Go Back   EcoModder Forum > EcoModding > EcoModding Central
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 11-07-2009, 05:51 PM   #1 (permalink)
EcoModding Lurker
 
Join Date: Oct 2009
Location: ethiopia
Posts: 30
Thanks: 16
Thanked 0 Times in 0 Posts
Thumbs up Normal carburettor fe settings

Dear Hyper milers
I decided to put up this post after cruising the net to find out sites that explain fuel air mixture settings on normal carbs and did not find a satisfying answer.According to an old russian automobile repair book there are two screws with springs on them[which is true]in newer vehicles there are more,what we are interested in are two screws one located at the accelerator cable end and the other at the base of the carb . The one located at the accel site is for idle speed control and the one at the base is for fuel air mixture control according to the book[very true].
So what we do is slightly tighten the idle screw to make it idle faster and then what we do is tighten the air/fuel mixture screw in finger tight with a flat screw driver,if u are right then u will notice the idle getting low,if engine is trying to stop or idle gets shaky,tighten the idle screw some more to achieve a stable idle speed.Now u should unscrew the air/fuel mixture screw a quarter turn and then try accelarting if it is good leave it and then try driving if there is a popping sound from carb it means fuel ratio is too low so unscrew the air/fuel screw a bit more and try driving again if there is no popping sound but u notice a jerky or sluggish behaviour unscrew the said screw a bit more.
Before doing all this it is a good idea to remove one spark plug and look at the color of the tip,if it is black and sooty then it means the above procedure must be done,An ideal spark plug color is gray,dark gray,reddish for certain fuel kinds.
Advantages of doing above procedure
1.fuel savings
2.engine oil lasts longer[less carbon fouling]
3.some older engines have a tendency to foul spark plugs when there is too much fuel entering the system.[of course this might also be from other factors].But I have helped many a poor soul who was told they need to get their engine overhauled to stop spark plug fouling.[of course most spark plug fouling is from a tired engine]
4.More power and sport car like speed[funnily the inverse applies,more air+less fuel =good performance.]
5.u become eco friendly less pollution
6.cat converter will not get clogged up.
7.less oil burning.
Disadvantages of doing above procedure
1.sluggish performance in the morning or cold weater.
2.longer warm up time.
3.carb is sensitive to smallest dirt particle in fuel.
4.jittery idle.
5.might need choke for morning starting.
The other point I wrote this point is because I noticed that most mechanics here usually adjusted carb idle speed by unscrewing the air/fuel screw a lot imagine the poor soul who is gonna drive that car.
jarre

any donations are welcome
GRACE KG AND PRIMARY SCHOOL
ACCT NUM:0130405841500
AWASH INT BANK GOFA
ADDIS ABABA ETHIOPIA

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 11-07-2009, 05:59 PM   #2 (permalink)
(:
 
Frank Lee's Avatar
 
Join Date: Jan 2008
Location: up north
Posts: 12,762

Blue - '93 Ford Tempo
Last 3: 27.29 mpg (US)

F150 - '94 Ford F150 XLT 4x4
90 day: 18.5 mpg (US)

Sport Coupe - '92 Ford Tempo GL
Last 3: 69.62 mpg (US)

ShWing! - '82 honda gold wing Interstate
90 day: 33.65 mpg (US)

Moon Unit - '98 Mercury Sable LX Wagon
90 day: 21.24 mpg (US)
Thanks: 1,585
Thanked 3,553 Times in 2,217 Posts
i'm going outside right now to adjust all the screws i can find. thanks and yes, there is another cheque in the mail!
__________________


  Reply With Quote
The Following User Says Thank You to Frank Lee For This Useful Post:
jarre (11-08-2009)
Old 11-07-2009, 06:44 PM   #3 (permalink)
Master EcoModder
 
Join Date: May 2009
Location: New Jersey
Posts: 389

2003 Ninja EX250 - '03 Kawasaki Ninja EX250
90 day: 78.57 mpg (US)

Saturn - '99 Saturn SL1 Base
90 day: 47.27 mpg (US)
Thanks: 25
Thanked 58 Times in 37 Posts
So basically you are leaning out the idle mixture screw a lot and compensating by raising the idle RPM adjustment.
__________________
Doing my part to reduce dependence on OIL
Doing my part to reduce congestion
And enjoying it!

If you have to use your brakes, you are driving too fast!

My 101.5 MPG 2003 Kawasaki Ninja 250




Crude Oil Price Today
  Reply With Quote
The Following User Says Thank You to theycallmeebryan For This Useful Post:
jarre (11-09-2009)
Old 11-07-2009, 07:43 PM   #4 (permalink)
Moderate your Moderation.
 
Join Date: Nov 2008
Location: Troy, Pa.
Posts: 8,919

Pasta - '96 Volkswagen Passat TDi
90 day: 45.22 mpg (US)
Thanks: 1,369
Thanked 430 Times in 353 Posts
Is this another one of those "How NOT to do something" threads?
__________________
"ʞɐǝɹɟ ɐ ǝɹ,noʎ uǝɥʍ 'ʇı ʇ,usı 'ʎlǝuol s,ʇı"

  Reply With Quote
The Following User Says Thank You to Christ For This Useful Post:
jarre (11-08-2009)
Old 11-08-2009, 01:03 PM   #5 (permalink)
EcoModding Lurker
 
Join Date: Oct 2009
Location: ethiopia
Posts: 30
Thanks: 16
Thanked 0 Times in 0 Posts
Smile thanx for reply and further updates

Dear hyper milers
I forgot to write that to test the screw setting what u can do is do a pre spark plug inspection and post spark plug inspection to see if the leaning out is working.Also closing off some of the more fancier vacuum lines that u deem unnecessary will help in performance.
Another test I use to check if the leaning out op was a success is first I clean the exhaust pipe outlet and look at what I have cleaned out before and after,if u did it correctly u will notice a noticable reduction in soot and water vapour or water droplets emerging and definite reduction in noxious smell.
Another thing I forgot to mention is that when a carb is wasting fuel the unburnt fuel enters the oil in the form of carbon and as fuel itself which in turn makes the oil dirty and the dangerous problem is it makes the engine oil thinner.I have had people complain of oil level increasing even thou there is no leak from the fuel pump to the engine.The thin oil easily enters the burn chamber and messes with the spark plug and u have more dangerous emmisions.
Another successful mod I tried on double carbs is I turned off the second carb[not for v8s because they have power needs] will send details
jarre


Last edited by jarre; 11-08-2009 at 01:17 PM.. Reason: update
  Reply With Quote
Reply  Post New Thread


Tags
air fuel ratio, carburetor, fuel economy

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Heat Pump Temp Lockout Settings to Gas Backup RH77 Saving@Home 3 03-11-2012 09:41 AM
iMovie Share Settings for 720p YouTube HD? SVOboy The Lounge 2 04-28-2009 11:57 AM
Redoing a Metro...how far away am I from normal MPG? PushnFords EcoModding Central 6 10-06-2008 12:35 AM



Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2023, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com