with the rods inserted in the jets before you re-install the airhorn.

My airhorn removal & installation instructions as follows:

Technical Procedure #1: How to remove the Airhorn (the “Top”) off of a Q-Jet

To pop the top off a Q-Jet, proceed as follows:

1. Remove the air cleaner stud.

2. Using a hammer and a small pin punch or a small finish nail, tap the roll pin holding the accelerator pump lever to the top of the carb in towards the choke horn wall. Don't tap the roll pin all the way up against the wall - leave just a slight gap so you can later get a screwdriver blade in behind it to pry it back again. Remove the accel pump lever.

3. Remove the single screw holding the secondary rod hanger to the top of the carb and remove the hanger with the secondary rods.

4. Remove the choke connecting rod. There are 2 types: One type has a clip holding it to the choke lever. Remove the clip, disengage the rod from the upper lever, then twist/rotate the rod to disengage it from the lower lever inside the carb. Later model carbs have a single screw holding the upper lever to the choke shaft. On this type, remove the screw, remove the lever, and remove the choke rod by twisting/rotating it to release it from the lower lever inside the carb.

5. Remove the (2) 1/2" head bolts at the front of the carb.

6. Remove the 9 top attach screws: Two long screws in the very back; a screw on either side of the secondary airvalves; two screws just forward of the secondary airvalves; two screws just inside the choke air horn right at each primary discharge nozzle, and a single screw center front. If the carb has the stock screws in it, the two screws inside the air horn are designed to be too big to drop down into the intake manifold. But many aftermarket screws can, in fact, drop through the carb and go into the intake. Once you have loosened these two screws, use a pair of needle nosed pliers to carefully lift them out and make sure they don't drop.

7. Lift the top of the carb straight up until it clears the accelerator pump and until the air bleed tubes clear the gasket. If you have a pre-’75 Q-Jet with a choke-pulloff attached to the float bowl of the carb, **** the top over to the side to disengage the secondary airvalve rod.

8. Remove the gasket by carefully freeing it from the power piston/primary metering rod hanger.

9. Remove the accelerator pump.

10. Remove the power piston/primary metering rod hanger by pushing it down against its spring pressure and "flicking" it off your fingernail so it pops up. A couple of flicks will disengage the locking collar from the casting, and the assembly can be removed.

11. Remove the phenolic float bowl filler.

12. Remove the float and needle as an assembly.

13. Remove the main jets.

14. If you’re removing the needle seat, use a very wide flat-bladed screwdriver so you don’t screw up the screw slot in the seat. Note that there is a small round gasket under the seat – it is often stuck to the float bowl.


The rods and the jets are stamped with their sizes, but you may have to clean them and use a magnifying glass to see the stampings. Some commercially rebuild carbs use “generic” jets and rods with no size markings.


Only trick for re-assembly:

1. When installing the power piston, take care to fish around until the rods drop down into the jets and the power piston works smoothly. Gently push the piston nylon locking collar back into the carb casting. I've seen people not get the rods into the jets, and simply smash the top of the carb down onto the piston/rod assembly. Obviously, this will bend and destroy the rods.

Once you have the top back on, installing the choke linkage rod is considered the only "tricky" part. There is a short lever arm down inside the carb, and this arm has a hole in its end. This arm is very easy to see when you have the top off the carb, so I recommend that novices take a look at it and its orientation/function while they have the top off the carb. With the top off, take the choke rod and practice installing/engaging it in this lower lever until you get the knack of rotating the rod slightly to engage it in the hole in the lever.

Once you have the top back on (taking care not to overtighten screws and bolts), activate the choke linkage on the outside of the carb to move this lever arm to its furthest "up" position. You can just barely see it if you look down the carb. Now, insert the choke rod down into the carb, with the rod rotated slightly. Engage the hole in the lever arm at this angle, and once you've hooked the arm, rotate the rod to fully engage it.

Install the accelerator pump lever to the top of the carb. Insert a finish nail or a small pin punch through the roll pin hole to assure that it's aligned, and then use a small screwdriver to pry the roll pin back through the lever.

Install the secondary metering rods with the hanger.

 

Do you know what psi your fuel pump is putting out? If its above 7 psi, you could just be blowing past the needle and seat. Quadrajets like it low between 4 and 6 psi. It could also be all or some of whats been suggested..... Your float could have failed or is stuck, your needles are stuck, theres varnish from bad fuel or just plain crud. You could pull the coil wire and have someone crank it over and see if fuel is just running out of the fuel ports. if so then its probably one of the above issues. Once the cranking stops, if its still coming out you have something stuck. If it stops it might be that the pressure is too high.

You should try and put a fuel gauge on it first and see what pressure you have. If its around 6 psi you may have to do as Lars suggests and open her up and see whats up

 

Thankle you for your help. I will have to try the carb cleaner to see if that works. Should I spray it in the carb too? Weird this happened so suddenly it leads me to believe it could be something plugged or not working as it should that makes it have too much gas.

The fuel pump is a mechanical fuel pump from napa. It is identical to the one I took off. The return line is connected so it has the supply, the return, and the fuel line to the carb. All is new. Why do you think it is too closed? Can it just happen randomly where it could work one day then get too closed the next? Something is definitely not working right! Appreciate your continued help!

Lars, thank you so much for reaching out. I appreciate your comments. First, could the new fuel pump push something into the carb to clog it? I changed the fuel filter before I changed the fuel pump. Second, how difficult is it to do the above process? I know you are the man when it comes to carbs... To be completely honest I am not comfortable with carbs at all. I have done mechanical work on the car, plugs, wires, tune up, oil, calipers, pads, put in new side pipes and mechanical fuel pump. How difficult would it be to diagnose this problem? I am not comfortable with it but I am willing to take a shot if it is relatively straight forward. Appreciate your response!

Thank you Rescue Rodgers. Is the above process noted by Lars the same as you are saying like checking the float and needle? Trying to get this new problem solved! Thank you!

 

I don't know what would cause the choke adjustment to change, but it doesn't look right to me. I think there should be a bigger gap at the front edge on a cold engine. I had hard-starting issues when I didn't have the choke set correctly. @lars's Q-Jet setup instructions have the procedure and measurement.

EDIT: Please read @lars's reply below for the correct choke adjustment.

That is the least of your problems, though, but now you have the attention of folks who are much better versed in Q-Jets and able to help. Checking the fuel pressure is a great idea, if you can do it safely. You could rig up a simple T in a spare fuel line, but make sure you switch back to a solid steel line from the pump to the carb for normal operations.

 

Joe -
With the engine off and cold, the choke should, in fact, be fully closed with no gap at all - the photo shows the correct and normal position. You can see that the engine is not running, because the choke pulloff is not retracted. Once the engine starts, and the pulloff retracts, the choke will crack open 1/4", if correctly adjusted.

Lars

 

Thanks Lars!

 

Good time to update! Thank you for your advice and help. I went over Lars papers and took the carb back to get checked out. Then I thought like Lars said in his papers "90% of all carb problems are actually ignition problems". It still would not fire up unless I was giving it lots of gas. Did a pressure test on fuel pump and that checked out.

Next was looking at ignition. Pulled plugs and they were fuel soaked, cleaned them up but still wouldn't fire up. After that I concluded I wasn't getting a strong enough spark so I replaced the ignition control module, rotor, ignition coil, plugs, cleaned up the cap and made sure everything was snug. Then it was time to fire it up. I pumped the gas 3 times and it fired right up! Had to give it a gas maybe like 1/2 in on gas pedal and it fired up like normal!

From there is smoked very badly looked like blueish/black smokeI attributed it to the excess fuel from flooding earlier and it cleared up about 30 seconds. It idled fine, smoke cleared, and drove 20 miles without stalling and I tried to make it stall lol and ran a little rough during the trip but not bad and can see some smoke on acceleration out of tail pipes.

The next day, same thing fired up but smoked alot again during startup (black/blue) for maybe 20-30 seconds. I thought it wouldn't happen since I cleared it out the day before. One thing I noticed is also black spots on the floor one near exhaust tips but they weren't oil i touched it with my hand and it just disappeared (carbon?). After driving another 20 miles it seemed to not smoke on acceleration but still ran a little rough. Still didn't stall but did smoke alot on startup again.

Oil was changed recently and looks fine now, darker but looks normal. Oil pressure was perfect on those 40 miles and temp was perfect as well.

Any advice? Thanks all!

 

Update- went to go for a new ride. Pumped pedal 3 times and car fired right up. Very little smoke on startup this time and did not run rough and idled perfectly. Still a little smoke on strong acceleration but nothing like it was. Drove another 20 miles, I guess I need to just keep clearing it out from before and driving it/running it.