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    #31
    There should be a screw on the side where the high idle cam is that sets it. Its on the side opposite the dashpot, sort of tucked in there behind the hockey puck. Shine a flashlight in there and you should be able to find it.
    86 Lincoln Town Car (Galactica).
    5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

    91 Lincoln Mark VII LSC grandpa spec white and cranberry

    1984 Lincoln Continental TurboDiesel - rolls coal

    Originally posted by phayzer5
    I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

    Comment


      #32
      Originally posted by gadget73 View Post
      There should be a screw on the side where the high idle cam is that sets it. Its on the side opposite the dashpot, sort of tucked in there behind the hockey puck. Shine a flashlight in there and you should be able to find it.
      Got it! Tried fiddling with it, but set everything back to where I started as some new questions arose. How do I know for certain that the fast idle cam index is set? I can't see the cam from any vantage point and I think with the choke valve closed the idle screw is supposed to be at the 'v' step on the cam. From there I'm supposed to set it to 1550 rpm (or as near as my ear can tell as I have not tach). Here's what I think I'm supposed to do:

      1. Get the car running to temp.
      2. Remove and plug the vacuum hose to the EGR.
      3. Close the choke plate to set the screw onto the fast idle step of the cam.
      4. Adjust the screw until she's purring at 1550 (ish).
      5. Unplug the vacuum hose and put it back on the EGR.
      6. I'm done.

      Please feel free to correct me or adjust my procedure here.
      ************************************************** ******************************
      1997 Crown Vic - Mostly rust free, moderate mileage. On the road... but far from perfect. **SOLD**
      1985 Crown Vic in 2-Tone Blue **SOLD**
      http://automophiliac.blogspot.ca/

      Comment


        #33
        I've never owned a car with this particular carb, so I don't know if thats exactly it. It sounds about right, but there may be some specific detail I'm unaware of. Most of my time with carbs has been on Chevy smallblocks with Q-jets and VW Beetles with either the stock 1bbl or a pair of Weber carbs that had no choke or high idle stuff. from someone who daily drove that in the winter for a couple years, chokes are a mighty nice thing to have.

        The cam is what the screw sits against. If you can see the screw, usually you can see the thing that it contacts. It may only be visible when the choke is shut though, not sure how clear your sight lines are in there.
        86 Lincoln Town Car (Galactica).
        5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

        91 Lincoln Mark VII LSC grandpa spec white and cranberry

        1984 Lincoln Continental TurboDiesel - rolls coal

        Originally posted by phayzer5
        I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

        Comment


          #34
          Well it's a little confusing in terms of the procedure... I think it's on a label on my fan shroud. All things being equal, it's probably in my best interest to follow those instructions.

          The vision issue is because the step down cam is directly behind the choke spring housing... i.e. obstructed as hell. So I can't even see if it's on the right setting or not. I'll grab a step stool and see if I can get an areal view.

          All in all it isn't so bad. The choke opens perfectly once it's hot, so that part is working. It's just the fast idle and the step down is a little mucked up and since I can't see it's been a little frustrating. But I'll get it... rest assured!

          As a side note... I think the choke plate just closed when cold (i.e. i don't have to push the gas pedal to close it... it's just it's natural cold state)... I'm not sure what's happened there. I'm going to check it out right now.
          ************************************************** ******************************
          1997 Crown Vic - Mostly rust free, moderate mileage. On the road... but far from perfect. **SOLD**
          1985 Crown Vic in 2-Tone Blue **SOLD**
          http://automophiliac.blogspot.ca/

          Comment


            #35
            the way the linkages work, you have to push the gas pedal down to drop the high idle cam in. The choke can close most of the way without it, but the high idle won't set, which will tend to hold the choke somewhat open.
            86 Lincoln Town Car (Galactica).
            5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

            91 Lincoln Mark VII LSC grandpa spec white and cranberry

            1984 Lincoln Continental TurboDiesel - rolls coal

            Originally posted by phayzer5
            I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

            Comment


              #36
              Originally posted by gadget73 View Post
              the way the linkages work, you have to push the gas pedal down to drop the high idle cam in. The choke can close most of the way without it, but the high idle won't set, which will tend to hold the choke somewhat open.
              Makes sense.

              I was reading the instructions though on my fan shroud and it says you should have the car at normal operating temp. How do you set the cam with the car running? Hit the gas, hold the plate closed to keep it in place and then let the gas go?

              Subsequently, my efforts were not that successful tonight... most likely due to what you are mentioning. Now all my adjustments are out of wack and the car she no run so good. I think though that may have to do with the idle mixture. My idle is running high, but I think my screws are in too deep so it's running a but crappy. Damn screws are hard to access though while the carb is on the car. Bugger.

              Just so everyone knows, the instructions I followed suggested 1.5 turns out... but now I'm reading lots of places are saying 2.5 turns out.

              Anyway, mega discouraged at this point so I'm taking a little break.
              ************************************************** ******************************
              1997 Crown Vic - Mostly rust free, moderate mileage. On the road... but far from perfect. **SOLD**
              1985 Crown Vic in 2-Tone Blue **SOLD**
              http://automophiliac.blogspot.ca/

              Comment


                #37
                you can probably push on a linkage to drop the cam in. Without seeing it I don't know specifically but if you can find it and see what it hooks to, its usually not that hard to figure out what to push or pull in order to force it to drop in. Most of the time its just a rod going somewhere that you'd have to operate by hand instead of letting whatever controls it normally handle the task.


                Idle mix screws are usually set somewhere to start, then you fine tune them per-vehicle. The way I always did it was to set the idle RPM where you want it, and hook up a vacuum gauge. Adjust for highest vacuum, re-adjusting the idle speed screw as needed to keep the rpm right. Move the two screws equally, usually no more than 1/4 turn at a time. Wherever you find the setting that has highest vacuum at the desired rpm is generally correct. Some carbs will want you to tweak the screw in or out a small amount from that point though. I don't know the Motorshaft 2100/2150 well enough to know if its one of those. Most of the time you won't need to move the screws very far from the initial setting.

                Also, just as a mention, but the timing must be correct in order for this to work really properly. The engine also must be warm, and the choke must be fully open.
                86 Lincoln Town Car (Galactica).
                5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                91 Lincoln Mark VII LSC grandpa spec white and cranberry

                1984 Lincoln Continental TurboDiesel - rolls coal

                Originally posted by phayzer5
                I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                Comment


                  #38
                  I discovered that when I take the heat shield off the front of the Choke assembly, I can see everything a lot easier and actually access the fast idle cam. I also found a diagram of the whole works on AutoZone (thanks for the link!) which was pretty helpful.

                  Instructions for the idle mixture are max vacuum at desired rpm... from what I've seen anyway. I'm going for smooth sounding as I don't have access to a vacuum gauge (I'll double check everything on Sunday at my in-laws... they have EVERYTHING in terms of tools and diagnostic equipment. If you don't already, get to know some farmers).

                  Also, I've been doing all my adjustments on a warm motor... it's what my fan shroud told me to do and, dammit, who am I to argue?
                  ************************************************** ******************************
                  1997 Crown Vic - Mostly rust free, moderate mileage. On the road... but far from perfect. **SOLD**
                  1985 Crown Vic in 2-Tone Blue **SOLD**
                  http://automophiliac.blogspot.ca/

                  Comment


                    #39
                    yeah, you can't tune a cold motor. Also, you don't have a cold motor for all that long, so it would be useless to spend huge amounts of time futzing with it. Makes more sense to do it fully warmed up since its pretty constant once the thermostat opens.


                    Spend some time at flea markets. A tach and a vacuum gauge should be cheap to obtain. You often see old mechanics tools for nearly nothing. Nobody knows what a dwell-tach is anymore. The dwell isn't useful unless you have points, but tachs are tachs. A vacuum gauge is a surprisingly useful diagnostic tool too, especially for how simple and cheap they are.
                    86 Lincoln Town Car (Galactica).
                    5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                    91 Lincoln Mark VII LSC grandpa spec white and cranberry

                    1984 Lincoln Continental TurboDiesel - rolls coal

                    Originally posted by phayzer5
                    I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                    Comment


                      #40
                      Originally posted by gadget73 View Post
                      yeah, you can't tune a cold motor. Also, you don't have a cold motor for all that long, so it would be useless to spend huge amounts of time futzing with it. Makes more sense to do it fully warmed up since its pretty constant once the thermostat opens.


                      Spend some time at flea markets. A tach and a vacuum gauge should be cheap to obtain. You often see old mechanics tools for nearly nothing. Nobody knows what a dwell-tach is anymore. The dwell isn't useful unless you have points, but tachs are tachs. A vacuum gauge is a surprisingly useful diagnostic tool too, especially for how simple and cheap they are.
                      Well, I think I finally have it running right in terms of warm operation, idle mixture and curb idle. Still don't think my fast idle is working too right, but it doesn't seem to be hampering operation at all. Choke shuts when I press the gas, opens as it warms up. In fact she's driving really smooth, shifting nicely, etc. The only thing really throwing me off is the crappy condition of my exhaust. That's next year's chore though.

                      I am going to try to get to the bottom of the fast idle on Sunday. I think it's just an idle cam indexing issue. Friend of the family is a retired mechanic and he offered to go over it with me. We'll have access to all the diagnostic stuff we could possibly need.
                      ************************************************** ******************************
                      1997 Crown Vic - Mostly rust free, moderate mileage. On the road... but far from perfect. **SOLD**
                      1985 Crown Vic in 2-Tone Blue **SOLD**
                      http://automophiliac.blogspot.ca/

                      Comment


                        #41
                        Just to follow up and close this issue... and I think I wrote about this on my Readers' Rides Thread.... the problem was the choke pull-off wasn't pulling off enough. I noticed this when I took the carb off again to replace the mounting gasket that came with my kit (that one was too thin and I had a gas boiling issue) and to replace a leaky egr plate gasket.

                        What was actually happening was that they fast idle screw that sits on the idle cam was never coming off of fast idle. So that's what I was running around on all the time! Silly me.

                        In the end all it took was a few turns of the screw at the back of the pull-off and my problem was solved. It's always the small details!
                        ************************************************** ******************************
                        1997 Crown Vic - Mostly rust free, moderate mileage. On the road... but far from perfect. **SOLD**
                        1985 Crown Vic in 2-Tone Blue **SOLD**
                        http://automophiliac.blogspot.ca/

                        Comment

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