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    #31
    should be fine on the O-ring then. If its soft it will seal. After decades they get hard as a rock and will shatter if you poke at them. Same with the PCV valve grommet. I've actually stood on them without it deforming before, and I'm something of a fat ass.

    oil on the alternator bolt probably wicked there from a leaky valve cover gasket. Those go into a blind hole in the head. If the valve cover gaskets aren't the rubber ones, I'd change them while you have it open. Cork just don't last forever. Otherwise no need to open it. If the engine is nasty inside, you'll see it from inside the lifter galley when the lower intake comes off.

    Make sure the gasket surfaces are clean and flat. If there is pitting, a very very light wipe of RTV around the coolant passages will work. You want a dab in the 4 corners where the side gaskets meet the end wall gaskets. I use long bolts with the heads cut off as guide pins to hold the gaskets and align the intake on assembly. Pretty sure its a 5/16" bolt. If you get four that are 4" long and chop the heads off that'll do it.

    A few random suggestions. If you're removing the injectors from the lower intake, replace the O rings on them. If the caps are cracked you can get those too. Sometimes its sold as an "injector rebuild kit", but it will come with the cap and a pair of O rings. Might also not be a terrible idea to replace the fuel rail O rings either. You want the Viton seals. Not sure if the parts stores have them but its the same O rings Mustangs use, and I've bought them from Mustang places before. Usually they recycle OK but I have torn them in the past. I'd also give the upper and lower intake a good cleaning inside and out. The goo and sludge in there won't be doing you any performance favors. Don't get crazy trying to get it pristine but if you've got a big tote that you can mix up some degreaser in to let it soak, may as well. The Duplicolor Cast Coat Alumimum does a nice job of making things look like fresh raw cast aluminum too if you have any desire to pretty it up. The upper intake was painted a grey color but the lower was just raw aluminum.
    Last edited by gadget73; 05-23-2020, 10:45 AM.
    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
      If you have the awesome blue silicone intake end gaskets, use them.

      Distributor o-ring can be reused since it’s newer.

      I usually put a very thin layer of rtv around the coolant passages on the intake and the heads.
      1990 Country Squire - weekend cruiser, next project
      1988 Crown Vic LTD Wagon - waiting in the wings

      GMN Box Panther History
      Box Panther Horsepower and Torque Ratings
      Box Panther Production Numbers

      Comment


        #33
        I'll order some o-rings for the injectors and fuel rail. Might as well do everything while I'm in here. I did the PCV valve, screen, and grommet in January, which was a lot of fun with the intake in place. The grommet never fit very well though, so I'll put a little heat shrink tubing around it before reinstalling.

        Thankfully all 12 intake bolts came out without a hitch. Of the eight middle bolts, six were immaculate, while the two around the driver's side EGR passage were a little corroded. I assume the gasket failed and baked them in exhaust. The four corner bolts were all covered in sludge, which had me a little worried about what I'd find inside. But the lifter valley looks pretty good in my novice opinion. Most buildup looks like it's on the underside of the intake, and maybe on the pushrods - I don't know if that's a problem or not. A little coolant spilled into the valley as I removed the intake, but I'm hoping the engine will survive until I change the oil once it's all back together.

        The gaskets have definitely seen better days. I don't know if they're the originals, but they definitely look old. Whoever installed them seems to have put RTV around the coolant and EGR passages. The gaskets also cover up these four depressions on the heads between the middle and outer cylinders which seem to be designed to pool oil. I don't know how that much oil is getting in there or whether it's an intended feature, but I was a little surprised to find it.

        As for cleaning things up, I'm actually working on polishing the upper intake and EGR spacer. Not sure if I'll do the throttle body since the geometry is pretty tight. And the lower intake has some tricky spots too. But when they're done I was thinking of just putting a clear coat on to keep the aluminum from oxidizing. I don't know whether I need a heat tolerant paint or just whatever, as I don't think the intake should get too hot.
        Attached Files
        1987 Lincoln Town Car - Signature, "Prudence"

        Comment


          #34
          looks like this one had better oil change care than coolant system. Engine looks great, not so much on those coolant passages. I've been in engines that had big oil cookies that had to be broken up and vacuumed out before.

          standard paint should be OK. Just have to do something or it will turn into an oxidized mess again. The ones on my car are actually done in cast coat iron, makes for a nice dark grey. I did the manifold and valve cover on the diesel and actually had someone ask me where I got an NOS intake.
          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


            #35
            Well it's been a few months, but things are nearly back together. I've so far replaced the lower intake gasket, thermostat, and wire loom in the immediate area. Fuel injectors have all been rebuilt and everything north of the heads cleaned inside and out. I also threw some heat shrink tubing over the PCV valve grommet, which worked like a charm in making it seal properly. (And was 1000% easier to do with the intake out of the car.) The greatest time sink has been polishing the intake. If I'd realized how much effort it was going to be to sand everything down I probably wouldn't have gone down that path. But now I have a strong incentive to stick with the stock engine/power.

            Unfortunately, I haven't run the car now for any real length of time since February, and I'm worried the gas may have gone bad. I don't know whether it's worth trying to start the engine and see what happens, or if I'll save myself a lot of trouble by siphoning out the old fuel now.
            Attached Files
            1987 Lincoln Town Car - Signature, "Prudence"

            Comment


              #36
              Good idea on the heat shrink PCV. Intake looks good... one of those things I always liked but lacked motivation. February gas should be fine at this point.
              1990 Country Squire - weekend cruiser, next project
              1988 Crown Vic LTD Wagon - waiting in the wings

              GMN Box Panther History
              Box Panther Horsepower and Torque Ratings
              Box Panther Production Numbers

              Comment


                #37
                Dedication.
                ~David~

                My 1987 Crown Victoria Coupe: The Brown Blob
                My 2004 Mercedes Benz E320:The Benz

                Originally posted by ootdega
                My life is a long series of "nevermind" and "I guess not."

                Originally posted by DerekTheGreat
                But, that's just coming from me, this site's biggest pessimist. Best of luck

                Originally posted by gadget73
                my car starts and it has AC. Yours doesn't start and it has no AC. Seems obvious to me.




                Comment


                  #38
                  Originally posted by Lutrova View Post
                  ...Unfortunately, I haven't run the car now for any real length of time since February, and I'm worried the gas may have gone bad. I don't know whether it's worth trying to start the engine and see what happens, or if I'll save myself a lot of trouble by siphoning out the old fuel now.
                  I haven't run my Firebird in 3.5 years. It fired right up and has been running great on that old gas. I did fill the tank and put Sta-bil in it before I filled it and let it sit though.
                  1985 LTD Crown Victoria - SOLD
                  1988 Town Car Signature - Current Party Barge

                  Comment


                    #39
                    5 months isn't a problem. If it pings, top it up with some premium and just run it out.
                    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
                      I bolted the upper intake back on last night. Six bolts, two long ones in the middle, four short at the ends. But one of them was a stud. And I can't recall why it exists or where it's supposed to go. Is there a ground that I've forgotten about? (I replaced the eyelet connector for the ground at the back left of the lower intake.)
                      1987 Lincoln Town Car - Signature, "Prudence"

                      Comment


                        #41
                        Yes. drivers side rear. O2 harness ground.

                        for those with 86 model cars... another stud p.side for the heater tube.
                        ~David~

                        My 1987 Crown Victoria Coupe: The Brown Blob
                        My 2004 Mercedes Benz E320:The Benz

                        Originally posted by ootdega
                        My life is a long series of "nevermind" and "I guess not."

                        Originally posted by DerekTheGreat
                        But, that's just coming from me, this site's biggest pessimist. Best of luck

                        Originally posted by gadget73
                        my car starts and it has AC. Yours doesn't start and it has no AC. Seems obvious to me.




                        Comment


                          #42
                          the stud goes in the back corner. Some of them had a goofy U shaped bracket from the lower to the upper for reasons that I do not understand. It often got tossed, or sometimes it was just never 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


                            #43
                            Well, tomorrow's the big day. I thought I'd have everything together today, but I broke the spark plug wire connector to the coil so that it wouldn't snap on, so there'll be a parts run to Barstow before the moment of truth. I kind of miss the days (8 months ago) when I couldn't identify anything under the hood. It's a little nerve-racking thinking of the dozens of ways a 33 year old car can fail, especially now that I've had my hands on so many different parts.

                            In cleaning up some wires to the alternator I ran across a small wire that comes off the plug with the original charge wires and yellow (voltage?) wire, but instead of going to the alternator it snakes down along the underside of the engine. I followed it down to near the rear oil drain plug where it was dangling loose. The block in that area is pretty caked in dirt and oil, so it's hard to see where it might've originally gone. There's another wire that runs to some sensor just in front of the oil filter, so this isn't that. What did it go to and should I be worried about it?

                            Vacuum lines have all been replaced, or at least everything that isn't on the vacuum tree. I had thought most lines were in good shape, but as I replaced them I discovered just how brittle a lot of them were. One of the lines between the intake and EGR/smog pump may have already snapped - it's hard to tell whether that was from age or my handling as lines were replaced. Either way, it's all new now. And hopefully tracking down any vacuum leaks makes a difference, as I might have to register the car here in the PRC and pass emissions.

                            I did run the codes (only key on engine off) before calling it quits tonight. It gave me 31, 84, 10, and 15. 15 is a memory test failure, which makes sense since I've had the battery disconnected for the last three months. 10 doesn't appear to be a real code - not really sure what that means? 31 is 'EVP voltage below closed limit' - I don't know what EVP stands for or where I should be looking for this. And 84 is 'EGR Vacuum Regulator (EVR) circuit failure'. Is that the gizmo on the EGR valve, or one of the parts over on the passenger fender?

                            If the engine still doesn't run right, the one silver lining will be that it looks a lot cleaner. I was really surprised how well the intake shined up after I hit it with 1500 and then 2500 grit sandpaper. And I'm especially pleased with how sharp the cover plate turned out. As a project, polishing the manifold was a huge time sink and probably not worth the effort, but I guess now that it's done I'm happy about it.
                            Attached Files
                            1987 Lincoln Town Car - Signature, "Prudence"

                            Comment


                              #44
                              either the oil pressure sensor or the low oil level. Pressure sensor is right above the oil filter and has a push-on connector. Level sensor is in the rear part of the pan. Its supposed to unplug, but rarely does so people cut the wire to disconnect it. If your oil pan was replaced with one that doesn't have the sensor, thats why it doesn't go anywhere. Won't affect anything, you just won't have a working "check oil" light when it gets ~1 quart low.

                              10 is a spacer code. If this was key off, it appears between the active codes and the stored memory codes.

                              EVP is Egr Valve Position sensor. Its the plug on the back of the EGR valve. Low voltage usually means the sensor is bad, but could have a worn spot where the rod sits.

                              EVR is the thing on the fender that the EGR vacuum line connects to.
                              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


                                #45
                                Good news. At long last, the car has started and the engine's running smoothly. Or idling smoothly. I made my parts run yesterday and decided to bite the bullet and pick up new a new EGR Vacuum Regulator and EGR Valve Position Sensor. I swapped them in, ran another test, and both codes cleared out. So ultimately, I guess we don't really know which problem was causing the rough idle or the earlier surging idle. And I suppose it's possible the surging idle could come back, as that was an intermittent problem that I don't really know how to replicate. But between the MAP vacuum line being disconnected, the two EGR codes, and one or more other vacuum lines broken or disconnected, there were plenty of potential culprits.

                                The bad news is that I stripped out a bolt on the thermostat housing. Or I broke the bolt. I guess hopefully the latter, and maybe it's still in one piece. My problem really probably started when I bolted the thermostat housing back on without using any gasket maker, just relying on the gasket to do the job. Which it looks like it didn't, as I got a decent leak from there when I topped off the coolant. Trying to tighten the bolts to seal it up lead to my current problem. So now I know not to do that.

                                One more interesting development: When I finally ran the engine it idled high for a bit and then dropped, as I believe is normal. But within maybe 30 seconds I started hearing this noise like a belt squeal, but lower pitched and pretty loud. Best I can tell it was coming from the transmission - probably not a good sign. I haven't inspected the transmission closely, but there's definitely one, maybe two leaks. One puddle is about midway along the passenger side, and the other is at the back. The oil pan also has a fair number of drips around it. Some very light research earlier suggested I might need to change the output shaft seal. Is it possible this seal could also cause a squeal? Or do I have bigger problems?
                                1987 Lincoln Town Car - Signature, "Prudence"

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