Cars & Trucks Logo

Related Topics:

Anonymous Posted on Jan 03, 2013

I have a 1985 gmc Sierra with an 305 with an edelbrock 1401 500cfm carb how should I adjust the carb to run stronger with the 2 screws on the front of the carb

1 Answer

Bill Lindsey

Level 2:

An expert who has achieved level 2 by getting 100 points

MVP:

An expert that got 5 achievements.

New Friend:

An expert that has 1 follower.

Hot-Shot:

An expert who has answered 20 questions.

  • Expert 34 Answers
  • Posted on Jan 03, 2013
Bill Lindsey
Expert
Level 2:

An expert who has achieved level 2 by getting 100 points

MVP:

An expert that got 5 achievements.

New Friend:

An expert that has 1 follower.

Hot-Shot:

An expert who has answered 20 questions.

Joined: Jan 01, 2013
Answers
34
Questions
1
Helped
8161
Points
106

Start by checking the existing settings of your air adjusting screws (the two in front). you do that by turning the screws one at a time in (clock wise) at one half turn at a time until they stop. should be appx. 1 1/2 turns. Be sure to jot down how many turns it took so you can put them back if need be. Now set both at 1 1/2 turns out (counter clock wise) NOTE. Do all this with engine off...... Now start engine and turn screws out slowly one at a time about 1/2 turn then in until you hear the engines RPMs start to drop then turn out again 1/4 turn. Now your air/fuel mixture should be as close as your going to get it without a dino machine

5 Related Answers

Anonymous

  • 24 Answers
  • Posted on Jan 10, 2009

SOURCE: i need 2 know what size speakers go in the front doors

6 1/2" seperates

Ad

Anonymous

  • 1118 Answers
  • Posted on Feb 26, 2009

SOURCE: 1985 gmc sierra shakes

Sounds to me to be a timming issue like maybe retarted, also chk. to see if the wire is pluged in by dist, the wire that you have to unplug when your going to time it, i can't remember what its called. There is only 2 things on this truck thats controled by the computer is spark and fuel, if that wire is unpluged by dist. it will run like that, unless someone has changed it back to the old style dist. and carb. if thats the case loosen dist. and move it a little and see if it dosent run better, clockwise advance, counter clockwise is retarded.

dennymulford

Dennis Mulford

  • 1055 Answers
  • Posted on Apr 20, 2009

SOURCE: 1998 GMC Sierra (C1500) 5.0L 305 V8-right rear brake line

i dont know of any recall for that
and yes it can be replaced without removing the bedeasy wasy too do it is go too auto zone and buy a roll of brake line and run it along side of the old one and just leave the old one in the hangers and use tie straps too hang the new one!!!

joecoolvette

joecoolvette

  • 5660 Answers
  • Posted on Sep 02, 2009

SOURCE: smoking 305 motor

Time to rebuild the engine. Your piston rings, main bearings, connecting rod bearings, camshaft bearings, and valve guides in the cylinder heads, are worn out. Possibly the shafts are worn on the valves, and the piston skirts also. (Means new valves, and pistons, plus boring and honing the block. You'll need a new oil pump, gaskets, freeze plugs, spark plugs, oil and filter, for a few more things to add to the list)

What you are seeing is called 'Blowby'. This is a normal thing with a worn out engine.
Also replace the PCV valve as it is probably clogged up. (Positive Crankcase Ventilation Valve)

daves944

Dave C

  • 1050 Answers
  • Posted on Jan 29, 2010

SOURCE: my 1985 chevy 305 gets 4mi to the gallon

Check your ignition timing at 3500 rpm you should have about 40 degrees of advance If not, something is sticking in the distributor, either the vacuum or mechanical advance. This will cause a big reduction in fuel economy. Also, check your tire pressure. The cfm on a rochester is really not important. The primary bores are so small and they are the only thing allowing the mixture in most of the time.

Ad

Add Your Answer

×

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

0helpful
1answer

Hi I just want to how much easier is it to tune an edelbrock carb then a quadrajet carb

Edelbrock cars are square bore and Quadrajets are spreadbore make sure you have either an adaptor plate if running stock manifold or you'll have vacuum leaks, as far as tuning Edelbrocks are EZ. 2 air/fuels screws that only effect idle, turn in till runs rough then back out 1/4 to 1/2 turn on both, that will set it for economy, for performance engines, turn out or counter clockwise till runs rough then turn back in clockwise 1/2 to full turn, set idle ***** and your good to go, the two vacuum ports in front are distributor advance, the right side closest to manifold is full time vacuum hook there for performance or left side for economy.. if you buy a new edelbrock carb it will run great right out of the box, also has a set/up DVD, for novice Mechanics, ez to change metering rods too, hope this helps, and in my opinion Quadrapuke carbs are junk.
26158435-1ng1ie4xxcdrqgg13cdx01r4-3-0.jpg
0helpful
1answer

How to adjust a carburetor

this sounds more like you need the carb rebuilt to clean out all the dirt in the small passages and replace the needle and seat as well as the float. the idle air mixture screw are at the front of the carb at the base one for each barrel the carb has. this year should have tamper proof plugs covering the mixture screws which the carb will have to come off to remove them.
0helpful
1answer

I own a 1977 GMC Sierra C25 with a 5.0L V8 305 cu in. I would like to know what each of the two screws on the front of my carburetor are.

Down low at the base near the intake manifold are two slender pointed air/fuel mixture screws with springs on them. While running at idle, Turn them in until it starves and almost dies at idle then back out 1/4 turn. Usually out from closed stop about 1 1/2 turns.
0helpful
1answer

1985 chevy c20 vacuum problems

on this truck the vacuum is pretty basic, im guessing you have a 305 (5.0) or a 350 (5.7), on the front of the engine compartment near the fan shroud somewhere (if it is still intact) you should have a diagram of all the vac lines
you probably have a quadrajet carb, if you are mechanical and patient they are not hard to rebuild

blowing out the carb with carb and choke cleaner isnt a bad idea either, have someone keep it running and slowly run like 1/4 to 1/2 a can down the carb spraying all around
1helpful
1answer

I need to adjust my qcarb on 1985 gmc-pickup two wheel drive . i need to know what evey screw does

this truck doesnt have a carb, this has a throttle body, its fuel injected,there are no adjustments,every adjustment is done from the factory, the computer controls the idle,trying to raise the idle will throw the tps readings off,
0helpful
1answer

Should I rebuild my Ford Bronco 351 Windsor Holly 4 bbl carb or replace it with an Edelbrock carb?

In all my experience, if you know how to correctly tune a edelbrock then go with that, but, holley has outstanding carbs that can muster up to an output of 1,200hp. it would be much cheaper to et a rebuild kit from say, o'reillys, 20-45 dollars depending on which one you have.
I have a 1985 Bronco 351w 4x4, i just rebuilt my holley and she runs smooth
0helpful
1answer

1979 sierra grande runs too righ even after adjusting carb

You may have an internal carb gasket leak or your floats may be adjusted too high.After you run the truck look into the carb to see if there is gas still dripping into the carb bore.Also after running with engine on remove the front fuel level check screw. (have lots of rags under to catch fuel) Fuel level should be right below hole.If it is spilling out it is too high.Floats need to be adjusted up for fuel level to go down.
0helpful
1answer

Popping Noise from unburned fuel in carb - 600 edelbrock manual

try a smaller more factory carb.and see if it helps
0helpful
1answer

Oil pressure problem

there is no oil up in the intake area so its nothing you could have done BUT the oil pressure reading comes from the oil pressure sending unit near the dist. housing. you had to remove the dist. when changing the intake so maybe the sensor or it's connection are loose.
good luck chris
0helpful
2answers

1985 gmc sierra shakes

Nic, If the carburetor was dumping gas, remove the engine oil dip stick and see if it smells like gasoline. If it does you will need to change the oil.
Second, go back over your spark plug wires and verify they are on the correct spark plug. Start with the #1 plug wire, the firing order is 1,8,4.3.6.5.7.2...
Let me know how it turns out and we can go from there.
Good luck.
Not finding what you are looking for?

126 views

Ask a Question

Usually answered in minutes!

Top Cars & Trucks Experts

ZJ Limited
ZJ Limited

Level 3 Expert

17989 Answers

john h

Level 3 Expert

29494 Answers

Arnie Burke
Arnie Burke

Level 3 Expert

7339 Answers

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

Answer questions

Manuals & User Guides

Loading...