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Thread: E4ME...2 Questions

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    Member HammerDown's Avatar
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    Default E4ME...2 Questions

    Hi people...if some recall I was having all kinds of idle issues well...I finally purchased and installed a rebuild kit from Cliff's Performance Q-Jet Carburetors.
    It's on the car and running better however...
    Two questions about these two adjustments below V
    1)Lean mixture solenoid adjustment screw (the tiny funky screw)
    2)Idle air bleed valve adjustment - larger flat head (set with dwell meter)

    #1. I have that tiny solenoid screw two turns out from seated (where it was originally) > should I mess with it while it's running (or) is there a starting point how many turns out from fully seated it should be??? And no, the gauge did NOT come in Cliff's rebuild kit

    #2. I know a dwell meter is needed for the Idle Air Bleed Valve Adjustment (which I have but) > what should the meter be set on (dwell, volts, rpm?) and the meter has two wires one GREEN one BLACK...which wire goes to that green-clippy thing hanging near the carb and does the black meter wire go to ground?
    Also > at the "dwell reading" do I focus on the 6 or 8 cylinder side???
    And, what 'number' am I looking for while turning the idle air bleed adjustment?


    PS my carb was very clean inside, I hoped to see some blocked passages, air bleeds etc but saw nothing...HOWEVER...I do believe the main problem was the two idle air bleed valve o-rings were bad.
    Oh, and Cliff suggested minimum 5-turns out on the two lower air/idle/mixture screws...so that's where they're set at.

    Much thanks for any feedback, Ray

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    Hello Ray,

    Always nice to see somebody that is brave enough to rebuild a E4ME
    To set the lean, rich and idle air bleed you need special tools from Thexton (Thexton 362 and Thexton 370)
    To set the idle air bleed just right, connect the green lead to the green connector near the carb, your black dwell connector to ground (I put it on the exhaust air system), put it on DWELL 6cyl. And turn the air bleed very slowly at 1/8 turn max to get 30 degrees. Remember to let the carb idle for a time before adjusting it again, it takes a minute or so for the carb to correct to the new idle air bleed position

    Cliff, is right, I turned the mixture needles about 6 turns out even after reclasing the mixture needle holes. But start from there and you'll be fine if the engine is about stock.

    Greetings Peter
    HammerDown likes this.

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    Quote Originally Posted by Peer81 View Post
    Hello Ray,

    Always nice to see somebody that is brave enough to rebuild a E4ME
    To set the lean, rich and idle air bleed you need special tools from Thexton (Thexton 362 and Thexton 370)
    To set the idle air bleed just right, connect the green lead to the green connector near the carb, your black dwell connector to ground (I put it on the exhaust air system), put it on DWELL 6cyl. And turn the air bleed very slowly at 1/8 turn max to get 30 degrees. Remember to let the carb idle for a time before adjusting it again, it takes a minute or so for the carb to correct to the new idle air bleed position

    Cliff, is right, I turned the mixture needles about 6 turns out even after reclasing the mixture needle holes. But start from there and you'll be fine if the engine is about stock.

    Greetings Peter
    Hi Peter, I was hoping you would respond...no special tool needed for the "Lean mixture solenoid adjustment screw" (the tiny funky head screw) as when I had the carb apart I simply put a slot in it so a small screwdriver works just fine
    I did find out the funky screw needs to be 3.50 turns out from lightly seated.

    And now that you clarified the dwell connections and related info I do that adjustment tomorrow.

    Not sure why I was apprehensive about getting into the E4ME as it wasn't scary at all, and glad I didn't ship it to someone for the rebuild.
    The engine is idling very good now but I want to tweak that 'idle-air-bleed-adjustment' and I need to play with the electric choke a bit as dead cold start-up is a tad rough until heat builds.

    Thanks again, Ray

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    Member HammerDown's Avatar
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    Done deal...Dwell is hovering at 30 +- 2 and good enough for me > (1.25) turns out from fully seated)
    I can tell the carb is very close as when I give it a 'slight' whiff of starting-fluid the engine pretty much does nothing, where as before the carb rebuild the engine would rev-up hard cause it was very lean.
    I may go out to 6 turns on the two lower idle mixture screws (maybe)

    Considering deleting the air-pump and related components...no emissions check for me as I'm well under 5,000 miles a year.

    PS readjusted the electric choke and looks like the dead cold start problem is solved too.

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    Member HammerDown's Avatar
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    UPDATE...engine is running better than I can ever remember

    Kinda has me wondering...what's next

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    No problem, and good to read your engine is running much better!
    As for the idea behind the mixture solenoid, if you understand this the carb will be much better to understand.
    The primairy rods have two positions, high (lean condition) and low (rich condition). The rods are hanging in the jets on springs. So you can say the position of the rod in the jet is "known" (as the rod has a stepped thickness). But now the solenoid that is controlling the rod doesn't have a known position, so you need to "measure" and set the solenoid lean position relative to the jet. Now when the solenoid is active and the rod is down in the jet its at a known position for the ECM. Next you set the rich stop, then you measure the distance between the lean and the rich position (total rod travel). Same story base setting for the ECM. For example if the lean positioning is 20% below perfect (14.7) air/fuel ratio and the rich position is 20% above AF ratio on average the ECM will energize the solenoid 1/2 the time to come to the 14.7 AF ratio, giving you the 30 degrees dwell. Other example. If you set the lean stop 10% below 14.7 and rich 30% above 14.7 when the engine is running the on average the carb will give a rich condition (because the rod has more room to travel to the rich side then to the lean side). So the ECM will energize the solenoid more to hold the rod down longer in the lean postion, as a result the dwell meter will show a "rich" condition. And maybe with the 10/30 setup the ECM is still capable to reach the 14.7 ratio, but the carb doesn't have much room on the lean side to correct a rich condition as it has on the rich side to correct a lean condition. With the dwell meter you don't correct a inbalance between the rich and lean stops but you correct the idle mixture (fuel delivery) to correct the problem on that end (for the example lean the mixture out). I hope you understant is a little, I don't know if I do

    Greetings Peter

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    Thanks for the explanation Peter...and very well said.
    Once I got into the carb I had a better idea of hoe the thing works. I'll still be a "Holley" man till the end.
    Engine is running amazingly good > almost too good to be true.

    Again, thanks to the good people here for all the support and guidance >

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    Here's a question...are you setting the 30 degrees dwell with the air clear lid on or off?
    As I just checked it and there is a 10 degree difference with it on > goes to 40 degrees.
    I just reset it with the cover on for 30.

    UPDATE > around town, idle and off-idle engine runs even better!

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    There should be a little difference between the air lid on of off but not 10 degrees.
    I don't know if 40 is lean or rich but if it's on the rich side check the following:

    There is a temp switch inside the air lid. A vacuum line is connected to it which connects to the two "flaps" inside the nozzles. So first the switch needs to be warmed up so the flaps will open and let air in. Check if the vacuum lines are connected the right way and if the flaps open when the air lid is warm.

    Greetings Peter

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    Update...carb was rebuilt (by me) engine was idling/running smooth then for whatever reason (today) it's back to a rough idle again.

    Coming down from upper RPM it will hover a 700rpm, then drop to maybe 500rpm and be rough and miss.

    Also, nasty strong exhaust smell, 'not' like gas from loading-up.

    BTW, at idle I'm not hearing the usual clicking from the carb.

    Thoughts??????????

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    I had the same thing but only cruising back from a WOT sprint. It would load up and I could see the A/F ratio meter getting richer and richer (from a normal 12:1 under acc to 6:1 were it almost stalled) I think it would only get better when shutting down the engine and restart. As I destroyed the carb during a rebuild (trying to find the problem) I can't tell you what the problem is.

    If you can't here the solenoid try hooking up the dwell meter to see what it is doing and if it's working. It would be logical that if the solenoid stopped working that the rod's are stuck in the full rich position which is in line with the problem.

    Greetings Peter

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    If the idle changed overnight, I look for a vacuum leak. Did any of the vacuum hoses get knocked off? The e4me runs so nice when everything is right, but it needs everything to be right, especially vacuum. Just my thoughts, check the easy stuff first

    You mention that it was rebuilt again by you? Did you open it up again, what made you do that?

    The lean and rich stop adjustments. If the ECM is not throwing a lean or rich code, than it is having no problem keeping the mixture within the parameters of the ECM. Leave the adjustments alone, changing them will change the " dwell" but the overall a/f mixture should be the same. I hope that makes sense. If the ECM is throwing a lean code, you can raise the rich stop screw, but that is most likely a vacuum leak also

    good luck

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    Quote Originally Posted by Wajulia View Post
    If the idle changed overnight, I look for a vacuum leak. Did any of the vacuum hoses get knocked off? The e4me runs so nice when everything is right, but it needs everything to be right, especially vacuum. Just my thoughts, check the easy stuff first

    You mention that it was rebuilt again by you? Did you open it up again, what made you do that?

    The lean and rich stop adjustments. If the ECM is not throwing a lean or rich code, than it is having no problem keeping the mixture within the parameters of the ECM. Leave the adjustments alone, changing them will change the " dwell" but the overall a/f mixture should be the same. I hope that makes sense. If the ECM is throwing a lean code, you can raise the rich stop screw, but that is most likely a vacuum leak also

    good luck
    Question > what are you calling the "rich stop screw" ???
    One of the below ???
    1)Lean mixture solenoid adjustment screw (the tiny funky screw)
    2)Idle air bleed valve adjustment - larger flat head (set with dwell meter)

    8/2011 I removed the carb and FULLY rebuilt it with a kit from 'Cliff's High Performance". It had some gas weeping from here and there. The o-rings on the Idle Air bleed valve were bad, I believe that was it's main problem. To my surprise the carb was spotless clean inside.

    Engine was running good, then the other day I came to a RED light and bam, idle dropped to 500rpm and was rough. Anything above idle is better.

    I'm thinking a vacuum leak too, but where do I even begin, and how to find it ???

    One item part that has given me vacuum leaks is that rubber cone in the headlight door actuator.

    'Peter"...guessing once the Dwell meter is hooked-up and 'if' the meter doesn't show a reading the "solenoid" is dead > correct?

    I'll have time to look it over today, at least it'll be 45 degrees outside
    Last edited by HammerDown; 01-07-13 at 09:05 AM.

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    You can disconnect the M/C connector is there is no change in the sloppy idle then the solenoid isn't working. I have to say I disagree with Wajulia (sorry forgot your name) when my engine is almost stalling from to much fuel only then I get a rich code but by then its getting 2x the fuel it needs.

    There are 3 screws. You found the first two but the third one is also there. On top of the "tower" is the idle air bleed valve. Still in the tower but in front of the idle air bleed valve is the lean mixture screw. This screw moves the entire solenoid up and down (in reference) to the Jet (you need to measure it when the carb is open).
    Then you have the rich stop that is located in front of the tower. You have a little upstanding cilinder (maybe the plug is still in it) below the plug is a screw the the rich plug attached to it. There could be a fixed distance the mixture rod is traveling between the lean and rich mixture stop.

    Easy way to check the vacuum hoses is plugging them at the carb. Then you check all the hoses at ones.

    Greetings Peter

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    Update...
    The battery was disconnected for two days, hooked it up, started and it idled good again.
    I hear the ECM clicking.
    I remember a loooong time ago my mechanic told me to disconnect the battery to reset the computer.
    Do you think it may have had a little computer-hiccup and resetting it cured the issue?

    While idling, for a few seconds I disconnected the TPS, it idled even better
    While idling, for a few seconds I disconnected the ECM connector, dwell meter went to zero, can't say it idled worse
    Re-hooked both the above and went for another 'idle air bleed' adjustment @ 30 degrees

    I did locate the "rich stop screw" > plug is out however I don't have the appropriate tool to adjust it.

    I didn't get to test drive; to see if it would act-up again, as I'm not feeling very well

    I'll be able to test-drive tomorrow.

    Your feedback is ALWAYS greatly appreciated
    Last edited by HammerDown; 01-07-13 at 03:21 PM.

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