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  •  » Smell,Stink,Fumes,Eye Burning,Headache Casuing, IN your skin/clothes

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    6/04/2019 6:08 PM  #51

    M1Mustang69
    I FYI 24-7

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    Registered: 5/17/2013
    Posts: 477

    Re: Smell,Stink,Fumes,Eye Burning,Headache Casuing, IN your skin/clothes

    Thanks TKO....I can Assure you and anyone here Nothing but a 750 (or Higher) will be going on, the performance difference is that noticeable, I can assure you that....SO THE CURRENT UPDATE!!!:

    Buckle up this is a dousey:

    1. Used a camera to record the throttle plates and linkage position as to see what is happening at 1/3 throttle and obviously more...everything appeared just fine.
    2. Out of nowhere I did detect that my MIXTURE SCREWS now like to be SEATED???!!!  do not know why/how that happened.....So the usual suspect is a blown PV to which I was confident was not the problem.

    3. disassembled, cleaned with a air compressor and changed back to a 6.5hg.
    4.mixture screws want to be seated and idle roughens even at 2 turns out and thats just from 1!

    5. decided to just run the car on the Primary circuit with the notion that the BUCK was caused by the secondary circuit starting (which makes little sense given it only began after the first modification which was reducing both prim/sec. jetts) , so I disengaged the mechanical secondary and drove the car....much to my surprise the car RAN STRONG throughout all RPM range!!!! and  the BUCK vanished!!!!  completely.....
    --------So I then removed the secondary accelerator pump arm and BUCK remained Gone!

    *NOW i have extended cranking, rough idle during every start (which clears up) and the mixture screws like being seated....WTF Holley!?!?!?!?!?

    *should I remove the secondary PV completely and place a Plug?  should I further reduce the secondary jets given the car ran just fine (less power but still very impressively with just the primaries operating with 67's?)  also, when do the secondary Jets begin to throw fuel, my uneducated brain assumes always but logic would assume only once the plates begin to move???


    I think I maybe done entirely with Holley, this Mixture thing is complete nonsense
     

     

    6/04/2019 7:01 PM  #52

    TKOPerformance
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    From: Newark, DE
    Registered: 12/15/2014
    Posts: 7,084

    Re: Smell,Stink,Fumes,Eye Burning,Headache Casuing, IN your skin/clothes

    If its not responding to the idle mixture screws something is wrong.  With the screws seated its not getting fuel through that circuit, so its getting fuel somewhere else.  My first suspect would be the throttle blade angle being wrong and partially uncovering the transition slot.  That slot should be covered at idle, but sometimes guys crank the throttle blade to get a little more fuel at idle and make the engine more responsive to the screws.  That's a bad tuning solution.  A better one is to drill some small holes in the blades to increase the vacuum signal and pull more fuel directly from the idle passages.  I'd check for a partially uncovered transition slot before doing anything else. 

    I usually start tuning the idle mixture screws at 1.5 turns out from lightly seated.  That setting has literally allowed everything I've ever worked to to at least run and idle from a '18 Model T to an LS6 454. 

     

    6/04/2019 8:38 PM  #53

    HudginJ3
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    From: Cedar Hill, TX
    Registered: 4/29/2015
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    Re: Smell,Stink,Fumes,Eye Burning,Headache Casuing, IN your skin/clothes

    I have had a few issues with carbs and when I can't find the problem I have adjusted the carb so the engine will run as slow as possible by even adjusting the timing to make it do so. The advantage to that was that you could physically hear the vacuum where is was coming from. In the end TKO is right. I have even found that the throttle blades are not centered in the bore that causes the carb to not run correctly because the idle circuits are covered up.

    70, ragtop 351W/416 stroker Edel Performer heads w pro flow 4, Comp roller 35-421-8. T5
     

    6/04/2019 9:01 PM  #54

    MS
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    From: Canyon Lake, Texas
    Registered: 1/24/2013
    Posts: 11,729

    Re: Smell,Stink,Fumes,Eye Burning,Headache Casuing, IN your skin/clothes

    Man, this is why you never want to buy a swap meet carburetor!   No telling what has been done to them.

    Money you enjoy wasting is NOT wasted money... unless your wife finds out.
     

    6/04/2019 9:39 PM  #55

    M1Mustang69
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    Registered: 5/17/2013
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    Re: Smell,Stink,Fumes,Eye Burning,Headache Casuing, IN your skin/clothes

    Very True MS, but this came from a 30yr hot rod veteran who is a Guru....the carb was disassembled before storage and was unmolested; when I got it, it was thoroughly cleaned and no joke, first shot fired right up, idled and ran wonderfully (stench aside)......

    TKO nothing was done to the plates, again all this started with the changing of the jets (smaller).  the mixtures worked before, since the tweaking and fine tuning efforts they stopped functioning!?!?!?  Im Baffled.....

    my only guess at this point is the the jets may have come loose!?!?!  Question, is having the secondary curb idle all the way down (secondary plates closed) a bad idea?  and should I eliminate the secondary PV!? 

       •Thread Starter
     

    6/05/2019 3:18 AM  #56

    TKOPerformance
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    From: Newark, DE
    Registered: 12/15/2014
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    Re: Smell,Stink,Fumes,Eye Burning,Headache Casuing, IN your skin/clothes

    How's the float level?  Could it be siphoning fuel out of the vent?

    Again, its tough trying to do this over the web.  Hands on stuff is 3000% easier to diagnose.  I can't say what's causing your problem, but I can say that you 100% have a problem.  Its somehow getting fuel it shouldn't. 

    And, I'm done with used carbs.  I'll literally never buy another one.  20 years ago it was usually okay, worst case it might need a rebuild, but with what ethanol does to a carb if it sits in it too long forget it.  I had a Holley off a van I bought for the engine about 15 years back.  I figured it was a good way to recoupe some of what I paid for the van, so I grabbed a rebuild kit and figured I could get $150-$200 easy off an eBay sale.  That plan was great until I opened up the carb and discovered it was ruined.  The castings had been attacked to such a degree that there's no way it would ever have run right. 

     

    6/05/2019 2:31 PM  #57

    351MooseStang
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    From: Brookings, Oregon
    Registered: 4/03/2013
    Posts: 91

    Re: Smell,Stink,Fumes,Eye Burning,Headache Casuing, IN your skin/clothes

    TKO is right, if you can close the idle mix screws and it keeps running then it's getting gas from somewhere else. As he said, your transfer slots in the primary may be exposed because they are open too far.

    Are you running an auto or manual trans?

     

    6/05/2019 6:28 PM  #58

    RPM, aka Bearing Bob
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    From: Bakersfield, Ca
    Registered: 9/17/2013
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    Re: Smell,Stink,Fumes,Eye Burning,Headache Casuing, IN your skin/clothes

    Moose, he never replied that he adjusted them from this post a month ago,  so...

    rpm wrote:

    If your motor is idling with the idle mixture adjustment screw all the way in, I'm pretty sure you're getting your fuel because the fast idle speed screw (butterflies) are open too much. The carb needs to be removed for step one to be done, which is adjusting the butterflies.

     

    Bob. 69 Mach 1, 393W, SMOD Toploader, Armstrong  steering, factory AC.
     

    6/05/2019 7:59 PM  #59

    M1Mustang69
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    Re: Smell,Stink,Fumes,Eye Burning,Headache Casuing, IN your skin/clothes

    Thats Correct RPM....

    all this weirdness began after installing smaller jets on both....First the bucking - solution was to remove the Secondary Accel Pump Lever and now the mixture screws wanting to be seated.....The Car did begin to stall at idle once warmed up (stop signs/lights or harder braking), which is also New Phenomenon.  

    I then opened up the Curb Idle and it improved, yet the STENCH grew stronger.....Mixture screws still preferred to be seated (or nearly seated).
    So I increased the Idle on the primary and no more stalling, yet still mixtures like to be in.  Im going to try a 3rd PV, maybe that the culprit and Im going to ensure the jets are seated....
    I also lowered the float level with no success, PECULIAR stuff this is

       •Thread Starter
     

    6/06/2019 1:36 AM  #60

    351MooseStang
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    From: Brookings, Oregon
    Registered: 4/03/2013
    Posts: 91

    Re: Smell,Stink,Fumes,Eye Burning,Headache Casuing, IN your skin/clothes

    Thanks RPM!

    Right now it sounds like you have your primaries open too far to compensate for excessive fuel going into the engine. Have you looked down the primaries with a flashlight to look for fuel coming off of the venturis? I would get back to basics. Check fuel pressure, check float level, check the power valve for blowout, pull the carb and look at the transfer slots on the primaries, setting them so the slot looks like a square and then adjusting the secondaries to get the idle air right. If the mixture screws are closed, the engine is getting fuel from somewhere else. Another thing you can do if you have an electric fuel pump is that you can pull the carb and pressurize it to check for leaking.

    The reason I asked about the tranny is that if it's an automatic that you are running all I can say is good luck getting a double pumper to run on it. It can be done, I've done it, but it takes some knowledge of carbs and a hell of a lot of patience to get one dialed in. The automatic with a low stall converter and the vacuum secondary carb were made for each other.

     

    6/06/2019 11:18 PM  #61

    M1Mustang69
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    Re: Smell,Stink,Fumes,Eye Burning,Headache Casuing, IN your skin/clothes

    Its a Manual....T5 Super Duty.......

    Moose I was under the strong impression the procedure for initial setup was Secondary Curb Idle Transfer Slot was Little square, then you adjust Idle to its "happy place" with the Primary Idle Screw???

       •Thread Starter
     

     

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