81 quadrajet
Thread Starter
Racer
Joined: Oct 2007
Posts: 431
Likes: 22
From: Chester Illinois
81 quadrajet
some days my 81 runs great and then other days it wont idle. i have messed with it so much i am about to give up. seems like when i un hook most the vacuum lines and plug them at the carb it idles the best. my question is which lines are not necessary for this computer driven carb to work??????? the smog pump has been removed. and buy the way, who is Lars??????? thanks namvet
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
Lars Grimsrud is probably the foremost expert on Quadrajets in the world.
He used to be a member here on the forum, but got tired of arguing with people who did not know what they were talking about yet insisted they knew better than him. He is a great guy that is still available to help anyone who needs his help. I've never met anyone quite like him, he genuinely just seems to like to help people out with their cars with no ulterior motive. He does not, however, deal with E4MEs specifically, like our '81s, so you are stuck with us wannabes!
God bless, Sensei
He used to be a member here on the forum, but got tired of arguing with people who did not know what they were talking about yet insisted they knew better than him. He is a great guy that is still available to help anyone who needs his help. I've never met anyone quite like him, he genuinely just seems to like to help people out with their cars with no ulterior motive. He does not, however, deal with E4MEs specifically, like our '81s, so you are stuck with us wannabes!
God bless, Sensei
Last edited by a1sensei; Apr 1, 2009 at 10:11 PM.
Thread Starter
Racer
Joined: Oct 2007
Posts: 431
Likes: 22
From: Chester Illinois
thanks for the info. just had a new egr valve installed. did seem to help. this usually happens after you kick the secondaries in and then come to an idle. it will idle real rough and then sometimes it will idle perfect. one time i was setting the idle up so it would idle even though it was idling rough. all of a sudden it just smoothed out and then it was idling too fast so i had to set the idle back down. might run perfect for a time and then it happens again. could the computer be acting up??????? thanks again namvet
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
Here are some things that could be causing your problems:
Damaged/Leaking Needle/Seat: These are easily damaged and should be replaced any time carb has flooding or fuel control problems.
Fuel-Logged Float: Old floats will absorb fuel and start sinking. Replace it with a new nitrophyl float..
Jammed M/C solenoid: Check by inserting a long thin allen wrench down a “D” vent in the choke tower and be sure the solenoid moves down and springs back up freely.
Emulsion tubes fallen out of air horn and laying in float bowl
Loose throttle plate
Clogged air bleeds
Leaking well plugs or porous casting: This is not likely in an E4ME
Warped air horn or secondary throttles not closing: I doubt this is it unless someone incompetent has worked your carb, or it has suffered severe trauma.
God bless, Sensei
Damaged/Leaking Needle/Seat: These are easily damaged and should be replaced any time carb has flooding or fuel control problems.
Fuel-Logged Float: Old floats will absorb fuel and start sinking. Replace it with a new nitrophyl float..
Jammed M/C solenoid: Check by inserting a long thin allen wrench down a “D” vent in the choke tower and be sure the solenoid moves down and springs back up freely.
Emulsion tubes fallen out of air horn and laying in float bowl
Loose throttle plate
Clogged air bleeds
Leaking well plugs or porous casting: This is not likely in an E4ME
Warped air horn or secondary throttles not closing: I doubt this is it unless someone incompetent has worked your carb, or it has suffered severe trauma.
God bless, Sensei
Burning Brakes
Joined: Dec 2007
Posts: 952
Likes: 0
The E4ME has the same problems here as the earlier units. They are virtually identical.
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Thread Starter
Racer
Joined: Oct 2007
Posts: 431
Likes: 22
From: Chester Illinois
thanks for the advice a1sensei. just had the carb rebuilt by a dealer that had an older guy that used to work on these in the old days. new float, new choke pull-off and new egr valve. started it this evening and it ran and idled good. who knows when it will happen again. am running the timing between 12 and 14 btdc. now my next project is the left power window regulator. have it out and the gear is stripped. any body got a schematic how this all goes back together. my shop manual doesnt go into much detail. thanks namvet
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
God bless, Sensei
Drifting
Joined: Apr 2006
Posts: 1,911
Likes: 2
From: gold coast queensland
glad you got your carb fixed. i have an 81 too and unless you deal with them all the time like sensei and lars etc etc i wouldnt mess with them. i was going to mention the bump up solenoid for aircon may be bad as well...but doesnt matter now, hopefully it keeps running well for some time.
for your stripped teeth i would certainly recommend this repair kit over totally replacing the tooth gear. its relatively quick once you have the window actuator out of the door and works perfect. mine has been in for 2 years and no problems. there is a post in here with alot of help when i bought mine about tricks when re-installing. such as using bolts/nuts instead of rivets when you put it all back in. if you cant find it let me know and ill give you a link.
for your stripped teeth i would certainly recommend this repair kit over totally replacing the tooth gear. its relatively quick once you have the window actuator out of the door and works perfect. mine has been in for 2 years and no problems. there is a post in here with alot of help when i bought mine about tricks when re-installing. such as using bolts/nuts instead of rivets when you put it all back in. if you cant find it let me know and ill give you a link.
Thread Starter
Racer
Joined: Oct 2007
Posts: 431
Likes: 22
From: Chester Illinois
thanks gingerbreadman. i was thinking about what you have suggested. the gear on the motor looks pretty good. i do need some other rollers and stuff. do they make a kit for this??? i would like to read the link that you are talking about for i have parts laying everywhere. on the carb fix, i wouldnt say it is fixed. havent driven it enough to really find out. been raining almost every other day. thanks again, namvet
