Question about Chevrolet Silverado

1 Answer

I have a 1978 Chevy longbed with a 350 engine, dual tank. I have a new fuel sending unit, spark plugs, rebuilt carter quadrajet, new fuel pump, new spark plug wires, new distributor rotor. During acceleration, it bogs down and doesnt go any faster while other times the engine hesitates repetively then after the hesitating, it will accelerate normal. What can be the cause?

Posted by on

  • yadayada
    yadayada Mar 21, 2011

    Is the fuel pressure 5-7 PSI??

×

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Chevrolet Master
  • 2,002 Answers

The problem is in your carburator. Was it rebuilt in a shop or by yourself or a friend?Did they know what it was going on? It could be that the float level is too low. It could be that you have the plunger rod for the power valve in the wrong hole. It could be that you just need to adjust the mixture screws on the front. I would start with the mixture screws. Turn them in until they seat but don't force them,be gentle. Turn them out 1 and 1/4 turns each and start from there. You will have to turn each one separately from here.Set your curb idle about 500 RPM and turn 1 screw out until you hear the idle start to go up and then back it off until it starts to falter or miss, them come ahead just enough to bring the engine out of that. Then do the same with the other screw. Reset your idle and rev the engine by hand, a couple of cracks and then crack the 4 barrels open and let go. If it stalls then open the idle screws about 1/8 turn and try again. When the engine will return to idle off the 4 barrels without stalling your mixture screws are set right. Make sure you keep resetting the curb idle, usually 500RPM for a standard and 750 RPM for an automatic.
If you rebuilt the carb yourself then look on the rebuild sheet that came with the kit for your engine application and make sure you have the power rod in the right hole and that you have the correct float level. Different applications have different float levels even with the same size engine. Set them for the engine you have it on, if the carb came off something else. Hope this helps.

Posted on Mar 21, 2011

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

I need to know what size of carburetor i need for a 1978 chevy with a 350 engine?


This is a complicated question. It depends on how you plan to drive the car.
A 500 cfm Holley would probably be more than enough unless you are using the car on a track.
300 cfm can probably work but may not give you much more performance than a stock Quadrajet.
Holley is the best for modifying a carb to a specific engine. You can pick the jets and other parts to your needs.
Quadrajet was stock on GM.

Jul 02, 2012 | Cars & Trucks

1 Answer

I have a 2000 gmc 3500hd,the fuel gauge stopped at half way and i run out of fuel. the rear tank is not sending fuel to the front tank?


David Johnson is wrong about that. The Chevy HD dual tank has two sending units, one in each tank , one fuel pump, a fuel pump relay switch and a equalizing pump. If the truck stalls out at 1/2 tank, it is the equalizing pump. That pump, pumps fuel from the rear tank to the front. If the pump is out, the front tank empties, the truck shuts down, the guage reads half tank because the back tank is still full, but the equalizing pump won't pump the rear fuel tank load to the front. Hence the problem you listed above, not a sending unit.

Dec 15, 2011 | Cars & Trucks

1 Answer

Best replacement carb for 1980 vette , simple is the key word


Best simple replacement carb for your Vette would be to have the stock Quadrajet rebuilt by an ols pro...when built right these carbs of 780 cfm are powerful and reliably consistent...be sure to keep the electric choke...A bolt on replacement that I have used is the Carter Thermoquad...while this carb permits easy adjustments, the secondaries are not as large as the Quadrajet...therfore the kick down response is not as powerful as the Q-jet...Yes, the primaries are larger but the 625 CFM again limits the response on your LT-1 350...Hope this helps.

Mar 24, 2011 | 1980 Chevrolet Corvette

1 Answer

Replace a fuel pump on a 1996 cevrolet S-10 4 cylinder


the fuel pump is located inside the fuel tank.

  • Park your Chevy S10 in a safe place with a level surface. Make sure you have enough room to work around the truck.
  • 2 Unplug the fuel pump relay, which is located in the fuse/relay box in the engine compartment on 1995 to 1997 2.2L engine models. Markings on the relay or the back of the fuse box lid should identify the relay. On other models, press the small stem inside the Schrader valve--similar to a bicycle-tire valve--located on the fuel inline rail, right before the first fuel injector. Cover the valve with a shop rag as you depress the stem with a small screwdriver to catch the squirt of fuel.
  • 3 Disconnect the black, negative battery cable and raise the rear of the truck with a floor jack. Safely support it on two jack stands.
  • 4 Drain the fuel tank into an approved container through the filler pipe. Use a hand siphon pump if necessary.
  • 5 Disconnect the clamp from the filler hose at the tank with a screwdriver and remove the hose. Remove the tank shield. Support the fuel tank with a floor jack and a piece of wood on the jack pad to avoid damage to the tank.
  • 6 Remove the tank-holding straps with a ratchet and socket.
  • 7 Lower the fuel tank so you can disconnect the fuel lines from the fuel pump/sending unit assembly on top of the tank. Unplug the pump electrical connector and lower the tank to the floor.
  • 8 Turn the lock-ring tabs holding the pump/sending unit assembly to the tank counterclockwise with a drift punch and a soft hammer until the ring is released.
  • 9 Lift the pump/sending unit assembly off the tank, remove the pump and install the new pump in the pump/sending unit assembly. Discard the pump/sending unit O-ring seal.
  • 10 Install a new pump/sending unit O-ring and set the pump assembly in the tank.
  • 11 Lock the assembly lock ring by turning the ring clockwise until it locks in place.
  • 12 Connect the fuel lines to the to the fuel/sending unit assembly and plug the pump electrical connector.
  • 13 Raise the tank to its mounting position and install the tank-holding straps. Install the tank shield and connect the filler neck to the tank.
  • 14 Lower the truck, plug the fuel-pump relay and connect the black, negative battery cable.
  • 15 Refill the fuel tank, start the engine and check for leaks.
  • Sep 11, 2010 | 1997 Chevrolet S-10 Pickup

    2 Answers

    I need to know what kind of fuel pump to get for a 1989 chevy caprice


    here is the part number for the fuel pump kit from Carter, everyone carries Carter.
    CARTER Part # P74000 {In Tank Fuel Pump}Includes Wiring Harness $38.79

    May 21, 2010 | 1989 Chevrolet Caprice

    1 Answer

    I am trying to start my 1980 gm 350 in my boat. engine will turn and have new fuel and filters. Pulled off coil wire and got spark, grounded a spark plug to the manifold and got spark. What could it be?...


    definitely a fuel issue. be sure to check that the distributor isnt 180 degrees off. you say it'll start when you pour some fuel into the carb, it sounds like you arent getting enough fuel then. try adjusting the float level higher so that more fuel will be pumped through. and how old is the carb? has it been rebuilt recently? make sure the jets are clean and adjusted properly. make sure none of the mixture screws are bottomed out. it sounds like it's all the quadrajet's fault on this one!

    Feb 16, 2010 | 1983 Chevrolet K1500

    3 Answers

    1979 chevy step van 350 new fuel pump rebuilt carburetor wont sta


    remove the fuel line from the carb, put it into a bottle, crank the engine, If the bottle has fuel in it the fuel pump is working properly, if not, check the filter, and the fuel lines to the tank!!!

    Nov 02, 2009 | 1979 Chevrolet C/K 3500

    1 Answer

    Hesitates when going 55mph


    How does it perform acceleration wise up to 55 mph? If good, then I'd have exhaust checked for restriction as well, as in plugged catalytic converter.

    Jul 18, 2009 | 1978 Chevrolet Caprice

    1 Answer

    87 chevy truck with TBI idles too fast


    Spray the intake with carb cleaner to find the vacuum leak. Check where the EGR mounts and the throttle body gasket sense you had both off.

    May 10, 2009 | 1987 Chevrolet R20

    Not finding what you are looking for?
    Cars & Trucks Logo

    Related Topics:

    222 people viewed this question

    Ask a Question

    Usually answered in minutes!

    Top Chevrolet Experts

    yadayada
    yadayada

    Level 3 Expert

    75822 Answers

    Colin Stickland
    Colin Stickland

    Level 3 Expert

    22156 Answers

    Jeff Turcotte
    Jeff Turcotte

    Level 3 Expert

    8210 Answers

    Are you a Chevrolet Expert? Answer questions, earn points and help others

    Answer questions

    Manuals & User Guides

    Loading...